Official 1981-2010 Climate Normals City: WALNUT State: IL ID: 118916 Latitude: 41.5519 Longitude: -89.5989 Elevation: 689.8 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 29.4 34.1 46.7 60.8 71.5 80.7 83.6 81.7 75.3 62.9 47.9 33.5 Mean: 20.9 25.5 37.3 49.6 60.6 70.0 73.3 71.3 63.6 51.5 38.8 25.2 Low: 12.3 16.9 27.8 38.4 49.7 59.3 63.1 60.9 51.9 40.0 29.8 16.9 CDD: 0 0 0 10 53 180 264 209 80 9 0 0 HDD: 1368 1106 861 472 190 30 5 14 123 429 785 1234 Number of Days T090: 0.0 0.0 0.0 0.1 0.6 2.6 5.4 3.2 0.9 0.0 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.2 0.2 0.0 0.0 0.0 0.0 T000: 6.1 3.6 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3.8 T032: 29.7 25.7 21.3 6.7 0.4 0.0 0.0 0.0 0.4 6.9 17.9 27.9 ------------------------------------------------------------------------------------------ Annual Values High Temp: 59.1 F Mean Temp: 49.1 F Low Temp: 39.0 F Cooling DD: 806 Heating DD: 6615 Days above 90 (T090): 12.8 Days above 100 (T100): 0.4 Days below 0 (T000): 13.6 Days below 32 (T032): 137.1 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.29 1.57 2.15 3.18 4.36 4.56 3.85 4.44 3.12 2.89 2.44 1.96 Snow: 9.9 7.7 3.3 0.6 0.0 0.0 0.0 0.0 0.0 0.1 1.4 9.2 Number of Days P001: 5.7 5.0 6.8 8.2 8.7 8.3 7.3 7.9 6.6 6.8 5.9 6.9 P010: 3.7 3.5 5.0 6.6 7.3 7.3 5.9 6.7 5.3 5.3 5.0 5.0 P100: 0.1 0.2 0.3 0.6 1.2 1.2 1.0 1.6 0.8 0.8 0.5 0.2 S001: 4.2 2.8 1.4 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.6 3.6 S010: 3.9 2.5 1.4 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.6 3.4 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: 35.81 inches Snowfall: 32.2 inches Days precipitation at or above 0 inches (P000): 84.1 Days precipitation at or above 0.10 inches (P010): 66.6 Days Precipitation at or above 1.00 inches (P100): 8.5 Days Snowfall at or above 0.1 inches (S001): 12.9 Days Snowfall at or above 1.0 inches (S010): 12.1 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