Joliet Climate Normals

Official 1981-2010 Climate Normals

City: JOLIET BRANDON RD
State: IL
ID: 114530
Latitude: 41.5033
Longitude: -88.1028
Elevation: 542.8 ft

Temperature-Related Normals

Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
High: 31.4 36.0 47.4 60.6 71.4 80.9 84.2 82.4 76.3 63.8 49.4 35.2
Mean: 24.0 28.2 38.4 49.9 60.1 70.3 74.1 72.5 65.4 53.2 41.3 28.1
Low: 16.6 20.4 29.3 39.2 48.7 59.7 63.9 62.7 54.5 42.7 33.2 20.9
CDD: 0 0 0 8 45 190 283 240 103 12 0 0
HDD: 1271 1030 827 461 199 31 3 6 91 376 711 1145

Number of Days
T090: 0.0 0.0 0.0 0.0 0.8 3.2 5.5 3.1 1.2 0.0 0.0 0.0
T100: 0.0 0.0 0.0 0.0 0.0 0.1 0.2 0.0 0.0 0.0 0.0 0.0
T000: 4.0 1.8 0.1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 1.7
T032: 27.4 23.6 19.9 5.6 0.3 0.0 0.0 0.0 0.0 2.8 13.4 25.5
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Annual Values

High Temp: 60.0 F
Mean Temp: 50.6 F
Low Temp: 41.1 F
Cooling DD: 882
Heating DD: 6151

Days above 90 (T090): 13.8
Days above 100 (T100): 0.3
Days below 0 (T000): 7.6
Days below 32 (T032): 118.4
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Precipitation-Related Normals

Normal Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Prcp: 1.80 1.71 2.25 3.49 4.08 3.88 4.33 4.16 3.01 2.84 3.06 2.20

Number of Days
P001: 10.7 8.9 10.6 11.4 11.4 10.1 9.4 9.0 8.2 9.5 10.8 11.3
P010: 4.4 4.5 5.3 6.7 7.7 6.5 6.2 5.7 5.0 5.4 5.8 5.2
P100: 0.3 0.3 0.4 0.7 0.8 0.8 1.1 1.1 0.9 0.5 0.7 0.3
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Annual Values

Precipitation: 36.81 inches

Days precipitation at or above 0 inches (P000): 121.3
Days precipitation at or above 0.10 inches (P010): 68.4
Days Precipitation at or above 1.00 inches (P100): 7.9

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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