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Powerful Storm to Impact Eastern Third of U.S. this weekend.

A developing storm system will bring a myriad of significant impacts this weekend. Heavy snow up to 18 inches from the Ohio Valley to the Northeast, and ice up to a quarter of an inch is forecast in places. Heavy rain may cause flash flooding from the Mid-South to the Mid-Atlantic. Severe thunderstorms with damaging winds and isolated tornadoes will be possible in the Deep South. Read More >


Storm approaching Tripp County image by Laura Welker


During the afternoon and evening of July 18, 2018, scattered strong to severe thunderstorms developed across western South Dakota. The most intense storm produced a brief tornado and significant straight-line wind damage over northeastern Tripp County, north of Hamill. Based on a storm damage survey, the highest winds of the tornado were estimated to be 90 to 100 mph, which gives it a rating of EF-1. In addition, straight-line winds snapped trees and power poles, with estimated wind speeds up to 115 mph. This storm is pictured to the left. Photo courtesy of Laura Welker from Hamill.

Farther west, a severe thunderstorm produced hail up to two inches in diameter and wind gusts to 70 mph across portions of Pennington, Custer, and Oglala Lakota Counties. The storm also produced locally heavy rainfall, which led to water over roadways across portions of Pennington County.


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