Official 1981-2010 Climate Normals City: WATERLOO State: IL ID: 119002 Latitude: 38.3664 Longitude: -90.1619 Elevation: 660.9 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 39.2 44.2 55.0 66.5 75.8 84.4 87.7 87.1 79.5 68.0 55.7 42.4 Mean: 31.2 35.5 45.7 56.2 65.6 74.5 77.9 76.8 69.1 58.0 46.7 34.5 Low: 23.3 26.8 36.4 45.8 55.4 64.6 68.2 66.4 58.8 48.0 37.7 26.6 CDD: 0 0 7 30 107 294 402 366 178 33 6 0 HDD: 1046 826 605 295 88 9 1 2 53 250 555 945 Number of Days T090: 0.0 0.0 0.0 0.2 1.0 6.8 11.5 10.3 2.9 0.0 0.1 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.1 0.5 0.8 0.0 0.0 0.0 0.0 T000: 0.9 0.6 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.6 T032: 24.3 18.5 11.5 1.8 0.0 0.0 0.0 0.0 0.0 1.0 9.3 21.5 ------------------------------------------------------------------------------------------ Annual Values High Temp: 65.5 F Mean Temp: 56.1 F Low Temp: 46.6 F Cooling DD: 1422 Heating DD: 4675 Days above 90 (T090): 32.8 Days above 100 (T100): 1.4 Days below 0 (T000): 2.1 Days below 32 (T032): 87.9 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 2.45 2.53 3.30 4.09 4.93 4.22 4.22 3.11 3.69 3.57 3.75 3.32 Snow: 4.2 3.2 0.7 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.4 2.6 Number of Days P001: 6.8 6.7 9.2 10.2 10.9 9.1 7.7 6.8 6.5 8.4 8.8 8.2 P010: 4.5 4.8 6.8 7.3 7.8 6.4 5.7 5.2 4.7 5.9 6.3 6.0 P100: 0.7 0.6 0.6 1.1 1.2 1.2 1.2 0.9 1.1 0.8 1.2 1.0 S001: 2.4 1.7 0.7 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.2 1.3 S010: 1.2 1.1 0.4 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.9 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: 43.18 inches Snowfall: 11.5 inches Days precipitation at or above 0 inches (P000): 99.3 Days precipitation at or above 0.10 inches (P010): 71.4 Days Precipitation at or above 1.00 inches (P100): 11.6 Days Snowfall at or above 0.1 inches (S001): 6.4 Days Snowfall at or above 1.0 inches (S010): 3.8 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