National Weather Service United States Department of Commerce

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 >

Overview

A moist and unstable airmass combined with a front bisecting through the area to produce strong to severe thunderstorms over the lower Ohio Valley during the afternoon and early evening on July 3rd. The most significant damage from the storms was around the Poseyville, IN area where a microburst occurred with winds up to 80 mph estimated. The water vapor content of the atmosphere was quite high, helping to produce very efficient rain-producing thunderstorms and flash flooding in some areas.