STATION:  DENVER INTERNATIONAL AIRPORT (KDEN), CO

CLIMATOLOGICAL SUMMARY.  Period of Record: Jul 1996 to Dec 2008

Summaries based on unedited daily ASOS data.  Errors may be present.

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TEMPERATURE (F)     |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Avg Max Temp        |  44.1  45.5  54.6  61.1  71.9  82.1  90.4  86.3  77.8  65.2  52.4  43.3 |   64.6
Avg Min Temp        |  18.5  19.9  26.6  33.3  43.2  51.8  60.3  57.8  48.6  36.8  25.9  18.2 |   36.7
Avg Temperature     |  31.3  32.7  40.6  47.2  57.6  67.0  75.4  72.1  63.2  51.0  39.2  30.7 |   50.6
                    |                                                                         |
Extremes:           |                                                                         |
    Extreme Max Temp|    72    77    79    85    94   102   105   104    95    89    80    72 |    105
                    |                                                                         |
    Date of Ext-Day |    02    28    20    13    29    14    20    01    04    01    08    02 |
               -Year|  1997  2006  1997  2006  2003  2006  2005  2008  1998  2005  2006  1998 |
                    |                                                                         |
    Extreme Min Temp|   -14   -18    -4     6    21    31    44    42    25     3    -3   -19 |    -19
                    |                                                                         |
    Date of Ext-Day |    12    02    02    12    03    08    02    28    27    26    15    22 |
               -Year|  1997  2007  2002  1997  2008  2007  1997  2004  1996  1997  1997  1998 |
                    |                                                                         |
Heating Degree Days |  1043   913   756   536   254    69     3    11   127   438   775  1062 |   5988
Cooling Degree Days |     0     0     0     1    24   128   324   229    73     5     0     0 |    784
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Max Temp >= 90  |   0.0   0.0   0.0   0.0   0.6   8.8  19.1  11.2   3.0   0.0   0.0   0.0 |   42.7
    Max Temp >= 75  |   0.0   0.1   1.1   4.6  14.3  23.2  30.4  28.8  20.5   8.3   1.1   0.0 |  132.4
    Max Temp <= 32  |   5.4   4.3   1.8   0.4   0.0   0.0   0.0   0.0   0.0   0.4   2.9   6.3 |   21.5
                    |                                                                         |
    Min Temp <= 32  |  28.8  27.1  24.2  14.6   3.5   0.1   0.0   0.0   1.0   9.1  22.9  29.3 |  160.7
    Min Temp <= 20  |  17.2  13.5   6.6   1.3   0.0   0.0   0.0   0.0   0.0   0.6   7.3  17.3 |   63.8
    Min Temp  <= 0  |   1.5   1.2   0.2   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.5   2.0 |    5.4
                    |                                                                         |
Avg Dew Point Temp  |  15.0  16.2  20.8  26.6  37.1  42.8  48.2  49.1  39.8  29.3  20.3  15.2 |   30.0
Avg Wet Bulb Temp   |  25.2  26.5  32.4  38.0  47.1  53.6  59.2  58.2  50.5  40.6  31.4  25.0 |   40.6
                    |                                                                         |
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                    |                                                                         |
Avg Sea Level Pres  | 30.08 30.06 30.05 30.07 29.97 29.93 29.90 29.93 29.96 30.03 30.07 30.09 |  30.01
(Inches of Mercury) |                                                                         |
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                    |                                                                         |
WEATHER             |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
See disclaimer below|                                                                         |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Thunderstorms   |   0.0   0.1   0.5   2.3   6.3   9.8   9.6   9.9   4.6   1.2   0.2   0.1 |   44.5
    Heavy Fog       |   3.2   3.2   3.6   2.8   1.8   0.8   1.1   1.2   1.3   2.1   2.3   1.2 |   24.6
    Fog             |   9.1   9.5   9.5  11.1   8.2   5.5   4.6   5.5   5.6   6.5   7.3   6.4 |   88.6
    Hail            |   0.0   0.0   0.0   0.4   1.1   1.1   0.6   0.6   0.2   0.0   0.0   0.0 |    4.0
                    |                                                                         |
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                    |                                                                         |
PRECIPITATION (In)  |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Average Monthly     |  0.28  0.26  0.70  1.84  1.89  1.77  2.26  2.05  0.98  1.04  0.39  0.33 |  13.79
                    |                                                                         |
Maximum Daily       |  0.42  0.30  0.85  2.09  1.77  1.50  2.71  1.62  1.22  2.48  0.43  0.73 |   2.71
                    |                                                                         |
    Date of Ext-Day |    28    08    18    24    17    18    30    18    18    13    05    20 |
               -Year|  2001  2001  2003  2007  2000  2003  1997  2004  1996  2007  2000  2006 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    >= 0.01         |   4.0   5.2   6.1   9.1   8.7   7.7   7.5   9.0   6.9   5.5   4.6   4.2 |   78.5
    >= 0.10         |   0.9   0.8   2.2   4.8   4.7   4.3   3.9   4.7   3.3   2.4   1.5   0.9 |   34.4
    >= 0.25         |   0.1   0.2   1.0   1.9   2.5   2.2   2.2   2.5   1.0   1.2   0.2   0.2 |   15.2
    >= 0.50         |   0.0   0.0   0.2   0.7   1.2   1.2   1.2   1.3   0.5   0.5   0.0   0.1 |    6.8
    >= 1.00         |   0.0   0.0   0.0   0.5   0.2   0.2   0.5   0.3   0.1   0.2   0.0   0.0 |    2.1
                    |                                                                         |
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                    |                                                                         |
WIND (MPH)          |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Daily Avg Wind Speed|   9.6   9.8  10.6  11.6  10.5  10.4   9.7   9.5   9.4   9.7   9.4  10.0 |   10.0
Daily Avg Max 2-Min |  20.6  21.3  23.1  26.1  25.0  25.7  25.4  24.1  21.8  20.9  20.0  20.9 |   22.9
Daily Avg Peak Gust |  24.2  25.1  27.6  31.6  30.7  31.8  31.0  29.2  26.6  25.0  23.5  24.5 |   27.6
                    |                                                                         |
Maximum Daily Avg   |  18.8  26.0  23.4  25.3  23.0  22.6  16.9  17.0  19.6  24.7  20.9  26.1 |   26.1
                    |                                                                         |
Maximum 2-Minute Avg|    41    48    52    53    49    49    54    49    45    46    58    54 |     58
                    |                                                                         |
Date of Max 2min-Day|    15    24    27    11    20    10    28    20    16    31    01    29 |
               -Year|  1999  2007  1997  2001  2001  1999  1999  2001  2006  2001  2003  2005 |
                    |                                                                         |
Maximum Peak Gust   |    49    60    56    60    61    63    64    61    54    56    61    64 |     64
                    |                                                                         |
Date of Max Gust-Day|    13    24    27    11    22    22    28    20    16    22    14    29 |
               -Year|  2002  2007  1997  2001  2008  1999  1999  2001  2006  2007  2005  2005 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
   Peak Gust >=30   |   7.8   7.8  11.3  16.3  15.9  15.9  15.5  14.1   9.3   7.6   6.0   7.3 |  134.8
   Peak Gust >=40   |   2.1   2.0   2.8   6.7   5.1   5.2   4.8   2.8   1.7   2.2   1.5   1.7 |   38.6
   Peak Gust >=50   |   0.0   0.4   0.7   1.1   0.8   1.3   1.2   0.2   0.2   0.3   0.4   0.5 |    7.0
                    |                                                                         |
   Max 2-Minute >=30|   4.3   4.1   5.6  10.3   8.3   9.0   8.4   5.6   4.6   4.2   3.5   0.0 |   68.0
   Max 2-Minute >=40|   0.2   0.5   0.7   1.4   0.9   1.3   1.2   0.3   0.3   0.2   0.5   0.0 |    7.5
                    |                                                                         |
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Observations of WEATHER may me innacurate due to early ASOS inconsistancies.  Average days
with Thunderstorms may be low due to early mis-detection.

Heavy Fog = Visibility less than or equal to 1/4 mile.
Fog = Visibility greater than 1/4 mile or less than 7 miles.
Peak Gust = Maximum 5-second average.
Snowfall data not observed at ASOS stations.

Copyright ©2009 Western Regional Climate Center - Desert Research Institute - Reno, Nevada.