The weather observed at CHICAGO O'HARE, IL (KORD) at 05:51 PM CDT was: The skies were mostly cloudy. Temperature: 81F ( 27C) Dewpoint: 54F ( 12C) Relative Humidity: 39% Winds from the S (190 degs) at 24 mph. Pressure: 1009.6 millibars. Altimeter:29.82 inches of mercury. The prevailing visibility was 10 miles.