July 07--Monday afternoon and evening thunderstorm downpours hit portions of the Chicago area as a cold front approached from the west. Cool Canadian-source high pressure followed Tuesday with some locations experiencing a temperature drop of nearly 30 degrees from Monday's highs.
Close to the lakefront, readings topped out around 90 Monday afternoon. On Tuesday, with a strong northeast wind off the cool waters of Lake Michigan enhancing the already chilly air, afternoon readings at the same locations will struggle to reach the 60-degree mark.
Chicago will rest along the southern edge of this Canadian high pressure much of the workweek.
Periodically, low pressure will ripple along a nearly stationary, west-east frontal boundary through central Illinois producing cloudiness and occasional showers or thunderstorms. The best chance of rain here looks to be Wednesday night and again Friday.
Temperatures will moderate considerably by next weekend as southerly winds return on the back side of the departing high pressure. Warm, humid air will spread into our area with temperatures reaching into the 90s.
