Official 1981-2010 Climate Normals City: GRAFTON State: IL ID: 113572 Latitude: 38.9681 Longitude: -90.4289 Elevation: 442.8 ft Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 2.44 2.29 3.07 4.07 4.52 3.81 3.82 3.27 3.38 2.97 3.68 2.87 Number of Days P001: 5.5 5.9 7.4 9.0 8.8 7.5 7.5 6.0 6.3 7.2 8.7 6.3 P010: 4.3 4.1 5.7 6.8 6.8 5.8 6.1 4.8 4.5 5.1 7.0 4.5 P100: 0.9 0.4 0.8 1.0 1.4 1.2 1.1 1.1 1.1 0.7 1.1 1.0 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 40.19 inches Days precipitation at or above 0 inches (P000): 86.1 Days precipitation at or above 0.10 inches (P010): 65.5 Days Precipitation at or above 1.00 inches (P100): 11.8 ------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------ 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