Chicago’s climatology favors northeast winds during April and May. This is common since the lake temperature tends to be much lower than the adjacent land mass, especially on sunny days. Somewhat reminiscent of the pneumonia front of April 10th, readings on Monday again varied widely across the metro area. At 6 PM, temperatures ranged from 44 at Waukegan and Northerly island, to 73 degrees at Kankakee and Joliet. The water temperature was 52 degrees at the Chicago shoreline, but much of the lake’s open waters hovered in the 42-to-45 degree range. Colder, heavier air over the lake tends to push inland during the day. On Tuesday, strengthening south winds are forecast to negate any lake breeze, allowing readings across the metro area to soar well into the 70s.