Official 1981-2010 Climate Normals City: CHICAGO MIDWAY AP State: IL ID: 014819 Latitude: 41.7372 Longitude: -87.7775 Elevation: 619.9 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 31.5 35.8 46.8 59.2 70.2 79.9 84.2 82.1 75.3 62.8 48.6 35.3 Mean: 24.8 28.7 38.8 50.4 60.9 71.0 75.9 74.1 66.4 54.2 41.5 29.0 Low: 18.2 21.7 30.9 41.7 51.6 62.1 67.5 66.2 57.5 45.7 34.5 22.7 CDD: 0 0 1 12 61 210 338 288 119 16 0 0 HDD: 1245 1015 812 448 188 31 1 4 77 349 704 1116 Number of Days T090: 0.0 0.0 0.0 0.0 0.6 3.1 6.3 3.8 1.2 0.0 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.1 0.3 0.1 0.0 0.0 0.0 0.0 T000: 3.0 1.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.1 T032: 27.1 23.2 17.2 3.3 0.1 0.0 0.0 0.0 0.0 1.1 12.0 24.3 ------------------------------------------------------------------------------------------ Annual Values High Temp: 59.4 F Mean Temp: 51.4 F Low Temp: 43.5 F Cooling DD: 1045 Heating DD: 5989 Days above 90 (T090): 15.1 Days above 100 (T100): 0.4 Days below 0 (T000): 5.2 Days below 32 (T032): 108.3 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 2.06 1.94 2.72 3.64 4.13 4.06 4.01 3.99 3.31 3.24 3.42 2.57 Snow: 11.5 9.1 5.4 1.0 0.0 0.0 0.0 0.0 0.0 0.1 1.3 8.7 Number of Days P001: 10.7 8.8 11.2 11.1 11.4 10.3 9.9 9.0 8.2 10.2 11.2 11.1 P010: 5.0 4.5 6.1 7.1 7.6 6.5 6.5 6.3 5.3 6.1 6.2 5.3 P100: 0.2 0.2 0.3 0.9 1.0 1.3 1.0 1.3 0.7 0.8 0.8 0.5 S001: 8.1 5.5 3.8 0.7 0.0 0.0 0.0 0.0 0.0 0.1 1.8 6.7 S010: 3.7 2.8 1.5 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.5 2.6 S100: 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 39.09 inches Snowfall: 37.1 inches Days precipitation at or above 0 inches (P000): 123.1 Days precipitation at or above 0.10 inches (P010): 72.5 Days Precipitation at or above 1.00 inches (P100): 9.0 Days Snowfall at or above 0.1 inches (S001): 26.7 Days Snowfall at or above 1.0 inches (S010): 11.4 Days Snowfall at or above 10.0 inches (S100): 0.1 ------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------ KEY: High - average daily high temperature, degrees F Mean - average daily mean temperature, degrees F Low - average daily low temperature, degrees F CDD - cooling degree days, base 50F HDD - heating degree days, base 50F T090 - number of Days with Temperatures above 90 degrees F T100 - number of Days with Temperatures above 100 degrees F T000 - number of Days with Temperatures below 0 degrees F T032 - number of Days with Temperatures below 32 degrees F Prcp - precipitation, inches Snow - snowfall, inches P001 - number of Days with Precipitation of 0.01 inches or more P010 - number of Days with Precipitation of 0.10 inches or more P100 - number of Days with Precipitation of 1.00 inches or more S001 - number of Days with Snowfall of 0.1 inches or more S010 - number of Days with Snowfall of 1.0 inches or more S100 - number of Days with Snowfall of 10.0 inches or more Page Source: Dr. Jim Angel, State Climatologist Illinois State Water Survey Prairie Research Institute University of Illinois Data Source: NOAA National Climatic Data Center