U.S. FLASH FLOOD WARNING DISSEMINATION VIA RADIO

AND TELEVISIONBob Henson

UCAR CommunicationsUniversity Corporation for Atmospheric Research

Boulder, CO

Thanks to: Paul Polger (NWS Headquarters)

Bob Glancy (NWS/Denver)Andrea Johnson (UCAR Communications)

Warnings make a difference!

U.S. began watch/warning system in 1950s. Since then, weather-related deaths have dropped by roughly 50%

However, flood deaths have not shown such a drop.

U.S. deaths from major weather hazards, 1940-1998Data courtesy National Weather Service

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Deadliest Weather Hazard by Year, 1940 - 1998

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How important are radio & TV?

TV is cited most often in surveys as the primary news source of U.S. residents.

Radio is where most people say they expect to hear about news first.

Even with Internet, radio remains important as portable news source.

Do the media take floods seriously?

1988 study of time needed to broadcast warnings on Oklahoma City TV stations showed big differences among weather hazards. Tornadoes: 5-6 min. Severe thunderstorms: 5-10 min. Flash floods: 23-47 min.

Do the media take floods seriously?

The Weather Channel is received by over 72 million in U.S.. Ratings higher than CNN for major weather threats

TWC has on-air experts for hurricanes, severe thunderstorms/tornadoes, and winter storms—but no flood expert!

Do the media take floods seriously?

Not always! From TV Guide (largest circulation magazine in America), 23/10/99

Why might media downplay floods?

Hard to convey an entire flood in one image

Why might media downplay floods?

Flash floods can be very localizedFloods occur with other weather

hazards that can be distractingFloods aren’t as dramatic as

howling winds

Flood deaths in vehicles, 1985 - 1997

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Vehicular risk from U.S. floods is increasing

More vehicle miles traveled per year (at right: millions/yr)

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1969 1977 1983 1990

Vehicular risk from U.S. floods is increasing

More light trucks being sold, primarily sport utility vehicles— perceived as safer than cars in bad weather.

Light truck sales in U.S. (thousands)1992—4,446 1995—6,0701993—5,486 1996—6,3891994—5,869 1997—6,707

(1997 represents a 66% increase in sales over 1992)

U.S. radio has changed

Less government control over content w/deregulation (70s/80s)

Most stations used to have hourly newscasts; now, most do not.

Weather reports are much shorter, often less than 30 seconds long.

Emergency Broadcast System

It’s now the Emergency Alert System, changed to incorporate new technology and serve cable TV systems (those with 20K+ subscribers)

The weather component remains voluntary! Lead stations (1 or 2 per region) agree through

statewide plans to broadcast warnings (usually tornado and flash flood); others may follow

However, no station is legally obligated to broadcast any single warning.

Will new technology help?

Targeted warnings through NOAA Weather Radio (SAME system)

New technology for sending localized weather information by cell phone/pager

BUT: What about poorer, more vulnerable citizens? Especially for them, radio will remain a vital means of communicating weather hazards.

Education of motorists: more crucial than ever

Not every radio station will warn you!

Two feet of water can carry away your car/truck/SUV

Leave car for higher ground if flooding is imminent

UPDATE: HYDROMETEOROLOGICAL

ASPECTS OF THE MESOSCALE ALPINE PROJECT (MAP)

Bob HensonUCAR Communications

University Corporation for Atmospheric ResearchBoulder, CO

What is MAP all about? 10-year international research effort

culminating in field project in and near Alps, fall 1999

Two main field components:Dry-MAP: gravity wave breaking, gap

flow, potential vorticity (PV) generation near Alps

Wet-MAP: how mountains enhance heavy rainfall and flooding through microphysical, dynamical, and hydrological elements.

Key observation tools

Existing operational network (6,000 rain gages, radiosondes, 20 overlapping radars)

Special facilities for MAPEight aircraft (U.K, France, Germany, Italy,

Switzerland, U.S.), including two with Doppler radarResearch radar (NCAR, Meteo-France, Doppler on

Wheels)

Proposed triple ground radar array for dual-Doppler and microphysics observations in the Ticino area. The color background plotindicates elevation in kilometers above MSL. The yellow outlinesindicate regions of low-resolution dual-Doppler coverage between theSMI radar at Monte Lema and the RONSARD at Casaleggio. The whiteoutlines indicate regions of high-resolution dual-Doppler coverageobtained between the S-Pol at Vergiate and the other two radars (theselocations are still tentative)

The generic flight track design to obtain thermodynamic,high-resolution Doppler radar, and microphysical data (Electra or P-3aircraft, solid line). The generic flight track design to obtain boundarylayer height, moisture and wind (Fokker, broken line)