Official 1981-2010 Climate Normals City: REND LAKE DAM State: IL ID: 117187 Latitude: 38.0406 Longitude: -88.9883 Elevation: 454.9 ft Temperature-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 High: 40.9 44.3 57.0 67.7 76.3 84.8 87.4 87.8 80.9 69.3 57.0 44.1 Mean: 31.7 35.0 45.7 56.7 65.8 74.4 77.4 77.1 69.2 57.6 46.8 35.3 Low: 22.5 25.6 34.3 45.6 55.3 63.9 67.4 66.3 57.5 45.9 36.5 26.4 CDD: 0 0 3 27 103 285 385 374 176 32 2 0 HDD: 1032 841 603 277 78 5 1 0 50 262 550 922 Number of Days T090: 0.0 0.0 0.0 0.0 1.1 5.6 10.1 11.1 4.3 0.1 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.8 0.0 0.0 0.0 0.0 T000: 0.6 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.6 T032: 26.8 21.4 12.2 1.6 0.0 0.0 0.0 0.0 0.0 1.9 10.6 21.0 ------------------------------------------------------------------------------------------ Annual Values High Temp: 66.6 F Mean Temp: 56.1 F Low Temp: 45.7 F Cooling DD: 1388 Heating DD: 4622 Days above 90 (T090): 32.3 Days above 100 (T100): 0.9 Days below 0 (T000): 1.4 Days below 32 (T032): 95.4 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 2.71 2.60 3.98 4.43 5.12 4.29 3.79 2.78 3.17 3.75 4.19 3.35 Snow: 0.3 0.2 0.1 0.1 0.0 0.0 0.0 0.0 0.0 0.2 0.0 1.7 Number of Days P001: 6.6 7.0 9.5 10.9 11.7 9.2 7.9 6.4 6.9 8.3 8.5 8.0 P010: 4.1 5.2 6.7 8.1 8.2 6.2 5.3 4.7 4.7 5.5 6.3 5.7 P100: 0.3 0.6 1.2 1.0 1.7 1.3 1.3 0.8 1.0 1.0 1.2 0.6 S001: 0.5 0.4 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.7 S010: 0.3 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.4 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: 44.16 inches Snowfall: 2.6 inches Days precipitation at or above 0 inches (P000): 100.9 Days precipitation at or above 0.10 inches (P010): 70.7 Days Precipitation at or above 1.00 inches (P100): 12.0 Days Snowfall at or above 0.1 inches (S001): 1.8 Days Snowfall at or above 1.0 inches (S010): 0.9 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