Official 1981-2010 Climate Normals City: WEST CHICAGO DUPAGE State: IL ID: 094892 Latitude: 41.9144 Longitude: -88.2464 Elevation: 753.7 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 31.4 36.3 48.0 60.9 71.2 81.0 85.1 82.5 75.6 63.2 49.1 35.2 Mean: 23.5 27.9 38.1 49.3 59.5 69.8 73.9 72.0 64.2 52.5 40.2 27.2 Low: 15.5 19.4 28.1 37.7 47.8 58.5 62.7 61.4 52.9 41.7 31.4 19.1 CDD: 0 0 0 4 42 178 278 222 79 11 0 0 HDD: 1288 1040 836 475 213 36 2 7 102 400 743 1173 Number of Days T090: 0.0 0.0 0.0 0.0 0.6 3.5 5.9 3.0 0.9 0.0 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 T000: 2.9 1.5 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.9 T032: 28.9 24.8 20.8 7.5 1.1 0.0 0.0 0.0 0.0 4.2 15.2 27.0 ------------------------------------------------------------------------------------------ Annual Values High Temp: 60.1 F Mean Temp: 49.9 F Low Temp: 39.8 F Cooling DD: 815 Heating DD: 6314 Days above 90 (T090): 13.9 Days above 100 (T100): 0.1 Days below 0 (T000): 6.3 Days below 32 (T032): 129.5 ------------------------------------------------------------------------------------------ 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: 1.31 1.42 2.36 3.35 4.58 3.89 4.12 4.60 3.29 3.19 3.08 1.72 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 36.91 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