Chicago finds itself positioned between two huge competing air masses – a center of deepening low pressure over eastern Canada and a building ridge of high pressure that covers eastern Canada and western and southern United States. Caught up in the resulting west to northwesterly flow, troughs of low pressure rotate across the Great Lakes and Chicago, keeping an expansive area of lower stratocumulus clouds over the Midwest and Great Lakes. With each trough passage, a new surge of cold air reinforces the chilly air already in place here, along with bands of snow flurries/snow showers. A cloudy day Saturday will make it seven consecutive cloudy days – tying the record for consecutive sunless days in January.
Monday a “clipper” low pressure system is forecast to swing through from the northwest, temporarily placing Chicago in the “warmer” section of the system, allowing afternoon readings Monday into Tuesday to “warm” into the middle and even upper 30s. The latter part of next week should finally see considerable sunshine here.