Region residents will want to get their long johns ready as temperatures are expected to reach dangerous levels below zero.
A blast of arctic air moving through Chicago and Northwest Indiana is being blamed for the cold temperatures.
David Beachler, a meteorologist with the National Weather Service, said temperatures will start to dip below zero Sunday night with an expected low ranging from 3 to 8 degrees below zero and a high of 16 degrees.
Wind chills Sunday night will dip to 25 to 30 degrees below zero.
Beachler said Sunday night's temperatures will feel mild compared with Monday's temperatures.
Monday is expected to be the coldest night in the coming days with a low that could reach 15 degrees below zero and a high of 5 degrees below zero, Beachler said. Wind chills are expected to reach 35 to 40 degrees below zero.
According to the National Weather Service, the last time the Chicago area had a high temperature that was below zero degrees was Jan. 15, 2009.
Temperatures will start to increase Tuesday with a high of 1 degree below zero and a low of 7 degrees below zero, Beachler said.
The temperatures are expected to slowly increase by Wednesday with a high of 17 degrees and a low of 12 degrees. On Thursday, temperatures are expected to reach the mid-20s.
Indiana State Police recommended keeping a full tank of gas in anticipation of next week's frigid temperatures. Troopers also recommend creating a survival kit that can include blankets, extra clothes, non-perishable food, jumper cables and a flashlight.
If a motorist becomes stranded, police recommend leaving the car on and rolling down a window for fresh air. Drivers should also check for snow around exhaust pipes to prevent carbon monoxide poisoning.
Though Northwest Indiana has been slammed with snow this week, Beachler said it's hard to say if this is an indication of what the rest of winter has in store for residents.
"Thus far we have been in a cool pattern," he said. "It's possible that it could linger around longer."