As snow continues to fall throughout the area, numerous flights are being delayed or canceled at the city's airports Sunday.

According to the Chicago Department of Aviation, over 500 flights have been canceled in all. Nearly all of those flights have been canceled at O'Hare, as 458 flights have been grounded there. Midway has canceled 51 flights thus far.

Flights at O'Hare that are taking off are going through significant delays, averaging nearly an hour and a half, according to the department. Over an inch of snow has already fallen at the airport, according to a report from the National Weather Service.

Anywhere from one to three inches of snow is expected to fall in the area, and snow is expected to continue throughout the day.

Meanwhile, a Winter Weather Advisory is in effect for four different counties, including McHenry, Lake, DeKalb, and LaSalle counties. Those areas could see even more snow, with up to five inches possible in some places before the system finally moves out during the overnight hours.

Snow could be more intense near the lake, according to the NBC 5 Storm Team.