CHICAGO - There are two days left in May which is currently running about 1 degree per day warmer than normal.
Today and tomorrow will add to the surplus with highs in the upper 80s with a few spots tagging 90.
Skies will be mostly to partly sunny today through Thursday with a small chance of afternoon "pop-up" showers. Friday through the weekend look continued quite warm with mid to upper 80s tapering to lower 80s by Sunday. There are some reliable signs that a more-pronounced cool down will take place next week.
Sunlight interacting with gunk in our stagnant lower atmosphere will create higher levels of Ozone today warranting an air pollution action day from the EPA. This is a caution to people with respiratory difficulties to limit prolonged or strenuous outdoor activity.