A dense fog advisory issued for the entire Chicago area Monday will continue through the morning, the National Weather Service said, with visibility below a mile in parts to the north and west, including in Waukegan, Aurora and DeKalb.

The heavy fog led to a ground stop at Chicago’s International Midway Airport Sunday, with two dozen flights canceled.

According to the NWS, the dense fog advisory will last until 11 a.m. Monday.

“Motorists should stay alert and be prepared to encounter sudden drops in visibility,” the NWS warned, with visibility dropping to near zero at times. “Drive slowly, and keep your distance from other vehicles.”

Monday morning also started out rainy, Roman said, with a few spotty showers passing through, and a pockets of drizzle or a brief light shower possible through the morning commute.

According to Roman, Monday would remain mostly cloudy throughout the day, with some breaks for sun.

But there’s a silver lining, Roman said, as temperatures would remain mild and on the warmer side, with highs in the upper 40s to mid 50s.

Starting Tuesday however, temperatures will drop, with highs in the upper 30s to near 40.

“A lot cooler for your Tuesday,” Roman said.

Waves of chances for light snow also arrive Tuesday, Roman said, with the first chance for a light rain-snow mix arriving late Tuesday into Wednesday morning.

Thursday afternoon brings another chance for a wintry mix, Roman said, followed by more chances for flurries Friday morning.

“Now a whole lot, but definitely seeing some chances for snow,” Roman said, of how much precipitation the area could see.

Colder temperatures move in over the weekend, as Saturday, Dec. 21 marks the Winter Solstice.

“The first day of winter is Saturday, and it will definitely feel like it, with 30 degrees,” Roman said, of Saturday’s forecast.

By Christmas Day, temperatures were expected to rebound, Roman said, with a high of 41 degrees.