The latest attempt at a warm-up in Chicago looks like it will be short-lived. Canadian-source high pressure will hold Monday, continuing a cooling weak northeast wind off Lake Michigan. As the high moves east, winds pick up from the southeast and finally become southwest later Tuesday, allowing warm, moist air to feed into northern Illinois. The approach of a cold front from the northwest will trigger a band of showers and thunderstorms which should hit the Chicago area Tuesday night and early Wednesday. Cool dry high pressure will follow the cold front and hold sway over the Midwest and Great Lakes into next weekend. The southern third of the United States will continue to swelter--in the 90s across the Southeast and more than 100 degrees in the Southwest.
Cool temps not really that unusual here
While this summer has been cool, a closer look at Chicago's 139 years of records shows that the overall average temperatures during the first half of summer 2009 actually barely fall in the coolest third with 91 warmer and 47 cooler. In the 51 years of observations at O'Hare Airport, 2009 ranks as the 14th coolest.
Cool temps not really that unusual here
While this summer has been cool, a closer look at Chicago's 139 years of records shows that the overall average temperatures during the first half of summer 2009 actually barely fall in the coolest third with 91 warmer and 47 cooler. In the 51 years of observations at O'Hare Airport, 2009 ranks as the 14th coolest.
