Official 1981-2010 Climate Normals City: ILLINOIS CITY DAM State: IL ID: 114355 Latitude: 41.4256 Longitude: -91.0094 Elevation: 549.7 ft Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.12 1.35 2.49 3.28 4.46 4.68 3.85 4.19 3.40 2.96 2.26 1.75 Snow: 8.8 7.7 2.3 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.1 5.0 Number of Days P001: 9.5 8.6 11.0 11.0 12.4 11.7 9.4 9.9 8.4 9.5 9.6 10.8 P010: 3.4 3.8 5.4 6.8 7.5 7.9 6.3 6.1 5.5 5.4 5.2 4.9 P100: 0.1 0.1 0.5 0.8 1.3 1.3 1.3 1.3 0.9 0.8 0.4 0.2 S001: 3.2 2.2 1.1 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.1 3.3 S010: 2.7 1.9 0.8 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 2.7 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: 35.79 inches Snowfall: 24.3 inches Days precipitation at or above 0 inches (P000): 121.8 Days precipitation at or above 0.10 inches (P010): 68.2 Days Precipitation at or above 1.00 inches (P100): 9.0 Days Snowfall at or above 0.1 inches (S001): 10.1 Days Snowfall at or above 1.0 inches (S010): 8.3 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