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National Digital Forecast Database (NDFD) Convective Outlook Hazard Probability Elements
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The National Digital Forecast Database (NDFD) contains a seamless mosaic of digital weather forecasts from National Weather Service (NWS) field offices and the National Centers for Environmental Prediction (NCEP). The Storm Prediction Center (SPC) is the NWS' center of expertise for forecasting convection, especially for life-threatening and economically-disruptive weather events such as tornadoes, large hail, and damaging winds. As of April 30, 2009, the following Convective Outlook Hazard Probability elements prepared by the SPC are now available in the NDFD in operational status: • Categorical Convective Outlook for today (Day 1), tomorrow (Day 2), and the day following (Day 3) • Probability of Tornadoes (Day 1) • Probability of Hail (Day 1) • Probability of Damaging Thunderstorm Winds (Day 1) • Probability of Extreme Tornadoes (Day 1) • Probability of Extreme Hail (Day 1) • Probability of Extreme Thunderstorm Winds (Day 1) • Total Probability of Severe Thunderstorms (Day 2 and Day 3) • Total Probability of Extreme Severe Thunderstorms (Day 2 and Day 3) All of these elements are currently only available for the contiguous U.S. (CONUS) and the 16 pre-defined NDFD CONUS subsectors. The Categorical Convective Outlook elements specify the perceived level of threat via the descriptive wording: Slight, Moderate, and High Risk. However, these outlooks, do not display the forecaster's expectations of the individual severe weather hazards (large hail, damaging winds, and tornadoes). The individual probabilistic elements further express forecaster uncertainty of the individual severe weather hazards through the use of probabilities (i.e., percent likelihood of occurrence).
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0000-00-00 Comment End Date: 0000-00-00
David B. Caldwell
Transition to Operational
Last edit date to this meta-data: 2019-07-05