Meteorological Society of New Zealand Newsletter 161 Winter 2020 Page 1
ISSN 0111-1736 (Print) ISSN 2624-4640 (Online)
Meteorological Society Of New Zealand (Inc.)
NEWSLETTER 161 Winter-2020
See our website for the pdf
Meteorological Society of New Zealand Newsletter 161 Winter 2020 Page 2
Meteorological Society Of New Zealand (Inc.)
NEWSLETTER 161 Winter 2020
PO Box 6523, Marion Square, Wellington 6141, New Zealand
Please forward contributions to Bob McDavitt,
CONTENTS Page
Foreword from our President 3
Conference 4
Around the Regions 5
Autumn: NIWA review this time 5-6
Notable events 6-9
Christchurch 10
Pick of the clips 11-34
Your Committee for 2020
President: Michael Martens Immediate Past President: Sylvia Nichol Secretary: Katrina Richards Treasurer: Gregor Macara Circulation Manager: Lisa Murray Website Liaison: Tim Gunn (new) Journal Editor: Nava Fedaeff Newsletter Editor: Bob McDavitt Auckland VP: Petra Pearce Wellington VP: [vacant– President is from Wellington] Christchurch VP: Jiawei Zhang Dunedin VP: Daniel Kingston General Committee: Luke Sutherland-Stacey, Silvia Martino(new), & James Renwick (new) Student/early carrer scientist: Ethan Dale (new) Views and endorsements expressed in this newsletter are those of the
contributors and advertisers, and not necessarily those of the
Meteorological Society of New Zealand.
The mention of specific companies or products does not imply that they
are endorsed or recommended by the Society.
Meteorological Society of New Zealand Newsletter 161 Winter 2020 Page 3
Tēnā koutou members and whanau
We are halfway through 2020 already. The days have gotten short and we are in the middle of winter. The weather certainly does fell more and more like it. The Covid-19 pandemic has of course also affected the MetSociety and the work of the committee. It delayed the planning for our annual conference and made some of the work of the committee more difficult. However, in other ways it has also made collaboration between committee members easier, through the increased use of online platforms and the use of online meeting software. This has improved our productivity in some ways, with committee members being based around the country.
I can assure you that the MetSociety committee will continue to work un-interrupted and we will continue to support our scientific community and members. Our membership numbers are stable, and our financial situation is robust and healthy, so that we can buffer loss of income should this eventuate during this or the next financial year.
I’m also very pleased to announce that our annual conference will go
ahead this year and will take place 23.11.20 – 27.11.20 at the University of Canterbury. We are trying a few new things and are expanding the conference. This year, we will have special student-focused sessions on Monday and Tues-day, special aerosol/air pollution sessions on Tuesday and the main conference Wednesday, Thursday and Friday. I’m very glad that we were able to secure a joint conference with the aerosol and air pollution research group and were able to secure a great venue at the University of Canterbury. The deadline for abstract submissions for the conference will be 10.08.2020. If you would like further information, please go to our dedicated conference webpage: https://www.metsoc.org.nz/metsoc-conference/.
Especially during these uncertain times, the MetSociety will continue to be your go to place for reliable and up-to-date earth system science news and community engagement. We will continue to support you and be available for our members and the science community in general and we are looking for-ward to welcoming you all to our annual conference in Christchurch at the end of November this year. Kia Kaha, Ngā mihi nui,
Michael Martens President of the Meteorological Society of New Zealand
Meteorological Society of New Zealand Newsletter 161 Winter 2020 Page 4
Second Circular and Call for Abstracts
We are pleased to announce that the Meteorological Society of New Zealand’s annual con-
ference will be held at the University of Canterbury, Christchurch, from Wednesday 25th to
Friday 27th of November.* This year, the conference will include special sessions dedicated
to aerosol and air pollution research, and student-focused sessions/seminars. Student ses-
sions will take place on Monday 23rd November and Tuesday 24th November, and aerosol/
air pollution sessions on Tuesday 24th November; further details will follow.
The Society invites contributions on any topic associated with meteorology and climate.
These include (but are not limited to): the large-scale circulation of the atmosphere and
oceans; ocean-atmosphere interactions and physical oceanography; remote sensing; at-
mospheric chemistry; urban meteorology; aerosol and air pollution; agricultural and bio-
meteorology; hydrological applications; weather and climate hazards and impacts, includ-
ing global change; and the history of New Zealand meteorology and oceanography.
There will be three presentation options:
Poster presentations, with one-minute introduction.
Standard oral presentations of 20 minutes’ duration, including Q&A.
Short, Pecha-Kucha type oral presentations (5-6 minutes).
The number of standard oral presentations will be limited. In addition, we will have invit-
ed speakers giving keynote presentations each day.
Please complete the Google Form to express your interest (for attendance and presenta-
tions) and to submit your abstract by August 10th 2020. Please direct any questions about
the conference to Jiawei Zhang ([email protected]) or Silvia Martino
([email protected]). The registration fee for the conference will be an-
nounced in August. Details about the conference programme, including the conference
dinner and the Society’s AGM, will be released early October.
The society is committed to continue to support students and therefore student travel
grants will be available to subsidise students’ travel costs. Please indicate your interest
for these grants in the Google Form. If you have any questions regarding the travel grants
please get in touch with Michael Martens ([email protected]).
Meteorological Society of New Zealand Newsletter 161 Winter 2020 Page 5
Around the regions NO meetings where organised or attended during Autumn in any
region, due COVID-19 lockdown. ============================================
Autumn NIWA -A dry autumn for most areas of the country Overview Autumn 2020 was characterised by air pressures that were generally near normal over the country and lower than normal over the Tasman Sea. This was associated with slightly more westerly air-flows than normal over the country. There was an on-going lack of rainfall. it was the driest au-tumn on record for Auckland, Tauranga, and parts of southern Otago. The season got off to a hot start, with record or near-record high autumn temperatures recorded during the early days of March, then temperature remained around normal. Autumn average na-tional temperature was 13.4C. Rainfall totals were below normal (50-79% of the autumn normal) or well below normal (<50 % of the autumn normal) in parts of nearly every New Zealand region. The exceptions were West Coast, Marlborough, Wellington and Wairarapa where near normal (80-119% of the autumn normal) rainfall totals were observed
Highlights:
The highest temperature was 32.8°C observed in Cheviot on 3 March. The lowest temperature was -8.2°C, observed at Middlemarch on 31 May. The highest 1-day rainfall was 219 mm, recorded at Milford Sound on 21 May.
The highest wind gust was 161 km/h, observed at South West Cape on 30 April. Highlights and extreme events
Rain, slips and dryness
On 12 March, Agriculture Minister Damien O’Connor classified the drought in the North Is-land, upper South Island, and the Chatham Islands as a large-scale adverse event, unlocking up to $2 Dro.
Heavy rain from 28-30 March across the lower North Island and northern Canterbury result-ed in substantial improvements in soil moisture levels, especially in Wairarapa and Kaikoura.
On 15 April, Watercare reported that Auckland’s nine water storage dams were only 50% full, saying such low levels in April had not been seen since 1994. On 17 April, drought conditions in Northland were reported as the worst experienced there in at least 20 years.
On 7 May, in response to one of the most severe droughts in Auckland’s history, Auckland Council’s Emergency Committee voted to introduce mandatory ‘Stage 1’ water restrictions, pro-hibiting the use of outdoor hoses and water-blasters, as well as the watering of sports fields, plants and/or paddocks.
On 31 May, heavy rain fell in parts of the upper North Island. The Coromandel Peninsula was particularly hard hit and there were numerous reports of slips and debris on the roads through-out the area. SH25 between Hikuai and Whitianga was closed overnight due to flooding, and at least two vehicles were trapped in floodwaters.
Temperatures Between 1-4 March, multiple locations across New Zealand set autumn high maximum tem-perature records or near-records. This was due to warm northerly winds affecting the North Island, while Foehn northwesterlies off the Southern Alps brought hot temperatures to Canter-bury.
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Wind
On 17 March, gusty winds in New Plymouth resulted in a variety of incidents including: a fallen tree blocking part of SH3, loose roofing iron, trampolines becoming airborne, trees falling on powerlines and a roof, and mobile scaffolding blowing across a street and hitting parked cars.
On 15 April, a deep low centred east of the South Island generated strong southerly winds and large swells. Coastal parts of Wellington were inundated by large waves, measured to be at least 5.5 m high by a NIWA buoy near Baring Head. The large waves deposited debris over coastal roads and caused damage to private property, including garage doors and walls. The occupants of five properties were forced to evacuate. One person was swept out to sea, but was rescued shortly thereafter suffering moderate injuries.
On 3 May, strong winds battered much of the country. In South Taranaki, a roof was lifted off a cottage, trampolines were upended, and power lines were downed, causing outages to approximately 150 properties. In Wellington, a strong gust of wind lifted the roof of a house in Crofton Downs, and a tree fell onto Wilton Road. In Auckland, a tree fell into the roof at a home in Hillcrest, while in Paengaroa (Bay of Plenty), a tree came down onto an unoccupied car.
Snow and ice On 23-24 March, light snow occurred behind a southerly change in the lower South Island. Three centimetres of snow was reported in Naseby, with a dusting on the hills near Mossburn.
On 14 April, snow fell to low elevations in parts of Otago and Southland. Approximately 5cm of snow was reported in Kingston, with a dusting on the hilltops near Dunedin. The Milford Road (SH94) and Crown Range Road were temporarily closed due to snow, with a warning in place on SH6 between Athol and Garston due to snow.
Lightning and hail
On 30 March, a lightning strike early in the morning took out power to most customers north of the city of Gisborne in the Gisborne Region. However, power was restored to customers within about 25 minutes.
On 5 May, more than 400 homes in Hawera were without power after a suspected lightning strike damaged the electricity supply.
Cloud and fog
On 14 May, morning fog caused delays for the first wave of COVID-19 alert level 2 domestic flights in and out of Christchurch. =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
MAJOR EVENTS 12th-15th April – Stormy period, including gales, a cold snap, and heavy swells about Wellington Following an active trough crossing NZ overnight 12th/13th, a strong cold southwesterly flow covered the country through to the early 15th. This brought gales to several areas, snow on the hill country of the lower South Island, and by the 15th, heavy southerly swells lashing Wellington’s south coast. On the 12th, an active trough had moved into the Tasman Sea, with a strong, disturbed north to northwest flow over NZ. Gales lashed some areas, with gusts reaching 95 km/hr in Clyde, equal highest recorded for April. Heavy rain fell about and west of the Southern Alps, with 119mm rec-orded at Arthurs Pass. On the 13th, the trough moved to the southeast of the South Island, with a strong colder southwest-erly flow spreading over NZ, which persisted through the next day. This brought squally showers and some thunder and hail mostly to southern and western areas. A thunderstorm also hit coastal South Canterbury on the 13th, with some disruption to mobile phone services due to a lightning strike. Snow fell on the ranges of both islands, reaching quite low down on the hill country in parts of Otago and Southland. A small area as low as about 250-300m at the southern end of Lake Waka-tipu reported a few cm on the ground during the morning of the 14th. The Crown Range and Mil-ford Roads were both closed by the snow briefly on that day. Secretary Island’s 8C maximum on
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the 13th was its lowest on record for April. Gales lashed many exposed areas on both days, with gusts reaching 102 km/hr at Cape Campbell (13th), 93 km/hr in Waiouru (13th), 85 km/hr in Hawera (14th), and 83 km/hr in Palmerston North. (13th) As the trough which earlier crossed NZ moved further to the east on the 14th, heavy swells moved up the east to batter Cook Strait during the day and into the 15th. These big waves (reaching heights of 5.5m at Baring Heads) caused damage about Wellington’s south coast, with debris washed onto coastal roads and several homes having to be evacuated for a time. One person was swept out to sea, but soon rescued. Despite these heavy swells lashing Wellington, the southwesterly flow eased over NZ during the day. Mean sea-level analyses for midday NZST 12th April to 12am NZST 16th April (midnight on 15th April) in 12-hour steps are shown here.
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=========================================================== 2nd-6th May – Trough crosses NZ with stormy weather in many areas Preceded by a strong north to northwest flow, an active trough moved onto and then crossed the country during this period, bringing heavy rain and gales to many areas, followed by a brief cold snap. A complex low-pressure system and trough moved across the South Tasman Sea on the 2nd and 3rd, with a strong disturbed north to northwest flow developing over NZ. Heavy rain set in on the South Island West Coast on the 2nd (73mm recorded in Reefton), spreading to the north and west of the North Island the next day. Flooding was reported in several areas, most notably around Wellington and the Buller Gorge area. Surface flooding briefly closed a section of SH1 through Hamilton. 56mm was recorded in Paraparaumu on the 3rd. The rain was accompanied by gales in many areas, with damage to property reported about Wel-lington, South Taranaki, western Bay of Plenty, and Auckland. Gusts reached 128 km/hr at Secre-tary Island (2nd), 113 km/hr in Hawera (3rd – new May record), and 61 km/hr in Reefton. (2nd) How-ever, the airflow came from low latitudes, so temperatures were well above normal in many areas. High maximums included 25C in Christchurch (3rd), 24C in Cheviot (3rd), 23C in Clyde and Wai-pawa (both on 2nd), 22C in Te Kuiti (2nd) and Martinborough (3rd), and 20C at Southwest Cape, Stewart Island. (2nd) Cloud cover also ensured many places recorded unusually high minimums, including 18C in Kaitaia (3rd), 17C at Western Springs, Auckland (3rd), 16C at Puysegur Point 2nd – a new May record), Farewell Spit (3rd), and Martinborough (3rd), 15C in Akaroa (3rd), and 14C at Southwest Cape. (another new May record) On the 4th, the trough moved onto NZ, with the rain and gales continuing in northern and western areas, with the gales felling a tree onto a car in Whakatane. Rain also spread onto the lower South Island during the day, with the flow tending colder southerly. A cold disturbed south to southwest flow covered the country on the 5th, with thunder and hail in northern and central areas. (some 145 lightning strikes recorded in morning) Lightning strikes cut power to homes in Hawera and South Auckland. A waterspout came ashore on Kapiti Coast and damaged a chicken coop. Recent rains resulted in a slip blocking SH2 over the Rimutaka Hill for a time. Snow fell on the mountain ranges of both islands, falling as low as some of the passes through the Southern Alps. Some 5-10cm fell on Mt Taranaki, as low as about 1200m. During the 6th, the southerly flow eased over the North Island, while tending west to southwest over the South Island, as ridging developed from the west. The weather cleared over most of the coun-try, except for the east of the North Island and the far south. Mean sea-level analyses for midday NZST 2nd May to midnight NZST 6th May (12am 7th June) in 12-hour steps are shown here.
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MONTHLY WEATHER NOTES FOR CHRISTCHURCH: AUTUMN 2020 MARCH Most of the month was dry and settled, but there was significant rain near the end of the month. It was notably cooler than normal thanks to more onshore flows, especial-ly southerlies. Most of the southerlies brought little or no precipitation, but a strong cold change on the overnight 23rd/24th brought a period of rain and even an unseason-ably early dusting of snow about the summit of Mt Herbert and other high Banks Peninsula peaks. A more prolonged damp spell occurred from the 27th-30th, with low pressure to the north and east and an onshore flow. The bulk of the rain fell on the 29th. It was cold again, with snow on the mountains. APRIL This was another very dry month, due to a predominance of westerly flows over NZ. In contrast to March, these airflows brought warmer than normal temperatures, es-pecially during the daytime. Most of the month’s rain fell during the morning of the 18th, in a damp northeasterly flow. A strong cold southwesterly flow from the 13th-15th brought showers and some hail to Banks Peninsula, but none of these reached Christ-church. The mornings of the 14th and 21st were cold enough for light frosts in the city. (the 14th also saw extensive fog in the morning) By contrast, several days reached into the 20s, unusually for April as most of them were late in the month. The only other weather of note were areas of fog and low cloud during the first three days of the month. MAY The trend of drier than normal conditions continued through this month, with day-time temperatures above average, though with colder nights and several frosts during the second half. Almost all the rain fell on two periods. The first being on the 4th/5th when a trough crossed over on the 4th, following by cold, wet southerlies the next day, which brought snow to the inland high country. The second wet spell was on the morning of the 25th, with a light southerly. Morning fog caused disruption at the air-port on the 14th. ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
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Helping the Snow Gods: Cloud Seeding Grows as Weapon Against Global Warming 4 MAR, 2020
Clouds float in the sky above Colorado. Credit: Robert Alexander/Getty Images Winter bonfires paying homage to snow gods have long been a tradition in cold weather regions around the world. But in the last 70 years or so, communities in the west-ern United States have tried cloud seeding, often burn-ing small amounts of silver iodide with the aim of bol-stering dwindling water supplies. The vaporized metal particles are ideal kernels for new ice crystals. When moist, super-cooled air rises over mountain ranges under predictable winds, it sets up perfect conditions for the crystalline alchemy that cre-
ates snow, the white gold craved by ski resorts, ranchers and farmers and even distant cities that need mountain water to survive. Still Controversial But questions remain about how effective it is, and some leading climate scientists say it should not be seen as a meaningful response to climate change Several panels at a recent conference on weather modification addressed some of those issues, and included presentations on how efforts to cooperate on regional cloud seeding projects could serve as a model for governance of even larger scale climate-mitigating geoengineering projects. China and Israel used cloud seeding extensively even before some of the global warming-driven arid-ification trends became clear in the 1980s. Cloud seeding was also weaponized during the Vietnam War, as the U.S. sought to boost rainfall to disrupt supply lines through the jungle. Some Scientists Have Misgivings Research in the last two decades proves that the physical process works, but it's still not clear how much water it produces.Altering clouds with plumes of metallic smoke might work on a localized basis, but it isn't the right solution for large-scale and long-term regional drying and warming, said atmospheric scientist Kevin Trenberth, with the National Center for Atmospheric Research and the University of Auckland, in New Zealand. "If I were concerned about water supply I would not invest in cloud seeding, but rather in manage-ment of water. Cutting down on evaporation from any reservoir, lake, river can be done. Most plac-es have major management issues," he said. "The water is not managed as a system or resource. I am not aware of any studies that show it to be beneficial overall." The WMO scientists concluded that global warming is driving conflicts over water shortages around the world, and that the increased pressure has spurred more interest in cloud seeding https://insideclimatenews.org/news/03032020/cloud-seeding-global-warming More snow on glaciers but no good news, say scientists - NIWA Friday, 6 March, 2020 Scientists have recorded more snow on the South Island glaciers this year, but they warn it is simply a temporary break rather than any good news on the climate change front. NIWA and Victoria University of Wellington scientists completed the annual end-of -summer snow-line survey of 50 South Island glaciers yesterday, taking thousands of photographs to evaluate the snowline altitude and build 3D models of the glaciers. These will be used to assess how much of the previous winter’s snow has remained covering each glacier to contribute toward long-term glacial ice accumulation. The scientists also documented widespread ash coverage on the glaciers as a result of the Australian bushfires. The snowline survey began in 1977 and provides an incredibly valuable long-term record of how New Zealand’s glaciers have retreated over time due to climate change. Dr Lorrey says the ash has coloured many glaciers light orange and may have contributed to the an-nual melt process. http://www.voxy.co.nz/national/5/359734
New Zealand's cooked glaciers, spattered with bushfire ash
Meteorological Society of New Zealand Newsletter 161 Winter 2020 Page 12
06 March 2020, Eloise Gibson In 2019 NIWA's annual end of summer snowline survey showed many glaciers were affected by a historically warm summer. 2020's findings showed the glaciers in better shape, but still declining
over the long term. NIWA Ash from the Australian bush fires forms a pink coating over the Southern Alps.
Although the annual flights have become a powerful indicator of a heating planet, glacier scientist Trevor Chinn wasn't thinking of climate change when he came up with the idea of flying over about 50 glaciers and taking their photos. Chinn wanted to understand the ice that gives the South Island its precious freshwater reservoirs. By
the time he died, in 2018, his survey showed the glaciers had collectively lost a third of their mass in four decades.
The problem, he says, is that the bad years aren't being balanced out by equally good years. NIWA Climate scientist Drew Lorrey photographs glaciers for Niwa's an-nual snowline survey.
The ash is a reminder of the dry condi-tions that will get worse with climate change,. Lorrey and the other re-searchers, such as Victoria University's Lauren Vargo, are here to look for the snowline. A lower snowline means there's more compressed snow left at
the end of summer to rebuild the glaciers. Since the snowline has retreated up the mountain since the bushfires, there's pink dust on the rem-nant snow, but not the lower, icy layer below it. The line between white and pink makes it easier to see where the old snow ends. "This would be a great year to teach someone how to find the snow-line," says Lorrey. https://www.stuff.co.nz/environment/climate-news/120059963/climate-crisis-in-one-shrinking-glaciers-spattered-with-bushfire-ash NASA, New Zealand partner to collect climate data from commercial aircraft using GNSS
08 March, 2020 Image courtesy of NASA. NASA is partnering with the New Zealand Ministry of Business, Innovation and Employment, New Zealand Space Agency, Air New Zealand and the University of Auckland to install next-generation Global Navigation Satellite System (GNSS) reflectometry receivers on pas-senger aircraft to collect environmental science data over New Zealand. The program is part of NASA’s Cyclone Global Naviga-
tion Satellite System (CYGNSS) mission, a constellation of eight small satellites, launched in 2016.The CYGNSS satellites orbit above the tropics and their primary mission is to use GPS sig-nals to measure wind speed over the ocean by examining GPS signal reflections off choppy versus calm water. This allows researchers to gain new insight into wind speed over the ocean and will allow them to better understand hurricanes and tropical cyclones. Special receivers will be installed in late 2020 on one of Air New Zealand’s Q300 domestic air-
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craft. As the aircraft traverses New Zealand, it will collect data from the land below, some of which will overlap with the flight paths of the CYGNSS satellites. This overlap, which will have frequent data observations from regular commercial flights, will provide the CYGNSS team a wealth of data to use to validate and improve the CYNGSS satellite observations. https://www.spacetechasia.com/nasa-new-zealand-partner-to-collect-climate-data-from-commercial-aircraft-using-gnss/ Chance of decent weekend rain for northern areas hardest hit by drought
10 Mar 2020, Michael Daly "For this coming weekend we are expecting a weather system to bring some rainfall over the ( drought-affected) northern parts of the North Island," Met-Service meteorologist Mmathapelo Makgabutlane said. AMANDA SAXTON https://www.stuff.co.nz/national/120156333/chance-of-decent-weekend-rain-for-northern-areas-hardest-hit-by-drought
Cyclone Gretel to bring some rain, strong wind to North Island
15 Mar, 2020 Cyclone Gretel is set to douse parched areas of the North Island with some much-needed rain this
week - but not nearly enough. Located the northwest of New Caledonia on Sunday morning, Gretel is expected to move towards the North Island late Mon-day evening. The tropical cyclone will brush New Zea-land on Tuesday and is expected to bring rain to the north of the country, Met-Service forecaster Paul Ngamanu said. But it won't be anywhere close to the sub-stantial amount desperately needed in tin-der-dry areas of the North Island, recently classified as experiencing a "large-scale ad-verse event".
https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12316841
Fallen tree blocks SH5, Clifton Beach closed amid high winds
17 Mar, 2020, Hawkes Bay Today By: Christian Fuller Traffic was brought to a standstill after a tree fell on State Highway 5, near Waipunga, while a Hawke's Bay beach was closed due to high winds. MetService had a strong wind watch warning in place from 8am Tuesday to 4am Wednesday and it caused a few problems. Axel Alexander came across the tree about 12.20am on Tuesday morning. A MetService spokeswoman said the warning was in place to give people a heads-up about potential-ly hazardous driving conditions, debris which may blow around and time to tie down any outdoor items. https://www.nzherald.co.nz/hawkes-bay-today/news/article.cfm?c_id=1503462&objectid=12317278
NIWA needs volunteers for data entry
20 March 2020 NIWA climate scientists are asking for volunteers to help with a historic weather project. The scientists have accumulated a mass of weather data for a special project focused on a week in July 1939 when huge snow-storms blanketed the country - but the problem is the records are all handwritten and now need to be keyed into a computer. NIWA climate scientist Dr Andrew Lorrey says there is much to be learned from historic weather that can help predict climate patterns today and into the future. "For instance, was 1939 the last gasp of conditions that were
common during the Little Ice Age which ended in the 1800s? Or the first glimpse of the extremes of climate change thanks to the Industrial Revolution?" The July 1939 snowstorm project - named The Week It Snowed Everywhere - are significant because of the extent of the snow. There were flurries recorded at Cape Reinga lighthouse, 5cm of snow rec-orded on the top of Mt Eden, Auckland and in Dunedin residents had to clear at least 100mm of snow from the streets. For more information visit: www.southernweatherdiscovery.org https://www.sunlive.co.nz/news/237612-niwa-needs-volunteers-data-entry.html
Dynamic Weather On World Meteorology Day
23 March 2020 MetService are forecasting a duo of southerly fronts this week, making for colder and wetter condi-tions – some active weather to mark World Meteorology Day (Monday 23 March). Today, the front is being forecast as a “southerly buster” as it travels up the South Island east coast. A colloquial term frequently used by Southern Hemisphere meteorologists, a buster refers to a dra-matic southerly change, abruptly delivering very strong winds, sharp temperature drops and a burst of rain. It’s also not uncommon for a few rumbles of thunder. MetService meteorologist Tui McInnes explains: “Today’s buster up the South Island will be a ra-ther significant change in the weather, especially for those around the coast. We are expecting strong wind gusts of up to 90 km/h in exposed locations.” https://www.scoop.co.nz/stories/AK2003/S00407/dynamic-weather-on-world-meteorology-day.htm Steep improvements seen in Auckland air quality - NIWA Monday, 30 March, 2020 NIWA scientists say air quality has dramatically improved in Auckland since the COVID-19 Level 4 lockdown was instigated. In less than a week a steep drop in nitrogen oxide has occurred, particular-ly in suburban Auckland. NIWA air quality scientist Dr Ian Longley says nitrogen oxide is found in pollutants from vehicle exhausts. They exacerbate asthma and are linked to numerous health im-pacts. "At the Takapuna monitoring site, close to the Northern Motorway, nitrogen oxide levels at the end of last week were about a third lower than that normally seen during the morning rush hour. For the remaining daylight hours they were reduced by up to 80 per cent." http://www.voxy.co.nz/national/5/361594
MetService hits pause on Otago weather radar
30 March 2020, By John Lewis MetService has halted construction of its $2.8 million weather radar in Otago as a result of Covid-19 and the country going into lockdown. Construction on Lamb Hill, near Hindon, was in full swing and the project was running to schedule. MetService meteorological data services manager Kevin Alder had anticipated the radar would be operational by late May this year, but that date would now be considerably later. "The delay was unavoidable," he said. https://www.odt.co.nz/news/dunedin/metservice-hits-pause-otago-weather-radar
We've slowed climate change once. Can we do it again?
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We've slowed climate change once. Can we do it again? Apr 01 2020, Olivia Wannan11:19, A new study from the University of New South Wales has found that in addition to allowing the ozone layer to recover, the Montreal Protocol has also slowed the rate of climate change by up to 25 percent. The world has successfully halted human-made changes to the southern jet stream that left New Zea-land increasingly prone to drought, a new study concludes. But if we don't cut greenhouse gas emissions, the researchers say, any improvement may be tempo-rary. A new study, which was published in the scientific journal Nature, examined the position of the southern hemisphere's jet stream, a fast-moving air current that can play havoc with New Zealand's weather. This air stream varies from year to year, but had been moving south courtesy of the ozone hole. Ozone and climate scientists have kept an eye on the southern jet stream. As there was less ozone to react with ultraviolet rays from the sun, the upper atmosphere above Antarctica cooled, triggering the jet stream's migration towards the icy continent. The new study found, from the turn of the mil-lennium, this drift came to a halt. Between 1980 and 2000, the jet stream shifted approximately 220 kilometres towards the south pole during the summer. The air current influences the number of low-pressure weather systems, known for bringing storms and chilly weather, that pass over New Zealand. As these lows became less likely to arrive, especially in northern regions, our temperatures rose and our rainfall fell, leaving the country increasingly prone to drought. Northern regions experienced a record-breaking warm and dry summer this year.
NASA The ozone hole affected the southern hemisphere's jet stream, con-sequently making New Zealand both warmer and drier. Study co-author and Cooperative Institute for Research in Environ-mental Sciences researcher Dr Antara Banerjee said the data indicated that, from the year 2000, the jet stream's drift "has not only paused, but might even be reversing … moving back towards the equator" as the ozone hole repairs itself.
MetService hits pause on Otago weather radar 01 April 2020, Mike Watson MetService has halted construction of its $2.8 million weather radar in Otago as a result of Covid-19 and the country going into lockdown. Construction on Lamb Hill, near Hindon, was in full swing and the project was running to schedule. MetService meteorological data services manager Kevin Alder had anticipated the radar would be operational by late May this year, but that date would now be considerably later.
DAVID WHITE/STUFF At least 10 records for hot temperatures and dry conditions were broken in Northland and Auckland during the summer. Banerjee said the research proved the world had the power to avert large-scale climate impacts. "The success of the Montreal Protocol should send a powerful message to governments that they have the ability to reverse the damage that we have done to our planet, only if they cooperate effec-tively and honour their commitments with strong action," she said. Commenting on the research, Niwa ozone scientist
Dr Olaf Morgenstern said this summer's extreme dry weather was "made more likely" but not solely caused by the ozone hole. The migrating jet stream was one contributing factor to New Zealand's changing climate, Morgen-stern said. "Under global warming, there are other reasons why drought might become more preva-lent," he said. Though the ozone hole worsened the effects of climate change, greenhouse gas emissions will have the biggest impact on our country's risk of drought and other extreme weather in future. Ozone-depleting chemicals were phased out after the international Montreal Protocol agreement was
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signed in 1987. Although banned chemicals may still be in use, Morgenstern said the decline was "a little slower than we had hoped for" but steady. "It's going down, which is better than going up." https://www.stuff.co.nz/environment/climate-news/120682952/weve-slowed-climate-change-once-can-we-do-it-again Auckland and Northland drought: Water reservoirs half full, more dry weather forecast 1 April 2020 Water storage in Auckland and Northland is critically lower than the historical average and looks set to drop even further as more dry weather is forecast for the regions. The persistent dry patch, which began in November, means western Northland and parts of Auck-land are still withering in a meteorological drought. And even with the advent of autumn, Niwa meteorologist Ben Noll said there was still no significant rain on the horizon. "The first week of April is quite dry, and while the second week has some fronts with showers, none are particularly heavy or the type of rain to break this dryness we are in," he said.
Critically low: Wairoa Dam in Auck-land's Hūnua Ranges. Noll said the regions were unlucky to miss the path of two ex-tropical cy-clones, Uesi and Gretel, earlier this year. https://www.stuff.co.nz/environment/climate-news/120696942/auckland-and-northland-drought-water-reservoirs-half-full-more-dry-weather-forecast Cyclone to bring strong winds and rain 4 Apr, 2020 This morning Cyclone Harold was
about 295km west of Torres and 325km west northwest of Santo. The Vanuatu Met Office said the category storm was generating damaging gale force winds gusting to 160km/h. Acting Police Commissioner Mostyn Mangau told the Solomon Star people they need to take all pre-cautions especially those living close to river banks to move to high grounds immediately. "Do not try to cross rivers with an unknown depth. This is too risky. If the flood risk increases, make plans move to higher grounds. Do not allow children to play in the rain or near the rivers or along the drains," he said.
Tracking map for tropi-cal cyclone Harold af-fecting Solomon Is-lands as it heads to Va-nuatu. "Stay on alert and watch out for land-slides which could be caused by the continu-ing heavy rain espe-cially those living on hillsides. Make sure you tie down any loose material that might be blown by the wind causing a danger to other people." https://www.nzherald.co.nz/world/news/
article.cfm?c_id=2&objectid=12322498
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arold intensifies to category two storm, aims for Vanuatu and Solomon Islands 4 Apr, 2020 2:30pm
Solomon Islands coastal regions have taken a batter-ing from Cyclone Harold Cyclone Harold has intensified to a category two system, with winds of up to 160kph, as it makes it way between Solomon Islands and Vanuatu. The system had already caused a lot of damage in Solomon Islands and was now headed towards Va-nuatu. The latest tracking threat map indicated it will be a category 3 by the time it reaches Vanuatu. Meanwhile, 28 people were still missing from Solomon islands in the middle of the cyclone. The MV Taimareho left the capital Honiara on Thursday evening bound for West Are'are on Ma-laita. Early on Friday morning it encountered ex-treme weather conditions generated by Cyclone Harold and some of its passengers were swept over-board.
Latest satellite image of Tropical Cyclone Harold near Vanuatu. The system is swirling over Solomon Islands. https://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=12322498
Cyclone batters Vanuatu, heads towards Fiji
4 April 2020 Cyclone Harold brings strong winds in Luganville, Vanuatu, Adra Vanuatu via REUTERS. Tropical Cyclone Harold lashed the South Pacific island of Vanuatu for a second day on Tuesday, rip-ping off roofs and downing telecommunications, and was moving towards Fiji where it is expected to slightly weaken. The powerful cyclone made landfall on Monday in Sana province, an island north of Vanuatu's capital Port Vila, with winds as high as 235kmh knocking out communications overnight, according to reports by the government's disaster and weather bureaus.
The winds blew roofs off houses, tore down trees and destroyed a council building in Luganville. https://www.odt.co.nz/star-news/star-international/cyclone-batters-vanuatu-heads-towards-fiji Cyclone Harold updates: Storm makes landfall on Vanuatu's Santo 6 April 2020 Jamie Tahana, RNZ Pacific Journalist
Cyclone Harold, the most powerful storm in the Pa-cific in at least two years, has made landfall on the Vanuatu island of Santo, with winds gusting as high as 235km/h. Cyclone Harold - a category five, the highest possible - has sat just to the west of Vanuatu's central islands for much of the past day, gathering significant strength in the past 12 hours. TC Harold hit Santo and washed domestic vessels ashore, Santo Island Vanuatu :Ryry Titus
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Forecast tracking map for Tropical Cyclone Har-old Photo: Fiji Meteorological Service https://www.rnz.co.nz/news/pacific/413549/cyclone-harold-updates-storm-makes-landfall-on-vanuatu-s-santo Cyclone Harold batters Fiji on path of destruction through Pacific Thu 9 Apr 2020 Cyclone Harold has levelled buildings and caused dangerous flooding across Fiji’s largest island of Viti Levu, after pummelling Vanuatu as a category-five
storm on Monday. The tropical cyclone was downgraded to category four before reaching Fijian waters.. Frank Bainimarama, the country’s prime minister warned earlier on Wednesday that “the worst of TC Harold will strike Fiji through this afternoon … Flying debris and floodwaters can be deadly. All
Fijians should stay indoors unless directed to evacuate.” Not too long ago around our cafe in Ba @MaiLifeMagazine #TCHarold #fiji Harold was expected to hit Tonga in the next 48 hours. The Matangi Tonga web-site reported that Harold’s arrival in the country would coincide with a king tide and a supermoon early on Thursday morning. An extreme high tide warning was in force for Tonga for Thursday and Friday. https://www.theguardian.com/world/2020/apr/08/cyclone-harold-batters-fiji-on-path
-of-destruction-through-pacific Stunning twist: Cyclone Harold returns to Category 5 strength as it passes Tonga
9/04/2020 Overnight severe cyclone Harold strengthened further despite moving away from the equator and tracking south east towards Tonga. Harold gained power as it departed Fiji last night, moving away from land and over very warm sea wa-ters just shy of 30 degrees. It’s here that it re-energised back to the most power level, Category 5. There is some good news for Tonga today – the centre of the storm has remained south, meaning the most destructive part of the storm was just shy of the main island. The bad news is that coastal flooding could be
‘catastrophic’ in some spots and wind damage may have also been significant. https://www.weatherwatch.co.nz/content/stunning-twist-cyclone-harold-returns-to-category-5-strength-as-it-passes-tonga MetService has issued snow warnings for several South Island mountain passes 13 April 2020 Lewis Pass and the Crown Range Road are in for about 2cm of snow overnight around their sum-mits. About 1cm of snow is likely at the top of Arthurs Pass tonight. About 2cm of snow is expected overnight on The Milford Road around the tunnel. . https://home.nzcity.co.nz/news/article.aspx?id=309756
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Pacific's monster storm destroys tourist resorts in Tonga 14.04.2020
A picture taken and released by the Tonga Police on April 9, 2020 shows damage to a tourist resort caused by Tropical Cyclone Harold in the Hihifo coastal area -- police said three resorts were re-duced to rubble / © TONGA POLICE/AFP A resurgent Tropical Cyclone Harold flattened tourist resorts in Tonga Thursday, extending a week-long trail of destruction across four South Pacific island nations that has claimed more than two dozen lives. "It's been a tricky one to predict," meteorologist Bill Singh from New Zealand's Metservice told
AFP. "We knew the track it was going to take but initially every-one thought it was just going to be Cat 3 or 4, but as it progressed over open warm waters it deepened." Tropical Cyclone Har-old / © AFP https://today.rtl.lu/news/science-and-environment/a/1498586.html
Person taken to hospital after being knocked over by massive waves at Owhiro Bay, Wellington 15 Apr, 2020 10:50am By: Melissa Nightingale A person has been taken to hospital after being knocked over by freak waves on Wellington's south coast. A Wellington Free Ambulance spokeswoman said the patient was in a moderate condition after be-ing "swept out into the water".
But a police spokesman said the person had simply been knocked over by the wave. Five homes have been evacuated and the public have been warned to stay away as large swells crash over the road and footpaths between Breaker and Owhiro Bays. Huge swells rolling into Owhiro Bay on Wellington's South coast, causing extensive damage to roads and vehi-cles, on Day 21 of the Covid-19 coronavirus lockdown. Photo / Mark Mitchell The swells were expected to peak at midday at 6 metres, "which is really quite high".
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A worker attempting to clear debris dumped by huge swells rolling in to Owhiro Bay on Wellington's south coast. Photo / Mark Mitchell Weather in the capital couldn't be nicer - sunshine and light breezes - but the waves were being pushed by forc-es further away from the country, MetService meteorol-ogist Andy Best said. The huge swells originated south east of the South Is-land, MetService meteorologist Gerard Bellan said. A deep low pushed up a big surge of water which gained
energy and intensity as it rushed up the country. KEVIN STENT/STUFF Huge waves at high tide caused damage and left large debris on the Espla-nade between Island and Ōwhiro Bays. Niwa meteorologist Ben Noll said the situation had been further exacerbated by an already high water level. "When large waves break, there is an increase in wave set-up. The water level becomes elevated, allowing waves to come further inland. This is in addition to having slightly elevated tides on the back of King Tides a few days ago."
https://www.stuff.co.nz/dominion-post/news/wellington/121042720/what-caused-wellingtons-extreme-waves First snow, then rainbows: Hawke's Bay's autumnal weather
17 Apr, 2020 5: By: Christian Fuller A rainbow in Hatuma, near Waipukurau on Thursday signals a warm autumnal end to the week. Photo / Kiri Kirk In a week where Hawke's Bay received its first light dusting of snow on the Ruahine mountain range, weekend temperatures are set to hit 25C. https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12325680
Smoke from Australia's bushfires continues to travel globe APR 23, 2020, BY GERMAN PRESS AGENCY DPA
Aluminum (which melts at 660C) seen streaming from a burnt car in Conjola Park, a town where bushfires razed over 89 properties, in New South Wales on Dec 31 2019. Smoke from the bushfires that ravaged Australia in late 2019 and early 2020 has continued to circle the globe almost four months after it was first formed, scientists have found. New Zealand's National Institute of Water and At-mospheric Research (NIWA) scientist Richard Querel said in a statement Thursday it was re-markable to be able to track a smoke plume for more than 100 days. "The fires were so energetic they injected smoke
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and carbon aerosol into the stratosphere, which has since risen to about 35 kilometers (22 miles) above the earth," he said. He said at its height the main bulk of the plume was about 5 km high and hundreds of kilo-meters wide. The smoke had now been around the globe "a few times" with the remnants currently over South America, Querel said. An estimated 830 million tons of carbon dioxide were released into the atmosphere between September and February due to the devastating fires, according to a preliminary estimate by the Department of Industry, Science, Energy and Resources released this month. Australia's greenhouse gas emissions are equivalent to about 540 million tons of carbon dioxide per year, according to a policy brief published in October by the Australian National University. https://www.dailysabah.com/life/environment/smoke-from-australias-bushfires-continues-to-travel-globe 'Good weather recipe' for North Island's Anzac weekend, 'pair of pesky fronts' hit south 24/04/2020 Jamie Ensor The last weekend of lockdown will see most of New Zealand relax in "settled" weather, with sunny spells across the North Island. Metservice forecasts "cloudy mornings" but "fine afternoons" this weekend. https://www.newshub.co.nz/home/new-zealand/2020/04/weather-good-weather-recipe-for-north-island-s-anzac-weekend-pair-of-pesky-fronts-hit-south.html Rain to dampen first weekend of level 3 1 May, 2020 By: Ben Leahy Kiwis might have gained their first weekend of relative freedom under alert level 3, but wilr, includ-ing thunderstorms, is set to put a dampener on those mountain bike rides and walks. MetService expects heavy rain, cold temperatures and storms to hit much of the country by Sunday, after a fine few days. "With a couple more days of fine weather ahead it's a good idea to clear any gutters or drains as many places will see a spell of heavy rain over the weekend," said meteorologist Lewis Ferris.
Heavy rain is coming to much of the North Island on Sunday evening and Monday. Photo / 123RF Auckland can expect a top of 20C today and then a cloudy Saturday with a top of 21C before show-ers kick in over the afternoon. On Sunday, the showers will turn to possible heavy rain and strong winds that will carry on into Monday. Unfortunately, the weekend showers are unlikely to be enough to top Auckland's dams, which were less than half full four days ago. A broad trough of low pressure is set to to bring significant weather across Aotearoa this weekend. Heavy rain and gale winds are expected for many places Aucklanders have been heeding calls to save water, but without prolonged and significant rain, they may need to continue their water-saving ways. Much of the country will also receive a "healthy dose" of rain, with decent showers expected in cen-tral areas including Manawatū and Northland. Hamilton and Tauranga are also likely to see heavy rain on Sunday and Monday, with temperatures over the next four days in the low 20 degrees Celsius.
A plume of subtropical moisture will affect much of New Zealand from Saturday-Monday Less rain should fall on Hawke's Bay, where falls will develop in Napier and Gisborne on Sunday
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with both cities experiencing temperatures between 21C-23C over the next four days. Wellington will experience a similar pattern, with patches of Friday cloud strengthening on Satur-day, before rain, possibly heavy, on Sunday. However, temperatures will be a lot lower, between 17C-18C over the next four days, dropping down to a rainy 12C next Wednesday. Christchurch residents can enjoy the first weekend of alert level 3 with mostly fine weather apart from a few spots of rain on Saturday and temperatures between 21C-23C. https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12328755 Heavy rain and strong winds hit both islands, causing damage and slips May 03 2020, Tina Law George Block Danielle Clent17:13,
KEVIN STENT/STUFF Northerly winds and a high tide causes waves to crash over the sea wall at Balaena Bay in Welling-ton. Trustworthy, accurate and reliable news stories are more important now than ever. Support our newsrooms by making a contribution. A tree has smashed into a roof and a building is flooded as wild weather lashes the country. Fire and Emergency NZ shift manager Craig Dally said the occupants escaped injury when a tree fell into the roof at a home in Hume Dr in Auckland's Hillcrest about 3.30pm. Firefighters managed to get the tree off the roof using a chainsaw, he said. Across the city, about 20 minutes later, firefighters were deployed to a flooded building in Karangahape Rd, Dally said. Heavy rain and gales are battering both islands, closing roads, lifting roofs and causing flooding. Metservice said strong winds, rain and possible thunderstorms would hit the West Coast, Taranaki, Auckland and the wider Wellington region from Sunday through to Monday.
RICKY WILSON/STUFF Aucklanders did not need much encouragement to stay home as wild weather lashed the city on Sun-day afternoon. Drought-stricken Northland was expected to have periods of heavy rain from midday and towns such as Kaitaia could experience thunderstorms. Parts of Canterbury have also been buffeted by high winds, creating high waves on waterways in-cluding Lake Tekapo. Wellington, southern Wairarapa and Marlborough were being affected by strong gusts on Sunday morning, MetService said, while in Taranaki powerlines were down and at least one roof lifted off a house.
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A man crosses Fanshawe St in Auckland's CBD on Sunday afternoon. There were heavy rain warnings for Taranaki, Tongariro National Park, the Kaimanawa Range, and the eastern Bay of Plenty Ranges. Watches for gales were issued for Marlborough, Wellington, southern Wairarapa, Taranaki, Taihape and the Whanganui hill country, and Auckland. The strong wind watch for Auckland is in place from 1pm.
KEVIN STENT/STUFF Wild weather hits Wellington. A pedestrian makes a dash across Ghuznee Street. MetService said strong to gale force northeasterly winds are expected until 7pm and "gusts may ap-proach 100 kilometres an hour in exposed places". Auckland Emergency Management said people in the region may have noticed the rain and wind picking up. It advised people to contact Auckland Council if public trees had been blown down or Vector for power outages.
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THE-PRESS A slip is on the move in the Lower Buller Gorge. New Zealand Transport Agency (NZTA) contractors were hoping to clear the slips by early Sunday afternoon if weather conditions allowed. SH6 south of Westport to Greymouth is open, but rain was continuing to fall in northern Westland and Buller district. “We encourage people to avoid using the roads in these conditions and please be on the lookout for surface debris. Slow down if you do have to make a journey,” NZTA maintenance contract manager Moira Whinham said.
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THE-PRESS Recent High winds have created waves on Lake Tekapo. PHOTO: GEORGE EMPSON Heavy rain could cause streams and rivers to rise rapidly. Surface flooding and more slips were also possible and driving conditions could be hazardous, MetService warned. SH67, north of Westport to Mohikinui, has also had some surface flooding but it remains open. The road south of Inangahua was closed earlier today due to flooding between Inangahua and Reef-ton. The road opened at 9.30am. https://www.stuff.co.nz/the-press/news/121388861/weather-heavy-rain-and-strong-winds-hit-both-islands-causing-damage-and-slips Wellington And MetService Lead The Way On Improved Coastal Warning System 3 May 2020, A wave-warning alert system has been initiated on Wellington’s south coast and exposed parts of Wellington Harbour, including the Eastbourne-Pencarrow coast, as a result of the damage caused in Owhiro Bay last month by big swells driving through Cook Strait. MetService is to provide the swell warning to the Wellington Regional Emergency Management Of-fice, Greater Wellington Regional Council, Wellington City Council and Hutt City Council. Additionally, MetService will provide trial access to its oceanographic portal for six months, devel-oped specifically for maritime and governmental agencies by their sister company, MetOcean Solu-tions, for forecasting offshore and near shore wave conditions. The initial agreement was reached on Friday in a second meeting involving Owhiro Bay Residents Association representative Eugene Doyle, representatives from MetService, WREMO and the City Council, and Paekawakawa Southern Ward Councillors Fleur Fitzsimons and Laurie Foon. It is intended that MetService data would be used to provide public warnings to seaside communities and to residents’ associations. Representatives from the organisations will meet to discuss details of the trial in the next week or so. Mayor Andy Foster says: “I’d like to congratulate Eugene and all the parties who’ve got together in the past couple of weeks and worked hard towards this initiative.” Mayor Foster adds that the new warning system will undoubtedly be looked at with interest by coun-cils and emergency organisations in other parts of the country. Meanwhile WREMO staff have undertaken to provide a report in a week’s time that will cover what happened, what needs to be done to improve the current alert system, and what else can be done with South Coast communities to help reduce risk and improve their level of preparedness. City Council officers also undertook to take advice on the feasibility of managing the grade of the beach following requests from some local residents, who felt this might mitigate future events. Mayor Foster adds he also intends to discuss with Council staff the implications of the wave damage to the track from Owhiro Bay to Paiwhero Red Rocks and tackling the build-up of gravel under the Owhiro Stream bridge. Hutt City Council says it welcomes the wave-warning initiative. The group that met on Friday via teleconference will meet again next Friday 8 May. https://www.scoop.co.nz/stories/AK2005/S00058/wellington-and-metservice-lead-the-way-on-improved-coastal-warning-system.htm Trees fall on to cars as wild weather lashes Bay of Plenty 4 May, 2020 By: Sandra Conchie
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Wild weather in Bay of Plenty Wild weather wreaked havoc overnight in the Bay of Plenty, including an emergency call out to a tree that had fallen on to a car. A Fire and Emergency New Zealand shift manager said the tree came down on State Highway 33 in Paengaroa just after 7pm. The road was cleared by Maketu firefighters using a chainsaw. No one was inside the vehicle at the time. Powerlines also came down in Ngamotu Rd in Taupō about 6.30pm, but it was believed a car may have hit a power pole. However, no car was located when the fire crew arrived on the scene, she said. A tree also came down in hit an unoccupied parked car in Rambler Drive, Whakatāne, at 1.30am to-day. Mount Maunganui Fire Brigade was also called to a car fire in Ranch Rd, Mount Maunganui at just after 2am. MetService meteorologist Tui McInnes said wind gusts of just under 60km/h were recorded in Tau-ranga Airport about midnight. At Rotorua Airport, MetService recorded gusts of just over 80km/h. McInnes said two hours later, after a second front crossed the central North Island, wind gusts of just under 65km/h were recorded at Whakatāne Airport. In the 12 hours to 7am today, 27mm of rain fell in the Rotorua inland area towards the east, 7mm in Whakatāne and 5.2mm in Tauranga In the Bay of Plenty's Kaimai Range and eastern ranges about 40 to 50mm of rain fell. McInnes said there was a chance of local wind gusts later today but nowhere near as strong as over-night. https://www.nzherald.co.nz/bay-of-plenty-times/news/article.cfm?c_id=1503343&objectid=12329281 Drought: Rainfall 'lowest ever' in much of North Island May 05 2020, Denise Piper16:21, The north of the North Island is in a prolonged drought. Trustworthy, accurate and reliable news stories are more important now than ever. Support our newsrooms by making a contribution. The North Island drought — the worst in 50 years in some parts of Northland — has prompted thou-sands to seek financial help. This year's drought has hit far, hard and wide, said Ben Noll, meteorologist for the National Institute of Water and Atmospheric Research (Niwa). Whangārei, Auckland, Whitianga, Hamilton, Tauranga, Whakatāne, Napier and Taupō have had their driest January to April on record, according to Niwa's figures.
Brown grass has become the norm in Hawke's Bay, prompting the Hawke's Bay Regional Council to encourage water storage. Other regions hit hard by the drought include the Far North, Waikato, Gisborne, Hastings and
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Marlborough, Noll said. Auckland was particularly hard hit with more than 77 consecutive days spent in drought or severe drought, according to the New Zealand Drought Index. Auckland has been hard hit by the drought, with water running dry - such as the Upper Manga-tawhiri Dam in the Hunua Ranges, which is about 45 per cent capacity. In 2013, which was the worst drought in 40 years, Auckland experienced 58 consecutive days of drought. The drought has had a big impact on rural families who rely on rainwater tanks, with thousands needing help to pay for refills. The Ministry of Social Development has given $681,000 to 1712 New Zealanders in water tank refill payments since the start of the year. The highest number of clients (747) were in Northland, where the average refill costs were highest and nearly 200 clients needed more than one grant for multiple refills.
DENISE PIPER/STUFF Washing dishes in a bowl so the water can then be used on the garden is common practice for house-holds short on water, including those on tanks and towns like Kaitaia with water restrictions. There were also 621 clients in Auckland, 81 in Waikato and 263 across the rest of New Zealand, ac-cording to the provisional figures. On top of these payments for water, the ministry paid $42,257 to 29 farmers and growers in hardship, under the Rural Assistance Payments. The payments are for the likes of farmers to help them put food on the table in this difficult time, Northland Rural Support Trust co-ordinator Julie Jonker said. Much more than just 29 farmers would qualify the grant, and she urged farmers to apply for what they are entitled to, instead of holding back. "In some ways there's a lack of wanting to apply because, for some people, it's admitting that you can't cope. But that's not the case: It's an extraordinary drought — in some places, the worst in 50 years — so don't be ashamed to apply for it." Jonker praised the ministry for giving the grant to farmers before they used all their working capi-tal, which meant there would still be some funds left to reinvest in the farm once drought conditions ease. In Northland, autumn rains have so far done little to quench the need for rain. Unlike Auckland which had a large amount of rain on Sunday, just 15mm fell in central Whangārei, much less than the 50mm expected. The drought comes on top of record low rainfall in 2019, making the current situation so severe the region has had 1000mm less rain than usual since January 2019, water services manager Andrew Venmore said. “People have rightly been occupied by the Covid-19 levels over the past six weeks, but attention needs to come back onto the water situation in Whangārei as well, because that situation keeps get-ting worse."
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WHANGAREI DISTRICT COUNCIL An aerial view of Whangarei's Whau Valley dam shows sandbanks where there should be stored wa-ter, with the dam just 44 per cent full. All of Northland is under mandatory water restrictions, with all of Kaipara, the Far North towns of Kaitaia, Rawene, Kaikohe and Kawakawa, plus 23 coastal communities, under the toughest re-strictions available. For these areas, outdoor water use is banned and water can only be used for essential use. But other areas are not out of the clear either, with Whangārei's dam at Whau Valley being just 44 per cent full. The city has a hose and sprinkler ban. The Northland Regional Council said rivers are particularly low in Bream Bay, Whangārei and some of the Far North, with most rivers between 80 and 90 per cent below normal flows. Some parts of Northland are experiencing an "extreme" one-in-50-year-drought, according to re-gional council figures. “A dry winter in 2018 preceded by a dry year in 2019 were the perfect set-up conditions for the drought currently gripping the region,” natural resources monitoring manager Jason Donaghy said. The council is urging people to think ahead to next summer and consider extra storage options, such as tanks and dams, to protect against extreme water shortages again next year. https://www.stuff.co.nz/environment/climate-news/300004696/drought-rainfall-lowest-ever-in-much-of-north-island Drought hits hard, far and wide - NIWA Tuesday, 5 May, 2020 Analysis of drought conditions across New Zealand this year shows it is one of the most severe on record for some regions. And while conditions have improved in most regions, NIWA meteorologist Ben Noll says river flows and soil moisture levels remain below normal for large parts of the North Island and upper South Island while before last weekend drought still persisted in the Coromandel Peninsula. NIWA meteorologist Ben Noll says figures show this year’s drought is notable for its wide reach and long duration. "For some parts of the country this year’s drought was similar to the one in 2013 which was the worst in 40 years. This has hit hard, far and wide," he says. The 2013 drought affected the entire North Island plus the west coast of the South Island. This year the impact wasn’t quite as extensive but did range from the Far North to Canterbury. Auckland has been particularly hard hit with more than 77 consecutive days spent in drought or se-vere drought, according to the New Zealand Drought Index. In 2013 the region experienced 58 con-secutive days of drought. A number of North Island locations recorded their driest January-April on record this year, includ-ing Whangarei, Auckland, Whitianga, Hamilton, Tauranga, Whakatane, Napier, and Taupo. Other regions hard hit by drought this year include the Far North, Waikato, Gisborne, Hastings and Marlborough. The most consecutive days in drought or severe drought during the longest droughts since 2007 are (according to the NZ Drought Index): Far North District: 72 days (2009-10), 65 days (2020), 40 days (2013) Auckland: 77 days (2020), 65 days (2010), 58 days (2013) Waikato District: 63 days (2013), 61 days (2020), 52 days (2014) Gisborne District (west): 47 days (2013), 37 days (2020), 12 days (2015) Hastings District (west): 33 days (2013), 29 days (2020) Marlborough District (south): 35 days (2020), 9 days (2019)
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Mr Noll said the drought was caused by several factors including persistent, blocking high pressure systems in the northern Tasman Sea and north of the North Island, suppressing rain-bearing weather systems to the south. There was also a lack of moist, northerly air flows and a persistently positive Southern Annular Mode early in the year which was associated with more tranquil weather in the New Zealand re-gion. NIWA climate scientist Petra Pearce says this year’s drought highlights the projections from NI-WA’s regional climate modelling for northern and eastern areas of New Zealand (particularly the North Island) to become more drought-prone with ongoing climate change over this century. "Average rainfall is projected to decrease for those areas, particularly during spring and summer, which combined with increased temperatures (and therefore greater evapotranspiration/uptake of water by plants) is likely to result in more frequent and severe droughts." http://www.voxy.co.nz/national/5/364094 Supermoon 2020: Eastern regions have best chance to see Flower Moon May 06 2020 , Danielle Clent12:34, JOSH KIRKLEY An astrophotographer captured the super snow moon rise over Auckland on February 9. Trustworthy, accurate and reliable news stories are more important now than ever. Support our newsrooms by making a contribution. It's an "east-west" split for where best to see the last supermoon of the year, MetService says. On Thursday, a supermoon - known as the 'Flower Moon' - will rise in the sky for the last time in 2020. Auckland astrophotographer and Stardome educator Josh Kirkley said it will appear just as bright and large as the 'Pink Moon' did in April. "The name 'Flower Moon' comes from the northern hemisphere where the full moon in May is as-sociated with flowers blooming as they go into spring," Kirkley said.
LACHIE KIRK/SUPPLIED Fifteen-year-old Lachie Kirk captured this picture of a supermoon in Hawke's Bay. It will be best viewed as it rises in the east about 5.30pm. This is the same time the sun is about to set in the west. "It will remain in the sky for the entire night before setting in the west when the sun rises again on Friday mōrena," Kirkley said. Having a high vantage point with unobstructed views of the horizon will give the best chance of seeing it as it rises, he said. But MetService meteorologist Andy Best said some bad weather in western parts of both the North Island and the South Island may hinder some people's viewing. "Most places in the west from about Manawatū northward are going to see cloudy periods with isolated showers," Best said. Places such as Bay of Plenty, Gisborne, Hawke's Bay, Wairarapa, Kāpiti and Wellington in the North Island should be "good viewing areas". Auckland and Northland are expected to also be cloudy with isolated showers. In the South Island, most eastern places like Nelson, Marlborough, Canterbury, Otago should have clear skies. Southern Lakes, Dunedin, Southland and Clutha are expected to be partly cloudy as a front ap-proaches, Best said. The West Coast of the South Island will also be cloudy with showers. "It's an east-west split, basically." For stargazers in parts of the country that will have prime viewing, Kirkley said people with a de-cent DSLR and a zoom lens between 200 millimetres and 600mm should get some nice close-ups.
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"Setting up a timelapse as it rises always looks really great," he said. "No telescopes are needed for a supermoon." https://www.stuff.co.nz/national/121422685/supermoon-2020-eastern-regions-have-best-chance-to-see-flower-moon Effects of Hawke's Bay drought revealed in Nasa photographs 10 May, 2020 12:27pm
A photo taken in May 2019, left, compared with late April 2020 in Hawke's Bay shows the stresses on the region's landscape caused by drought. Photos / NASA Hawkes Bay Today By: Christian Fuller The photos, taken by National Aeronautics and Space Administration (Nasa), compare the region on May 2, 2019, and April 29 this year. Hawke's Bay's landscape is noticeably greener in last year's photo. Only a quarter of its expected rain fell in the region over the past six months. December through February is typically the driest period in north and central New Zealand, but ac-cording to Nasa, the 2019-2020 summer season was especially dry, leaving the entirety of North Is-land in severe meteorological drought. According to the National Institute of Water and Atmospheric Research (Niwa), drought in some parts of the New Zealand this year rivals that of 2013, New Zealand's worst drought in decades. Niwa reported five days ago that Hastings has been in continuous drought for 29 days, according to the New Zealand drought index. In 2013 the district was in drought for 33 continuous days. Waikato had drought for 61 continuous days, just two short of the 2013 streak, and Auckland topped records with 77 days of continuous drought. The lack of rain in Auckland has left reservoirs at about 46 per cent of capacity, compared with the average 76 per cent for the time of year. The drought's impact on plants and trees is visible in the images, acquired with the Moderate Reso-lution Imaging Spectrometer (Modis) on Nasa's Aqua satellite. Central Hawke's Bay Mayor Alex Walker said the drought was a challenge to all farmers and would take a least a year to recover from. https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12330834 Hawke's Bay's unwelcome frosts add to drought woes 22 May, By: Shannon Johnstone Farmers battling drought across Hawke's Bay say the bracing cold in the mornings, where tempera-tures have been below zero, is the last thing they need right now. Frost blanketed Hawke's Bay again on Friday morning, with another forecast for Saturday morning. The Takapau Plains were again the coldest at –3.1C.
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This early Hawkes Bay lamb spent lat night inside due to the cold. Photo /Sarah Gray. The frost is not good news for farmers who are still very much in drought, Federated Farmers Hawke's Bay President Jim Galloway said. Galloway said the frost drops soil temperature which slows grass growth, the one thing farmers need right now. https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12333968 Auckland’s drought most extreme in modern times 22 May 2020 This is one of the most extreme drought events for Auckland in modern times and similar to one ex-perienced in 1993/94. Just 126mm of rain was recorded at NIWA’s Mangere weather station between 1 January and 21 May – that is 31% of normal. The normal period is 1981-2010 for January-May. NIWA data shows this is one of the most severe droughts since the early 20th Century. The origins of the drought began about 8000km away in the Indian Ocean late last year with a phe-nomenon known as the Indian Ocean Dipole (IOD). The IOD is an atmospheric seesaw that impacts sea surface temperatures, rainfall, and wind. As weather systems tracked toward New Zealand from the west and north, they lacked moisture be-cause of cooler eastern Indian Ocean seas caused by the IOD. In late 2019 and early 2020, a lack of atmospheric rivers, or plumes of moisture that extend to the mid-latitudes from the tropics, has limited heavy rainfall events. This was a factor that was promi-nent in New Zealand during early 2017 that led to several extreme rainfall events. As New Zealand headed into summer the IOD persisted and had some help from the tropical Pacific. Although the El Niño Southern Oscillation was neutral, there was a lean toward an atypical form of El Niño called Modoki. In this form of El Niño, ocean temperature anomalies are larger in the cen-tral tropical Pacific than the east, which has flow-on impacts on circulation patterns around the globe. This pattern has been present for the better part of the last two years. There are indications that Modoki events are increasing as part of the climate change signal. Tropical cyclone activity between November 2019-April 2020 was near normal for the SW Pacific and New Zealand saw two ex-tropical cyclones (Uesi, Gretel) miss the driest areas. The Southern Annular Mode or SAM began a two month run of positive values during February – a positive SAM is associated with more tranquil weather in the New Zealand region. Reduced rainfall and thunderstorm activity in the Coral Sea means that low pressure systems ap-proaching from the west have not been able to tap into sub-tropical moisture, leading to less rain for New Zealand. NIWA’s climate change expectations suggest spring average rainfall decreases for northern New Zealand, including Auckland. When this is combined with increased temperatures (and therefore greater requirements of water by plants) it is likely to result in more visible regional impacts from water shortages and drought. Two significant climate features may develop in the next 3-6 months: a negative IOD and La Niña.
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These two features could give northern and eastern New Zealand better odds for seasonal rainfall, but not right away. New Zealand might begin experiencing these effects during the 2nd half of winter or early spring. In the meantime, longer than normal dry spells will remain possible during the month of June. https://niwa.co.nz/news/aucklands-drought-most-extreme-in-modern-times ICNZ releases total weather-related losses for 2019 28 May 2020 by Ksenia Stepanova Insurers paid out $167.6 million in weather-related losses over 2019, according to new figures re-leased by the Insurance Council of New Zealand (ICNZ). Provisional results in March showed over $118.8 million spent by insurers on severe weather events, making 2019 the sixth most expensive year since 2010. The latest figures were released after the finalisation of claims for the November Timaru hailstorm, which increased from $83 million to $130.75 million, and the November tornado in Christchurch, which hit $4.04 million. ICNZ says the Timaru hailstorm has been “the second most costly weather event of the century,” with chief executive Tim G by Ksenia Stepanova rafton highlighting the vital role of insurance in protecting against natural disaster and weather events.
Insurers paid out $167.6 million in weather-related losses over 2019, according to new figures released by the Insurance Council of New Zealand (ICNZ). Provisional results in March showed over $118.8 million spent by insurers on severe weather events, making 2019 the sixth most expensive year since 2010. The latest figures were released after the finalisation of claims for the November Timaru hailstorm, which increased from $83 million to $130.75 million, and the November tornado in Christchurch, which hit $4.04 million. ICNZ says the Timaru hailstorm has been “the second most costly weather event of the century,” with chief executive Tim G by Ksenia Stepanova rafton highlighting the vital role of insurance in protecting against natural disaster and weather events. “The figures reflect the true cost of weather events and the vital role insurance plays in supporting communities,” Grafton said. “While the Timaru hailstorm lasted minutes, the destructive nature of the event was felt by thou-sands of locals. Insurance support for people equates to more than $2,700 for every man, woman and child that live in the city.” “The very nature and impact of the hailstorm shows why it is so important that Kiwis have the sup-port insurance provides to help get them back on their feet when the unforeseen happens,” he added. 2019’s total insured losses are as follows: Tasman District fires, 5-23 Feb - $3.9 m West Coast wind, 26-27 March - $4.09 m Taranaki and Auckland Storms, 10-13 August - $7.8 m Christchurch Tornado, 18 November - $4.04 m Timaru hailstorm, 20 November - $130.7 m National storm including Southern Lakes flooding, 3-18 Dec - $17 m. https://www.insurancebusinessmag.com/nz/news/breaking-news/icnz-releases-total-weatherrelated-losses-for-2019-223522.aspx
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Queen’s Birthday Weekend Thursday, 28 May 2020 Press Release: MetService MetService is forecasting unsettled weather for this long weekend and a warm start to winter on the 1st of June. An area of low pressure from the north Tasman Sea is forecast to move southeastwards across the North Island this long weekend, bringing periods of rain or showers to northern and central New Zealand. Meanwhile, a ridge of high pressure remains anchored over southern New Zealand, bring-ing settled weather there. MetService Meteorologist Peter Little commented, “A useful 20 to 40mm of rain fell across southern parts of Northland and northern parts of Auckland during Wednesday, but much more rain is need-ed to make a difference in these and other dry regions.
Meteorological winter starts on Monday, being the first day of June, though not that many people may notice. Little explained, “The predominant northerly wind flow means temperatures will be warmer than average for the next week, and when combined with cloud cover it will keep many North Island places in double digits overnight. However, over southern New Zealand, morning frosts and some persistent areas of fog are likely due to clear skies and light winds associated with high pressure”. https://info.scoop.co.nz/MetService Vehicles trapped as thunderstorms cause flooding in North Island, heavy rain warnings today 31 May, 2020, [email protected] Parts of the Coromandel have received a colossal 170mm of rain overnight, as the start of a low pres-sure system hits the North Island. At least two vehicles were trapped in floodwaters last night as torrential rain and thunderstorms lashed the Coromandel Peninsula. The first thunderstorms hit the holiday hotspot around midnight, bringing 100mm of rain As of 9am there had been 171mm of rain in Whitianga, 167mm in Whenuakite and 113mm in Whangamatā, according to Niwa.
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Flooding close to Dalmeny Corner in Whenuakite, off SH25, on the Coromandel Peninsula following torrential rain overnight. Supplied photo / Georgie Hood A large high-pressure system expanding east of New Zealand was working with a weak low to both produce rain and stop it from moving. https://www.nzherald.co.nz/nz/news/article.cfm?c_id=1&objectid=12336066
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