APWA 2016 PWX 8/28/2016

1

NWS Resources For Public Works

August 28th, 2016Shawn DeVinnyshawn.devinny@noaa.govMeteorologistNational Weather Service Twin Cities/Chanhassen, MN

APWA 2016 PWX 8/28/2016

2

National Weather ServiceDepartment of Commerce (DOC)

National Oceanic & Atmospheric Administration (NOAA)

Fisheries ResearchNational Weather

Service (NWS)

Weather Forecast Offices (WFOs)

River Forecast Centers (RFCs)

Center Weather Service Units

(CWSUs)

Satellites & Information

Ocean Service

Marine & Aviation

Operations

122 Weather Forecast Offices

APWA 2016 PWX 8/28/2016

3

The protection of life and property and the enhancement of the national economy

Accomplishing The Mission

▪ Forecasting▪ Observing▪ Analyzing▪ Communication▫ Warnings▫ Watches▫ Various Text Products▫ NOAA Weather Radio▫ Website(s)▫ Social Media

APWA 2016 PWX 8/28/2016

4

Building A Weather-Ready Nation

▪ First goal: Improve Weather Decision Services for Events that Threaten Lives and Livelihoods

▪ User engagement: “Increase engagement with users and core partners…”

Times Are Changing In The National Weather Service

▪ Scientific understanding and weather model accuracy has improved over the years

▪ In some well forecast high-impact weather events, communication was found to be a shortcoming when the public was underprepared, despite a good forecast

APWA 2016 PWX 8/28/2016

5

Weather-Ready Nation

▪ Shift from product-focused service to interpretation and consultation

▪ NWS will evolve from the forecaster generating products based on static definitions toward a services model

Products And Services Available To Public Works

▪ Call Us! Please! (952-361-6671 Twin Cities Office)▫ We answer the phone 24 hours a day. Remember, we are a 24/7/365 operation! Don’t ever worry about “bugging” us, this is why we’re here▪ Social Media- Facebook/Twitter▪ Utilize NWSChat

APWA 2016 PWX 8/28/2016

6

Products And Services Available To Public Works

▪Finding Weather Data▪Snowfall Data▪Temperature Data▪Event Summaries

▪Historical Weather Information▪Top News Archives On Our Website▪The MN State Climatologist

Products And Services Available To Public Works

▪Warnings/Advisories/Watches▫ How are they defined?▫ Pros/Cons▫ Statistics

APWA 2016 PWX 8/28/2016

7

Watch, Warning, Advisory

▪WATCH: Weather having a significant impact on society is possible but details are uncertain.

Watch, Warning, Advisory

▪WARNING: Weather having a SIGNIFICANT impact on society is imminent or highly likely. Dangerous conditions expected.

APWA 2016 PWX 8/28/2016

8

Watch, Warning, Advisory

▪ADVISORY: Weather having a MODERATE impact on society is imminent or highly likely. Hazardous conditions expected, but should not be dangerous if precautions are taken.

NWS Warning Criteria (discretion)

▪Ice Storm: ¼” ice or more▪Wind Chill: -35▪High Wind: 40 mph sustained, 58 mph gusts ▪Heat: 105 heat index▪Flood: river reaches flood stage or long-term areal▪Flash Flood: life threatening▪Severe Tstm: 58 mph and/or 1” hail▪Tornado: radar or spotter

APWA 2016 PWX 8/28/2016

9

NWS Products

▪Winter Storm Warning▫ Snow of 6” or more in 12 hours ▫ Or Snow of 8” or more in 24 hours▫ Or ½” or more of sleet▫ Or a combination of heavy snow, sleet, significant wind, or freezing rain

NWS Products

▪Winter Storm Watch/Blizzard Watch▪Watches are issued once the forecaster reaches 50% confidence in an event reaching the criteria.▪We continue to move to forecaster discretion based on impacts▪The process is evolving… “NWS will evolve from static definitions toward a services model”

APWA 2016 PWX 8/28/2016

10

Pros Of Watch Products

▪Pros▫ Provides you with a “heads up” 36+ hours ahead of time▫ Well communicated▫ Area and time defined

Cons Of Watch Products

▪Cons▫ Can be misinterpreted▫ Watches = 50% of criteria being reached. What does this mean to the user?▫ In theory, up to 50% of watches will NOT be converted to a Warning▫ Many expect a Watch to become a Warning. This is a misinterpretation of the product

APWA 2016 PWX 8/28/2016

11

January 30th, 2014

▪Heavy snow occurred across the metro from 6AM-9AM on a Thursday morning.

▪Amounts were generally under 6”, but a Winter Storm Warning was issued the night before due to expected societal impacts from the timing and intensity of the snow.

January 30th, 2014

APWA 2016 PWX 8/28/2016

12

January 30th, 2014

AFD Update

APWA 2016 PWX 8/28/2016

13

NWS Products

▪Winter Weather Advisory▪Snow of 3-6”▪Blowing Snow causing significant visibility restrictions▪Sleet of less than ½”▪Exceptions to these guidelines exist based on forecaster judgment▫ Impacts

NWS Products

▪Blizzard Warning▫35+ mph (sustained or frequent gusts)▫Visibility frequently < ¼ mile

▪What’s Missing?▫Considerable falling OR blowing snow

APWA 2016 PWX 8/28/2016

14

Ground Blizzards

▪Major Misconception!

▪It’s all about Visibility

APWA 2016 PWX 8/28/2016

15

Pros Of Warning Products

▪Pros▫ Clearly defines an area and time when impacts will occur▫ Clearly defines the hazard▫ Communication of these productsWell advertised- easy for you to get this information ▫ Consistency▫ Credibility

Cons Of Warning Products

▪Cons▫ County based- we are limited to county borders▫ Difficult to get away from issuing based on static definitions ▫ Often lacks a description of forecaster confidence▫ Can be difficult to interpret large blocks of text

APWA 2016 PWX 8/28/2016

16

Winter Storm Warning Stats

▪POD- Probability Of Detection (county-by-county analysis)▫92% accuracy▪Average Lead Time For You To Prepare▫21.2 hours

Products And Services Available To Public Works

▪Additional Useful Resources▫Mobile Devices▫Hourly Weather Graph▫AFD- Area Forecast Discussion▫Graphical Forecasts

APWA 2016 PWX 8/28/2016

17

Mobile Devices – NWS Info

mobile.weather.gov

http://innovation.srh.noaa.gov/NWSwidget

Useful Resources

▪The Hourly Weather Graph/Table▪An interactive graph showing hourly details for weather elements for any location▪A great tool in aiding decision-making▪When will the snow be the heaviest?

APWA 2016 PWX 8/28/2016

18

The Hourly Weather Graph

How To Get To The Hourly Weather Graph

1) Go to our national website: weather.gov

Useful Resources

APWA 2016 PWX 8/28/2016

19

How To Get To The Hourly Weather Graph

2) Submit you local city or zip code in the box in the upper left hand corner

Useful Resources

How To Get To The Hourly Weather Graph

3) Your local forecast comes up, find the

“hourly weather graph” on the right hand side

Useful Resources

APWA 2016 PWX 8/28/2016

20

The Hourly Weather Graph

▪What if this forecast was for your location?

A Table Instead Of a Graph?

APWA 2016 PWX 8/28/2016

21

Area Forecast Discussion

▪This product explains the thinking behind the forecast and is generated by the forecaster after they’ve completed their forecast

▪The AFD is updated at least 2x per day

▪Typically updated ~4 AM and ~4PM

▪Will include scientific terminology

How is this product useful to Public Works?

▪Portraying confidence▫ To get a sense of high or low forecaster confidence may influence decision-making▫ If confidence is low, an explanation to why will be offered. Is it a timing issue? Uncertainty concerning precipitation type?▪Can explain details you simply can’t get from the local forecast

APWA 2016 PWX 8/28/2016

22

An AFD Example

Area Forecast Discussion

▪Go to our local website: weather.gov/twincities

▪Hover over “Forecasts” on the top center, and click on “Forecast Discussion”

APWA 2016 PWX 8/28/2016

23

Weather Graphics

▪We produce a “Weather Story” updated every evening and early morning

▪Instead of (or in addition to) reading various text products, you may find these very beneficial ahead of a winter storm

▪You can find the weather story on our home page and we also post all updates to our Facebook and Twitter accounts

Weather Graphics During Winter Weather

▪Before The Storm▫ Timing

APWA 2016 PWX 8/28/2016

24

Weather Graphics During Winter Weather

▪Before The Storm▫ Timing▫ Uncertainty

APWA 2016 PWX 8/28/2016

25

Weather Graphics During Winter Weather

▪Before The Storm▫ Timing▫ Uncertainty▫ Communicating how mixed precipitation events will unfold▫ Graphics best demonstrate where to expect snow, sleet, freezing rain, rain…etc.

APWA 2016 PWX 8/28/2016

26

APWA 2016 PWX 8/28/2016

27

Radar Basics

▪The difference between rain and snow▪Be careful when viewing radar that displays snow, rain, and mix▫ Radar doesn’t actually detect precipitation type directly▫ Algorithms convert the reflectivity to a precipitation type (not always accurate)

Radar Basics

▪Snow banding▫ A band of snow is usually prominent during most snow storms. There is often a narrow band of heaviest reflectivity within this. This heavy narrow band will pivot at some point, which typically produces the highest snowfall amount

APWA 2016 PWX 8/28/2016

28

Rain vs. Snow

Rain Snow

Base vs Composite Reflectivity

Base Reflectivity▪The lowest radar scan▪Helpful in seeing as low to the ground as possible▪Won’t fool you as easily because you are seeing the lowest scan

Composite Reflectivity▪Displays the maximum return at any level▪Will always look worse than base reflectivity▪Can fool you in to thinking it should be snowing (evaporation is common at the onset of a storm)

Recommendation: Use base reflectivity only

APWA 2016 PWX 8/28/2016

29

Products And Services Available To Public Works

Finding Past Weather Data▪Snowfall Data▪Temperature Data▪Event Summaries

Historical Weather Information▪Top News Archives On Our Website▪The MN State Climatologist

MN State Climatologist

▪Another resource for climatological weather data▫ Includes climate data for the Twin Cities back to the 1800’s

▪http://climate.umn.edu/

APWA 2016 PWX 8/28/2016

30

Finding Past Weather Data

▪Hover over “Climate and Past Weather,” then click on “Local”

APWA 2016 PWX 8/28/2016

31

Monthly Climate Data (An Example)

▪Look back at how much snow fell

APWA 2016 PWX 8/28/2016

32

APWA 2016 PWX 8/28/2016

33

Event Summaries

▪After a winter weather event, we’ll post a summary▫ Table of snowfall amounts▫ Map of snowfall amounts▪Check our website for these▫ “Top News of the Day”▪Typically posted to social media as well▪Need snowfall amounts during the storm? Check the “Public Information” statement

APWA 2016 PWX 8/28/2016

34

Send us reports to!

Products And Services Available To Public Works

▪ Call Us! Please! (952-361-6671 Twin Cities Office)▫ We answer the phone 24 hours a day. Remember, we are a 24/7/365 operation! Don’t ever worry about “bugging” us, this is why we’re here▪iNWS- Interactive NWS ▪Social Media- Facebook/Twitter▪ Utilize NWSChat

APWA 2016 PWX 8/28/2016

35

Warning Reception: iNWS

▪Interactive National Weather Service▫ Weather alerts to your mobile device via text message and email▫ Select your alert area and which alerts you want▫ Public safety officials

http://inws.wrh.noaa.gov

Find us on Facebook

APWA 2016 PWX 8/28/2016

36

Follow Us on Twitter

NWS Chat

▪You can sign up for NWS Chat▫Must first request access via the website▫https://nwschat.weather.gov/live/▪Our office identifier is “MPX”▫Join the “MPX Chat” room or find your local office▪Chat rooms are monitored 24/7▪We respond to questions and often post more and quicker updates concerning the weather▪You can also see a feed of our products as they are published

APWA 2016 PWX 8/28/2016

37

Shawn DeVinnyshawn.devinny@noaa.govMeteorologistNational Weather Service Twin Cities/Chanhassen, MN

A special thanks to…Mark Ray

Public Works Director/City EngineerCity of Crystal, MN

Thank You!