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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

Sunday, January 7 saw persistent light freezing rain and drizzle over the area over a span of six to nine hours. At brief times this was mixed with sleet and snow, but was mainly an icing event during the afternoon. After dark, the precipitation gradually transitioned to snow by mid-evening.

This event came on the heels of a significant cold weather period from Dec 26-Jan 6, which meant ground and pavement temperatures were below freezing.  This furthered the icing on roads and created very hazardous travel conditions. 

A Winter Weather Advisory was issued for generally south of Interstate 80 in the early morning of January 7, and this was expanded northward early in the afternoon.

 

Radar Loop
January 7 13-hour radar loop from 10:30 a.m.-11:30 p.m.  Overlaid in yellow are mPing observations.  Symbols are drops (rain), drops with a horizontal "S" (freezing rain), S with a circle (sleet), and asterisk shape (snow).

Meteorology

Precip Types Sounding
An explanation of different precipitation types. A look at the observed atmosphere over central Illinois on January 7 that was  representative of much of the local area.

 

 

 


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