Process of Issuing Forecasts and Warnings NWS Office

Process of Issuing Forecasts and Warnings

NWS Office Locations Salt Lake City WFO

The Datasets We Use

Observation Tools - Ground Level Automated Surface Observation System (ASOS) • • • Rainfall Temperature/Dewpoint Weather Wind Sky Cover Freezing Rain Thunderstorm Visibility Pressure

Mesonets • Cooperative projects between researchers at Universities, National Weather Service, Land Management Agencies, Departments of Transportation, and private/commercial firms • Provides access to current weather observations • Observing networks are managed by federal, state, and local agencies and private firms • Weather observations of temperature, relative humidity, wind speed and direction, precipitation, and other weather parameters are available at thousands of locations • Used operationally by National Weather Service forecasters and used extensively by researchers

Doppler Radar Network

Observation Tools – Upper-air Radiosonde • Network of 92 Radiosonde stations in North America and the Pacific islands and 10 stations in the Caribbean • 6 feet diameter balloon…expands to 20 feet as it rises to over 100, 000 feet in the atmosphere • Radiosonde sensors measure pressure, temperature, dewpoint, and wind • Radio transmitter sends measurements to a ground receiver

Satellite Network Composed of Polar Orbiting and Geostationary Satellites • Monitoring and forecasting of weather, water, and climate • Search and rescue applications GOES M Launch

River Gage Networks

Marine Buoys

Numerical Weather Prediction

AWIPS

The Forecast Process Forecasters analyze / interpret varied datasets to develop a 4 -dimensional picture of the atmosphere • • • Observations Analysis Diagnosis Prognosis Communication

What We Produce

Zion National Park Convective Warnings • Tornado Warnings • Severe Thunderstorm Warnings • Flash Flood Warnings • Salt Lake City Tornado – 8/11/99

Nonconvective Watches, Warnings, and Advisories Heavy Snow, Wind Chill, High Wind, Dense Fog

Public Forecast Products Text, Digital, and Graphical Zone Forecasts Tabular State Forecast For Utah Area Forecast Discussion Flash Flood Potential Rating Air Stagnation Index Coded Cities Forecast Mountain Weather Point Forecast Matrices Hazardous Weather Outlooks, Short Term Forecasts, and Special Weather Statements

Fire Weather Forecasts • Fire Weather Planning Forecast for Utah • Red Flag Watches and Warnings • Spot Forecasts • Trend Forecasts • Smoke Management Forecasts

Aviation Forecasts • 8 Terminal Aerodrome Forecasts (TAFs) – ENV, LGU, OGD, SLC, PVU, CDC, BCE, SGU) • 9 Transcribed Weather Broadcasts (TWEBS), plus a Synopsis • Aviation Weather Warnings (AWWs)

River Forecasts and Warnings • Flood Warnings for 23 Forecast Points • Areal Flood Warnings

Climate • WFO SLC Climate Products – Daily Climate Report – Monthly Climate Summary for Salt Lake City/Utah – Preliminary Climatology Data (F 6) – Record Event Report – Storm Data reports

Marine

Forecast and Warning Dissemination NOAA Weather Radio All Hazards Emergency Alert System (EAS) Media Internet – Really Simple Syndication (RSS) feeds Public NWR EAS Amateur Radio A. R. E. S. WFO SLC Media Family of Services NWR EAS Internet County Officials NAWAS EMWIN Pager - EWARN State circuits

Watch/Warning Decision Making • • Office-based criteria (customer-driven? ) Time of day or season (impact driven) Likelihood of occurrence (forecaster confidence) Magnitude of event Potential impact Local knowledge Collaboration

Dissemination Considerations • Product Wording – Use of uncertainty? – Potential impact • Timing (e. g. news casts) • Single voice (both internal and external)

Challenges and Frustrations • • • Being wrong Lack of verification Misinterpretation of forecasts Local variations in observed weather information not “fitting” forecast, though forecast as a whole was excellent Maintaining high level of performance/productivity, despite shiftwork environment Collaboration (internal and external) Different forecasts from different sources Software issues Time constraints

WFO Roles • • Public Service (4 -5) Forecasters (8 -12) Service Hydrologist Warning Coordination Meteorologist Science and Operations Officer Technical Support (3 -4) Admin Assistant Meteorologist-in-Charge