National Weather Service United States Department of Commerce

Severe Thunderstorms and Heavy Rain in the Southern U.S.; Snow in the Northern Rockies and Northern Plains

A storm system will shift from eastern Texas into the lower Mississippi Valley today with additional threats of severe thunderstorms and heavy to excessive rainfall which may bring flooding. In the northern U.S., a storm will bring heavy snow and gusty winds over parts of the northern Rockies, northern Plains, and Upper Midwest today into Wednesday. Read More >

Automatically generated image showing areas of convective available potential energy.

 

Thumbnail of an automatically generated image showing areas of convective available potential energy. Thumbnail of an automatically generated image showing areas of convective available potential energy. Thumbnail of an automatically generated image showing areas of convective available potential energy.
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4 Panel Display | Animated Loop

CAPE 

This is a surface based Convective Available Potential Energy (CAPE) measurement only.  In the cool season, elevated instability may be much higher than surface based cape.

On average, CAPE of 1000 J/Kg is usually sufficient for strong to severe storms. CAPE of 3,000 to 4,000 J/Kg or higher is usually a signal of a very volatile atmosphere that could produce severe storms if other environmental parameters are in place.

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