CHICAGO (CBS) — Bitterly cold wind chills approaching minus 20 degrees are forecast to blow into the Chicago area starting Wednesday night, just as the massive blizzard leaves town.

A wind chill watch will be in effect for all Chicago area counties in northeast Illinois and northwest Indiana, starting Wednesday evening and lasting until Thursday morning, according to the National Weather service.

The frigid winds will immediately follow the ongoing blizzard which is forecast to drop two to five more inches of snow Wednesday morning, according CBS 2 Megan Glaros.

The sub-zero wind chills will occur later Wednesday and overnight when high winds meet “bitterly cold” temperatures ranging from minus 5 in downtown Chicago to minus 20 in outlying areas, according to the NWS.

A 15 to 20 mile per hour northwest wind could bring wind chill values as low as minus 21, according to the weather service.

Winds will subside Wednesday night, but will still be strong enough to create wind chills ranging from minus 20 to minus 40 throughout the Chicago metropolitan area, the NWS said.

The Sun-Times Media Wire contributed to this report

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