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Heavy Rain and Thunderstorms in the Plains; Snow in the Northern Rockies; Heavy Rain in Guam

A storm system moving over the Rockies today will bring marginal risks for excessive rainfall and severe thunderstorms from parts of New Mexico into western South Dakota. Heavy snow expected from northwestern Wyoming into southern Montana. Ongoing heavy showers and thunderstorms from Invest 96W could result in localized flash flooding, particularly in central or southern Guam early this morning. Read More >

Automatically generated image showing areas of the significant tornado parameter.

 

Thumbnail of an automatically generated image showing areas of the significant tornado parameter. Thumbnail of an automatically generated image showing areas of the significant tornado parameter. Thumbnail of an automatically generated image showing areas of the significant tornado parameter.
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Significant Tornado (SigTor) 

A composite index that includes 0-6 km bulk wind shear, 0-1 km storm-relative helicity, surface based CAPE, surface parcel CIN, and surface parcel LCL height. Values greater than 1 are indicative of increased potential of significant tornadoes.

The contours are the Lifted Condensation Level or LCL.  A lower LCL typically increases tornadic risk because it is indicative of air parcel acceleration occurring closer to the surface. 

 

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