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Areas of Excessive Heat and Excessive Rainfall Today

Dangerously hot conditions are occurring today in southeast Oklahoma, the ArkLaTex, lower Mississippi Valley, and Puerto Rico. Hot temperatures surround this area throughout the southern U.S. Excessive Heat Warnings and Heat Advisories in effect. Excessive rainfall may lead to flash flooding today over parts of northern Alabama into eastern Tennessee and the Cascades. Read More >

Overview

On June 29, 2019 a surface boundary was located across south central South Dakota. Very strong instability along the boundary was realized when a thunderstorm exploded along it. The thunderstorm updraft stretched energy along the boundary into a very slow moving tornado near Allen, SD.

The tornado was visible for many miles. It was unusual because it only moved within a two mile area, but lasted about 40 minutes. Fortunately, it spun over corn fields most of the time. It damaged a house, blew over a couple of grain bins, snapped power poles, and carried grain bags. The tornado was rated EF-1 by an NWS storm survey team.

More information about the environment of the Allen tornado can be found here

Tornado near Allen, SD
Courtesy Chris O.
Tornado near Allen, SD Tornado near Allen, SD Tornado near Allen, SD
Courtesy Gail S. Courtesy Josie D. Courtesy Ang G.
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