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Storm Prediction Center (SPC)
The Storm Prediction Center is a branch of the NWS and provides data to the public about severe weather as well as other hazardous weather.
Severe Weather
The SPC issues probability maps for days 1 through 8, but in different forms. The day 1 always provides the probability of tornadoes, wind, hail, and the risk of severe weather. Days 2 and 3 only provide the risk and probabilistic outlook for any severe weather type. Days 4 through I provide only the probability of severe weather in general.
Risk Classifications of Severe Weather
Severe weather is classified by the SPC in 6 ways:
- General thunderstorms
- Marginal risk
- Slight risk
- Enhanced risk
- Moderate risk
- High risk
