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Powerful Pacific System Impacting the West; First Significant Snow for Portions of the East

Power Pacific system will continue to bring significant impacts for Pacific Northwest into northern California the remainder of the week. Dangerous coastal affects, heavy rain, flooding, strong winds, and higher elevation mountain snow continues. Meanwhile, a storm across the east is set to bring the first accumulating snow to many higher elevations of the Catskills into the central Appalachians. Read More >

Overview

On the afternoon of July 17th, 2018, thunderstorms developed over the Black Hills. Some of these storms became severe, producing large hail and damaging winds. However, the main issue with these storms was a significant amount of small hail, covering the roads and making travel difficult. Snow plows were needed to clear inches of hail from the roads. Additionally, heavy rain caused flash flooding, which was exacerbated by hail-covered roads. The storms over the Black Hills eventually moved southeast onto the plains. More thunderstorms moved into northeastern Wyoming, becoming severe and producing large hail and strong winds. Heavy rain with these storms also produced flash flooding. These storms merged to form one storm system (what meteorologists call a mesoscale convective system, or MCS), and spread into South Dakota. 

 

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