Official 1981-2010 Climate Normals City: DE KALB State: IL ID: 112223 Latitude: 41.9342 Longitude: -88.7756 Elevation: 872.8 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 27.9 32.8 44.9 59.0 70.3 80.0 83.3 81.3 74.5 61.9 46.4 31.9 Mean: 20.3 24.8 35.9 48.4 59.4 69.5 73.1 71.2 63.4 51.1 38.1 24.5 Low: 12.8 16.8 27.0 37.7 48.5 58.9 62.9 61.0 52.3 40.2 29.7 17.2 CDD: 0 0 0 6 42 172 256 206 79 8 0 0 HDD: 1384 1125 901 506 216 38 5 15 127 440 809 1254 Number of Days T090: 0.0 0.0 0.0 0.0 0.5 2.9 4.1 2.9 0.6 0.0 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 T000: 5.6 3.4 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.4 T032: 29.6 25.7 22.4 7.5 0.7 0.0 0.0 0.0 0.3 6.6 17.4 28.4 ------------------------------------------------------------------------------------------ Annual Values High Temp: 58.0 F Mean Temp: 48.4 F Low Temp: 38.9 F Cooling DD: 769 Heating DD: 6820 Days above 90 (T090): 11.0 Days above 100 (T100): 0.1 Days below 0 (T000): 12.6 Days below 32 (T032): 138.5 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.48 1.54 2.27 3.27 4.57 4.14 4.37 4.36 3.25 2.88 2.70 2.15 Snow: 10.1 7.3 4.3 0.9 0.0 0.0 0.0 0.0 0.0 0.1 1.1 8.1 Number of Days P001: 10.0 7.9 10.5 11.4 11.8 10.5 9.8 9.4 8.9 9.9 9.6 10.7 P010: 4.4 3.6 5.4 7.2 8.0 7.2 6.1 6.0 5.5 5.8 5.4 5.2 P100: 0.1 0.1 0.3 0.6 1.2 1.0 1.1 1.2 0.8 0.6 0.6 0.3 S001: 7.4 4.7 3.1 0.6 0.0 0.0 0.0 0.0 0.0 0.1 1.5 6.5 S010: 3.5 2.5 1.2 0.4 0.0 0.0 0.0 0.0 0.0 0.1 0.4 2.9 S100: 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 36.98 inches Snowfall: 31.9 inches Days precipitation at or above 0 inches (P000): 120.4 Days precipitation at or above 0.10 inches (P010): 69.8 Days Precipitation at or above 1.00 inches (P100): 7.9 Days Snowfall at or above 0.1 inches (S001): 23.9 Days Snowfall at or above 1.0 inches (S010): 11.0 Days Snowfall at or above 10.0 inches (S100): 0.0 ------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------ 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