Jim Ramsey's Saturday night full and 7 day forecast.

After a brief interruption, Chicago's weather will return to normal this afternoon: Cold and freezing rain are on the way.

Since the day after Christmas, temperatures here have been primarily above freezing. And, according to National Weather Service readings at O'Hare International Airport, since a 27-degree reading about 9 a.m. Friday at O'Hare, it's always been above freezing, with a peak of 50 degrees about 3 p.m. Saturday.

That's starting to change. The 39-degree reading at O'Hare about 3 a.m. today is likely to be the high of the day; as of about 1 p.m., it was about 27 degrees there. According to ChicagoWeatherCenter.com, the temperatures should get into the low 20s by 6 p.m., and should be in the teens by 10 p.m.

Temperatures will be below zero quickly with wind chills. If you're headed to the Chicago Bears-Green Bay Packers NFL game at Soldier Field, dress extra warmly. It will be really cold.

With some precipitation in the forecast as well, the weather service has instituted a freezing rain advisory until 4 p.m. this afternoon for all of northeast Illinois and parts of northwest Indiana and southwest Michigan. Freezing drizzle will begin late this morning and extend into the afternoon, the agency said; roads will be slippery and travel could be hazardous.

The weather service has also instituted a wind chill advisory from 9 p.m. tonight until noon Monday, with winds out of the northwest at 10-15 m.p.h. resulting in temperatures that could reach 15 to 30 degrees below zero.

The cold temperatures are expected to stick around until at least Friday, with wind chill readings below zero most nights.

It won't just be cold either – the agency predicts snow Monday, Tuesday and Wednesday nights, though how much is uncertain.

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