Official 1981-2010 Climate Normals City: MASON CITY 2N State: IL ID: 115413 Latitude: 40.2272 Longitude: -89.6947 Elevation: 599.9 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 33.6 38.0 50.9 64.2 73.9 82.9 85.7 84.4 78.5 66.4 51.3 36.9 Mean: 24.8 28.7 40.2 52.8 62.9 72.3 75.2 73.5 66.1 54.5 41.3 28.5 Low: 16.0 19.4 29.5 41.4 51.9 61.8 64.7 62.6 53.6 42.7 31.2 20.1 CDD: 0 0 1 12 73 236 317 269 114 18 0 0 HDD: 1246 1016 770 378 138 15 1 6 82 342 713 1131 Number of Days T090: 0.0 0.0 0.0 0.0 0.6 4.1 7.1 5.6 2.3 0.1 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.1 0.2 0.1 0.0 0.0 0.0 0.0 T000: 4.0 2.2 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.4 T032: 28.5 25.2 19.1 4.9 0.1 0.0 0.0 0.0 0.2 4.6 16.6 26.0 ------------------------------------------------------------------------------------------ Annual Values High Temp: 62.3 F Mean Temp: 51.8 F Low Temp: 41.3 F Cooling DD: 1041 Heating DD: 5839 Days above 90 (T090): 19.9 Days above 100 (T100): 0.4 Days below 0 (T000): 8.6 Days below 32 (T032): 125.2 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 1.92 1.61 2.49 3.61 4.07 4.04 4.60 3.29 3.04 2.87 3.11 2.33 Snow: 5.3 4.3 1.4 0.3 0.0 0.0 0.0 0.0 0.0 0.0 0.2 3.2 Number of Days P001: 7.3 7.0 8.2 10.7 11.1 9.8 8.8 7.8 7.0 8.8 8.3 7.3 P010: 3.8 3.8 5.5 6.8 7.8 6.7 6.4 5.5 5.2 5.5 5.9 4.9 P100: 0.3 0.2 0.3 0.4 1.1 1.4 1.2 0.9 0.8 0.4 0.7 0.5 S001: 3.9 2.7 1.2 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.2 3.0 S010: 1.8 1.4 0.7 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.1 1.7 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: 36.98 inches Snowfall: 14.7 inches Days precipitation at or above 0 inches (P000): 102.1 Days precipitation at or above 0.10 inches (P010): 67.8 Days Precipitation at or above 1.00 inches (P100): 8.2 Days Snowfall at or above 0.1 inches (S001): 11.2 Days Snowfall at or above 1.0 inches (S010): 5.8 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