The weather observed at CHICAGO O'HARE, IL (KORD) at 07:51 PM CDT was: The skies were clear. Temperature: 90F ( 32C) Dewpoint: 64F ( 18C) Relative Humidity: 43% Winds from the SW (210 degs) at 14 mph. Pressure: 1011.6 millibars. Altimeter:29.89 inches of mercury. The prevailing visibility was 10 miles.