Remnant clouds from early morning storms to our north delayed heating for a time Friday morning, but afternoon temps still reached 95 degrees at Midway airport, and at Valparaiso. Humidity levels have been stifling. Dew points as high as 81 degrees were observed at Lansing and Joliet. Heat indices peaked at 117 at Burr ridge. Officially, O’Hare airport registered a low temp of 81, setting a new record for the highest minimum temp for the date. This was also Chicago’s first 80-degree low since July 23, 2012. Similar conditions are expected on Saturday as heat indices again reach 110-115. Cooler, less humid air is due to arrive Sunday and Monday in the wake of a cold front. Thunderstorms are likely as the front passes Saturday night into Sunday. Ninety degree heat is to retreat through the middle of next week as a dome of hot air shifts west.