Official 1981-2010 Climate Normals City: ALTON MELVIN PRICE State: IL ID: 110137 Latitude: 38.8661 Longitude: -90.1461 Elevation: 434.9 ft Temperature-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec High: 39.7 44.3 54.6 66.7 75.9 84.8 88.9 87.7 80.7 68.8 56.1 42.9 Mean: 31.4 35.3 45.2 56.6 66.3 75.6 79.7 78.2 70.6 58.8 47.3 34.9 Low: 23.0 26.4 35.8 46.5 56.8 66.4 70.4 68.6 60.5 48.7 38.5 26.9 CDD: 0 0 5 29 116 324 454 408 203 33 3 0 HDD: 1043 830 619 281 75 6 0 1 35 227 534 933 Number of Days T090: 0.0 0.0 0.0 0.1 0.8 6.8 13.9 11.0 3.9 0.1 0.0 0.0 T100: 0.0 0.0 0.0 0.0 0.0 0.0 0.5 1.0 0.0 0.0 0.0 0.0 T000: 0.8 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.7 T032: 24.0 19.3 10.5 1.3 0.0 0.0 0.0 0.0 0.0 0.2 7.2 20.5 ------------------------------------------------------------------------------------------ Annual Values High Temp: 66.0 F Mean Temp: 56.7 F Low Temp: 47.5 F Cooling DD: 1576 Heating DD: 4583 Days above 90 (T090): 36.5 Days above 100 (T100): 1.6 Days below 0 (T000): 1.9 Days below 32 (T032): 83.0 ------------------------------------------------------------------------------------------ Precipitation-Related Normals Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Prcp: 2.42 2.58 3.18 4.25 5.12 3.48 3.64 3.15 3.30 3.29 3.91 2.98 Number of Days P001: 6.8 7.4 9.7 9.9 10.6 8.2 7.5 6.9 6.6 8.3 8.9 8.1 P010: 4.8 4.7 6.8 7.3 7.6 6.0 5.6 5.4 4.8 6.1 6.6 5.7 P100: 0.8 0.6 0.5 1.0 1.5 1.0 1.1 0.9 0.9 0.8 0.9 1.0 ------------------------------------------------------------------------------------------ Annual Values Precipitation: 41.30 inches Days precipitation at or above 0 inches (P000): 98.9 Days precipitation at or above 0.10 inches (P010): 71.4 Days Precipitation at or above 1.00 inches (P100): 11.0 ------------------------------------------------------------------------------------------ ------------------------------------------------------------------------------------------ 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