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Severe Thunderstorm and Tropical Storm Bertha Impacts

Numerous severe thunderstorms are expected across a broad region from the Ohio Valley to the Mid-Atlantic and Northeast States today into tonight. Swaths of damaging wind gusts are expected and some tornadoes are possible. Bertha is expected to bring tropical storm conditions to portions of the Gulf Coast from the Florida Panhandle westward to southeastern Louisiana later today and Wednesday. Read More >

Overview

Fast Facts:

A supercell thunderstorm developed over Will County, Illinois in the very early morning hours of August 17 shortly after 2 a.m. This storm would end up sustaining itself for well over an hour as it moved into northwest Indiana. The storm was substantially deep and very well organized, a combination that resulted in large hail and severe winds. While severe storms certainly can produce both, to happen concurrently in the same location is much more rare especially with hail of 1.5" and larger and winds of 70+ mph. This storm had this based on reports, degree of damage, and radar signatures. Hail and wind damage occurred from Peotone, IL in Will County to Wheatfield, IN in Jasper County.

Radar Cross Section
NWS Chicago radar (KLOT) cross section of the powerful thunderstorm.
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Additional recaps can be found on the NWS Chicago Past Events Page
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