KD4PYR NWS/NOAA Forecast Images

NWS/NOAA Forecast Images

SPC Day 1 Categorical Outlook

Severe Thunderstorm Risk Categories

Category	Definition	Possible Impacts
THUNDERSTORMS (no label)(light green)	No severe* thunderstorms expected. Lightning/flooding threats exist with all thunderstorms.	Winds to 40 mph. Small hail.
1 - MARGINAL (MRGL)(dark green)	Isolated severe thunderstorms possible. Limited in duration and/or coverage and/or intensity.	Winds 40-60 mph. Hail up to 1". Low tornado risk.
2 - SLIGHT (SLGT)(yellow)	Scattered severe storms possible. Short-lived and/or not widespread, isolated intense storms possible.	One or two tornadoes. Reports of strong winds/wind damage. Hail ~1", isolated 2".
3 - ENHANCED (ENH)(orange)	Numerous severe storms possible. More persistent and/or widespread, a few intense.	Several reports of wind damage. A few tornadoes. Damaging hail, 1- 2".
4 - MODERATE (MDT)(red)	Widespread severe storms likely. Long-lived, widespread and intense.	Strong tornadoes. Widespread wind damage. Destructive hail, 2" +.
5 - HIGH (HIGH)(magenta)	Widespread severe storms expected. Long-lived, very widespread and particularly intense.	Tornado outbreak. Derecho.
* NWS defines a severe thunderstorm as measured wind gusts to at least 58 mph, and/or hail to at least one inch in diameter, and/or a tornado. All thunderstorm categories imply lightning and the potential for flooding. Categories are also tied to the probability of a severe weather event within 25 miles of your location. This table is adapted from information available on National Weather Service (NWS) Storm Prediction Center's (SPC) website.