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Heavy Rain and Flash Flooding Concerns in California; Heavy Snow in the Sierra

An atmospheric river will bring heavy rainfall to lower elevations of California this week, and heavy snow to the Sierra Nevada mountains. Flash flooding, some of which may be locally considerable, will be a concern on the western foothills of the Sierra Nevada mountains through Tuesday. Landslides, rockfalls and mudslides are possible in the Southern California mountains. Read More >

Overview

During the late afternoon of August 19th, a supercell developed across northeast Wyoming and tracked directly over Devils Tower, where it caused extensive damage to trees, buildings, campers, and vehicles. The National Park Service closed Devils Tower due to the severe storm damage.  The supercell then tracked eastward through the Northern Black Hills and onto the plains of western South Dakota, and continued to produce large hail, strong winds, and heavy rain, before dissipating later in the evening.

Supercell over Devils Tower
Devils Tower
Courtesy of Thomas Winesett
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