Official 1981-2010 Climate Normals City: PERRY 6 NW State: IL ID: 116738 Latitude: 39.8058 Longitude: -90.8236 Elevation: 649.8 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 36.4 41.2 52.7 64.7 74.3 83.8 87.2 86.7 79.0 67.2 53.3 39.6 Mean: 26.7 31.1 41.6 52.8 63.2 72.5 75.9 74.3 66.2 54.4 43.0 30.4 Low: 17.1 21.1 30.6 41.0 52.0 61.2 64.5 62.0 53.4 41.5 32.7 21.1 CDD: 0 0 1 16 77 240 337 293 120 17 1 0 HDD: 1186 948 725 380 134 15 1 4 84 347 661 1074 Number of Days T090: 0.0 0.0 0.0 0.1 0.8 5.9 10.6 9.2 2.8 0.2 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.3 0.4 0.0 0.0 0.0 0.0 T000: 3.1 1.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.1 T032: 28.4 24.1 17.9 5.4 0.3 0.0 0.0 0.0 0.2 5.0 14.9 26.8 ------------------------------------------------------------------------------------------ Annual Values High Temp: 63.9 F Mean Temp: 52.8 F Low Temp: 41.6 F Cooling DD: 1102 Heating DD: 5559 Days above 90 (T090): 29.5 Days above 100 (T100): 0.7 Days below 0 (T000): 5.3 Days below 32 (T032): 122.9 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.89 1.81 2.59 3.78 4.22 4.30 4.33 3.84 3.63 3.06 3.31 2.45 Snow: 7.1 5.4 2.7 0.3 0.0 0.0 0.0 0.0 0.0 0.0 1.0 5.4 Number of Days P001: 9.2 7.4 9.5 11.4 12.4 10.5 9.0 9.3 7.8 8.7 8.5 8.9 P010: 4.3 4.0 5.4 7.1 7.1 6.9 5.8 6.1 5.3 5.7 5.4 4.7 P100: 0.6 0.4 0.3 1.0 0.9 1.5 1.1 1.1 0.9 0.6 0.6 0.6 S001: 5.1 3.6 1.4 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.5 3.9 S010: 2.6 1.8 0.9 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.3 2.3 S100: 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 39.21 inches Snowfall: 21.9 inches Days precipitation at or above 0 inches (P000): 112.6 Days precipitation at or above 0.10 inches (P010): 67.8 Days Precipitation at or above 1.00 inches (P100): 9.6 Days Snowfall at or above 0.1 inches (S001): 14.8 Days Snowfall at or above 1.0 inches (S010): 8.1 Days Snowfall at or above 10.0 inches (S100): 0.1 ------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------ 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