Rockford Climate Normals

Official 1981-2010 Climate Normals

City: ROCKFORD AP
State: IL
ID: 094822
Latitude: 42.1928
Longitude: -89.0931
Elevation: 729.8 ft

Temperature-Related Normals

Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
High: 29.5 34.2 46.9 60.7 71.8 81.1 84.5 82.4 75.4 62.7 47.6 33.2
Mean: 21.5 25.9 37.2 49.4 60.1 69.8 73.8 71.9 63.9 51.7 38.9 25.4
Low: 13.5 17.7 27.5 38.1 48.4 58.5 63.0 61.3 52.4 40.7 30.3 17.7
CDD: 0 0 0 8 47 175 274 223 84 9 0 0
HDD: 1348 1093 862 476 198 31 3 11 117 422 782 1226

Number of Days
T090: 0.0 0.0 0.0 0.0 0.6 3.4 5.7 4.0 1.1 0.1 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: 5.5 2.9 0.2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.9
T032: 29.0 25.0 21.8 7.5 0.5 0.0 0.0 0.0 0.3 5.1 16.8 27.4
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Annual Values

High Temp: 59.3 F
Mean Temp: 49.2 F
Low Temp: 39.2 F
Cooling DD: 820
Heating DD: 6569

Days above 90 (T090): 14.9
Days above 100 (T100): 0.2
Days below 0 (T000): 11.6
Days below 32 (T032): 133.5
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Precipitation-Related Normals

Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Prcp: 1.37 1.41 2.32 3.35 4.02 4.65 3.95 4.59 3.35 2.67 2.58 1.98
Snow: 10.2 7.7 4.8 0.9 0.0 0.0 0.0 0.0 0.0 0.1 1.7 11.3

Number of Days
P001: 9.4 8.2 10.5 11.3 12.2 10.4 9.4 9.7 8.3 9.4 10.2 10.2
P010: 4.0 3.6 5.1 6.4 7.2 7.2 6.4 6.5 5.3 5.3 5.3 5.0
P100: 0.1 0.2 0.5 0.8 1.2 1.3 0.9 1.2 0.8 0.5 0.5 0.2
S001: 8.2 5.8 4.1 1.0 0.0 0.0 0.0 0.0 0.0 0.1 1.9 7.7
S010: 3.3 2.3 1.5 0.4 0.0 0.0 0.0 0.0 0.0 0.0 0.5 3.1
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
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Annual Values

Precipitation: 36.24 inches
Snowfall: 36.7 inches

Days precipitation at or above 0 inches (P000): 119.2
Days precipitation at or above 0.10 inches (P010): 67.3
Days Precipitation at or above 1.00 inches (P100): 8.2
Days Snowfall at or above 0.1 inches (S001): 28.8
Days Snowfall at or above 1.0 inches (S010): 11.1
Days Snowfall at or above 10.0 inches (S100): 0.0

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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