The Storm Prediction Center (SPC) is the national hub for forecasting severe convective weather in the United States. It operates under the National Centers for Environmental Prediction and is based in Norman, Oklahoma. The SPC's primary responsibility is to assess the risk of tornadoes, damaging winds, and large hail across broad areas and to alert emergency managers, the public, and local weather offices.
Mission and role
SPC's mission combines real-time forecasting with research and training. Forecasters analyze observations, radar and satellite imagery, and numerical model guidance to produce probabilistic outlooks and short-term products. The center coordinates with local National Weather Service offices, the research community, and other federal partners to translate its assessments into watches and guidance that support public safety decisions.
Key products
- Convective outlooks: Day 1–3 assessments that categorize risk levels (marginal, slight, enhanced, moderate, high) and give probabilities for severe events.
- Mesoscale discussions: Short-term analyses that describe evolving areas of concern and the reasoning behind potential watch issuance.
- Watch products: Tornado and severe thunderstorm watches that indicate conditions are favorable for organized severe storms over a region for a specified time.
SPC products often include probabilistic metrics (percent area within which events are expected) and special markings for potential "significant" severe events. These tools help emergency managers balance precautionary actions with the uncertainties inherent in convective forecasting.
The center evolved from earlier severe-weather forecasting efforts and benefits from proximity to academic and research institutions in Norman. Its operational-concept emphasis on probabilistic messaging and coordination with local forecast offices distinguishes watch issuance from local warnings: a watch means conditions are favorable for severe weather; warnings are issued locally when severe weather is imminent or occurring.
Beyond operations, SPC contributes to applied research, training for forecasters, and post-event analysis that improves future predictions and public response to severe weather threats.