Updated 12/30/13 – 1:07 p.m.

CHICAGO (CBS) — After a mild weekend, temps have plunged below freezing, and will stay there through the end of the week, with lows in the single digits most nights. On top of that, the New Year likely could start with several inches of snow.

The temperature dropped to a low of 1 degree overnight at O’Hare International Airport, with a wind chill of 12 below zero – thanks to northerly winds of 5 to 10 mph.

Temperatures and wind chills were even lower in the northern and northwestern suburbs, with temperatures of 6 below zero in McHenry, and 5 below zero in Waukegan early Monday. The wind chills there were 22 below and 16 below, respectively.

CBS 2 Meteorologist reports temperatures Monday morning were 20 to 27 degrees colder than the same time Sunday throughout the Chicago area.

That big shift in temperatures will be followed by light snow Monday evening, though there likely will be less than an inch of accumulation.

The frigid conditions won’t get much better this week, and in addition to temperatures in the single digits Monday night, the Chicago area could get up to an inch of snow, starting around the evening rush.

More snow is expected Tuesday afternoon, and again on Wednesday and Thursday. The system could bring several inches of snow by New Year’s Day before moving east.

Though the middle of the week should bring a slight improvement in temperatures – with a high of 25 on Wednesday and 22 on Thursday – most days this week will see high temperatures in the low- to mid-teens.

Thursday night, the mercury is expected to dip to zero, followed by a high of 15 on Friday, but then temperatures will rise to about 30 on Saturday, and 28 on Sunday.