To help people understand the different safety hazards, the NWS uses risk categories from marginal to high.
Here’s what the different categories mean:
- Marginal: Isolated severe thunderstorms possible; limited in duration and/or coverage and/or intensity.
- Slight: Scattered severe storms possible; short-lived and/or not widespread; isolated intense storms possible.
- Enhanced: Numerous severe storms possible; more persistent and/or widespread; a few intense.
- Moderate: Widespread severe storms likely; long-lived, widespread and intense.
- High: Widespread severe storms expected; long-lived, very widespread and particularly intense.
Regardless of the risk categories, all thunderstorms have a threat of lightning and flooding.
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