Official 1981-2010 Climate Normals City: OTTAWA 5SW State: IL ID: 116526 Latitude: 41.3283 Longitude: -88.9106 Elevation: 524.8 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 31.5 36.4 48.8 62.4 72.4 81.0 84.1 82.6 76.7 64.8 50.0 35.6 Mean: 23.3 27.7 39.0 51.2 61.5 70.7 74.2 72.5 65.3 53.5 41.0 27.6 Low: 15.1 19.0 29.3 40.0 50.5 60.4 64.4 62.4 53.9 42.1 32.0 19.6 CDD: 0 0 1 11 59 197 290 241 104 13 0 0 HDD: 1292 1044 805 425 169 26 3 9 95 371 720 1159 Number of Days T090: 0.0 0.0 0.0 0.0 0.5 2.6 4.8 3.9 1.4 0.0 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.1 0.0 0.0 0.0 0.0 T000: 4.4 2.4 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.4 T032: 28.8 25.0 19.7 5.5 0.4 0.0 0.0 0.0 0.1 3.5 14.8 26.9 ------------------------------------------------------------------------------------------ Annual Values High Temp: 60.6 F Mean Temp: 50.7 F Low Temp: 40.8 F Cooling DD: 916 Heating DD: 6120 Days above 90 (T090): 13.2 Days above 100 (T100): 0.2 Days below 0 (T000): 9.2 Days below 32 (T032): 124.7 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.48 1.43 2.46 3.22 4.11 3.98 3.85 3.89 3.26 2.80 3.11 2.13 Snow: 7.6 4.6 2.7 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.2 4.5 Number of Days P001: 8.4 6.8 9.4 11.0 11.3 9.8 8.8 9.0 7.7 8.9 9.4 9.2 P010: 4.1 3.3 5.5 6.9 7.4 6.4 6.2 6.1 5.6 5.2 5.9 5.0 P100: 0.2 0.1 0.4 0.6 1.3 1.1 1.0 1.3 0.8 0.4 0.8 0.4 S001: 4.5 3.1 1.3 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.3 3.4 S010: 3.0 2.4 0.9 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.1 2.2 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: 35.72 inches Snowfall: 20.1 inches Days precipitation at or above 0 inches (P000): 109.7 Days precipitation at or above 0.10 inches (P010): 67.6 Days Precipitation at or above 1.00 inches (P100): 8.4 Days Snowfall at or above 0.1 inches (S001): 12.8 Days Snowfall at or above 1.0 inches (S010): 8.8 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