The weather observed at CHICAGO O'HARE, IL (KORD) at 09:51 AM CST was: The skies were clear. Temperature: 46F ( 8C) Dewpoint: 37F ( 3C) Relative Humidity: 71% Winds from the CLM(CLM degs) at 0 mph. Pressure: 1023.1 millibars. Altimeter:30.20 inches of mercury. The prevailing visibility was 7 miles.