Official 1981-2010 Climate Normals

City: ALTONA  
State: IL
ID: 110140
Latitude: 41.1203
Longitude: -90.1644
Elevation:  734.7 ft

Temperature-Related Pseudonormals

For stations with short records, linear combinations of normals from nearby sites were used
to compute so-called pseudonormals.

Normal    Jan    Feb    Mar    Apr    May    Jun    Jul    Aug    Sep    Oct    Nov    Dec
High:    30.1   34.8   48.3   61.5   72.3   81.0   84.3   81.9   75.9   63.6   48.1   33.7
Mean:    21.7   25.7   37.6   49.8   60.7   70.1   73.3   71.0   63.5   51.6   38.4   25.7
 Low:    13.3   16.5   26.9   38.1   49.1   59.1   62.3   60.1   51.1   39.6   28.7   17.6
 CDD:       0      0      0      2     40    171    260    192     54     10      0      0
 HDD:    1342   1101    850    458    173     20      3      7    100    426    798   1219

Number of Days
T090:     0.0    0.0    0.0    0.0    0.6    1.2    5.0    1.5    0.7    0.3    0.0    0.0
T100:     0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0
T000:     4.8    2.8    0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0    0.0    2.4
T032:    29.0   26.0   22.7    7.3    0.0    0.0    0.0    0.0    0.0    5.8   18.9   26.5
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Annual Values

 High Temp:    59.7 F
 Mean Temp:    49.2 F
  Low Temp:    38.6 F
Cooling DD:     729
Heating DD:    6496

Days above  90 (T090):     9.2
Days above 100 (T100):     0.0
Days below   0 (T000):    10.0
Days below  32 (T032):   136.3
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Precipitation-Related Pseudonormals

For stations with short records, linear combinations of normals from nearby sites were used
to compute so-called pseudonormals.

Normal    Jan    Feb    Mar    Apr    May    Jun    Jul    Aug    Sep    Oct    Nov    Dec
Prcp:    1.62   1.79   2.91   3.73   4.37   4.38   4.09   3.91   3.44   2.87   2.86   2.16
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Annual Values

Precipitation:   38.13 inches

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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