Official 1981-2010 Climate Normals City: CHICAGO WAUKEGAN RGNL State: IL ID: 014880 Latitude: 42.4167 Longitude: -87.8667 Elevation: 726.8 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 30.5 33.5 43.9 55.3 65.9 75.7 80.3 79.0 71.4 59.9 46.7 34.4 Mean: 23.0 25.9 35.2 46.1 55.7 65.7 71.3 69.9 62.2 51.0 39.1 27.5 Low: 15.5 18.3 26.5 36.8 45.5 55.6 62.2 60.8 53.1 42.2 31.4 20.5 CDD: 0 0 0 4 21 105 205 167 55 7 0 0 HDD: 1302 1095 924 572 309 86 12 16 138 440 779 1164 Number of Days T090: 0.0 0.0 0.0 0.0 0.2 0.8 2.5 1.7 0.2 0.0 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 T000: 2.7 1.6 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.4 T032: 29.0 26.3 22.7 8.5 1.0 0.0 0.0 0.0 0.0 4.0 15.9 25.9 ------------------------------------------------------------------------------------------ Annual Values High Temp: 56.5 F Mean Temp: 47.8 F Low Temp: 39.1 F Cooling DD: 564 Heating DD: 6834 Days above 90 (T090): 5.4 Days above 100 (T100): 0.0 Days below 0 (T000): 5.8 Days below 32 (T032): 133.4 ------------------------------------------------------------------------------------------ Precipitation-Related Pseudonormals For stations with short records, linear combinations of normals from nearby sites were used to compute so-called pseudonormals. Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.39 1.66 2.32 3.48 4.01 3.88 3.88 3.83 3.46 2.92 2.76 2.00 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 35.59 inches ------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------ 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