Understanding Violent Weather Fundamentals of Forecasting

1. Understanding Violent WeatherFundamentals of Forecasting Lynn P. Maximuk Meteorologist In Charge WFO Pleasant Hill, MO October 24, 2005 NWS Digital Services

2. IT Has Changed The Weather Forecast World • The NWS primary product is information – not text messages • Partners and customers demand more of the most current information possible, available when they want it • High resolution graphical and tabular data for improved service NWS Digital Services

3. Digital Forecast Goals • Leverage national and local expertise to: • Provide high resolution forecast information • Ensure meteorological consistency • Focus on high impact events • Provide Information in multiple formats NWS Digital Services

4. National Digital Forecast Database (NDFD) • Multiple input sources – Time and Space • WFOs • National Centers HPC/SPC/CPC/AWC/NHC/TPC etc. • NWS product – not local office product • Offices produce a piece of the product • Meteorological consistency a must • One stop shopping NWS Digital Services

5. Digital Data • Will continue to evolve • Add a vertical dimension • Watch and warning information • Observational information • Climatological information • Tap into GIS capabilities • Readily useable formats NWS Digital Services

6. Modern Technology • New ways to prepare forecasts by depicting the underlying forecast information • Flexibility extracting information to meet partner and customer needs – formats without bounds • Ability for rapid updates NWS Digital Services

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8. Service and Information Flow • Frequent updates in short term – hourly • High spatial resolution – 5km nationally and 2.5km locally • More detailed forecast information for weather parameters important to partners and customers to feed their formatters and decision software NWS Digital Services

9. How to Obtain NDFD Data • Data, decoders and detailed information available at the following web sites: • Weather.gov/ndfd • Weather.gov/ndfd/technical.htm • Database contents, format, etc. • Available in GRIB2, NetCDF and XML NWS Digital Services

10. Data Extraction Ideas The Sky is the Limit! NWS Digital Services

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12. Traditional Forecast Format NWS Digital Services

13. Detailed Forecast Information NWS Digital Services

14. Decision Aid NWS Digital Services

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16. Polygon Warning Experiment • Warnings were issued for the ‘threat area’ of a storm, counties fell out as needed from this threat area. • Extensive outreach on key issues conducted spring 2005. • Multiple warnings in effect for a county. • Impact on EAS • How to ‘visualize’ the polygons? NWS Digital Services

17. Polygon Warning Experiment • Customer feedback: • Many emergency managers expressed that one of the reasons they rated services improved this year was because of the refined ‘box’ used in warnings. • Some radio stations lukewarm (especially with regard to tornado warnings and EAS), as they get more warnings for the same ‘county’. NWS Digital Services

18. Media perspective on polygons • Cones Of “StormTracks” are already familiar with viewers • Text Crawls already cut whole county warnings • Challenge is to marry audio message with new video display • Learning curve with Media and NWS NWS Digital Services

19. Polygons in action NWS Digital Services