STATION:  CONCORD BUCHANAN FIELD AIRPORT (KCCR), CA

CLIMATOLOGICAL SUMMARY.  Period of Record: Jun 1999 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        |  56.3  60.8  67.1  69.4  78.3  84.3  87.5  86.9  84.0  76.4  64.9  57.1 |   72.8
Avg Min Temp        |  39.8  42.6  45.5  47.4  52.7  56.0  58.0  58.0  55.6  50.9  44.6  40.2 |   49.3
Avg Temperature     |  48.0  51.7  56.3  58.4  65.5  70.2  72.7  72.5  69.8  63.6  54.8  48.6 |   61.0
                    |                                                                         |
Extremes:           |                                                                         |
    Extreme Max Temp|    72    76    85    94   105   109   109   105   103    99    80    74 |    109
                    |                                                                         |
    Date of Ext-Day |    13    16    15    26    31    14    24    28    18    01    04    19 |
               -Year|  2007  2007  2004  2004  2001  2000  2006  2008  2000  2001  2001  1999 |
                    |                                                                         |
    Extreme Min Temp|    24    32    33    36    43    48    49    51    45    41    29    27 |     24
                    |                                                                         |
    Date of Ext-Day |    13    13    08    24    11    07    18    20    29    31    30    19 |
               -Year|  2007  2001  2002  2008  2000  1999  1999  2002  2007  2002  2004  2006 |
                    |                                                                         |
Heating Degree Days |   525   377   275   211    63     9     2     2    12    85   307   507 |   2375
Cooling Degree Days |     0     0     4    13    78   163   242   234   157    42     0     0 |    933
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Max Temp >= 90  |   0.0   0.0   0.0   0.3   3.7   8.6  13.6  11.5   8.7   1.6   0.0   0.0 |   48.0
    Max Temp >= 75  |   0.0   0.1   5.6   7.3  19.3  26.1  28.5  28.9  25.4  17.6   2.5   0.0 |  161.3
    Max Temp <= 32  |   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0 |    0.0
                    |                                                                         |
    Min Temp <= 32  |   4.0   0.4   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.5   2.9 |    7.9
    Min Temp <= 20  |   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0 |    0.0
    Min Temp  <= 0  |   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0 |    0.0
                    |                                                                         |
Avg Dew Point Temp  |  41.1  42.4  43.7  44.1  47.5  49.5  52.4  53.0  50.4  45.4  44.7  41.3 |   46.3
Avg Wet Bulb Temp   |  44.7  46.7  49.6  50.7  55.1  57.9  59.7  60.2  58.2  52.8  49.4  45.0 |   52.5
                    |                                                                         |
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                    |                                                                         |
Avg Sea Level Pres  | 30.13 30.04 30.03 29.99 29.92 29.88 29.88 29.87 29.86 29.96 30.07 30.11 |  29.98
(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   |   0.2   0.1   0.3   0.2   0.6   0.2   0.2   0.3   0.2   0.3   0.2   0.9 |    3.8
    Heavy Fog       |   5.5   1.0   0.2   0.1   0.1   0.0   0.0   0.0   0.0   0.1   2.3   3.7 |   13.0
    Fog             |  23.9  16.7  10.1   5.7   3.5   1.0   0.6   1.8   3.6   6.0  15.9  21.6 |  110.4
    Hail            |   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.1 |    0.1
                    |                                                                         |
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                    |                                                                         |
PRECIPITATION (In)  |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Average Monthly     |  2.61  3.06  1.46  1.13  0.48  0.04  0.00  0.02  0.05  0.66  1.49  3.82 |  14.82
                    |                                                                         |
Maximum Daily       |  2.88  1.61  0.60  0.94  0.56  0.14  0.01  0.19  0.15  1.09  1.32  2.24 |   2.88
                    |                                                                         |
    Date of Ext-Day |    04    25    06    12    19    25    18    21    24    26    01    31 |
               -Year|  2008  2004  2002  2003  2002  2001  2007  2003  2001  2004  2008  2005 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    >= 0.01         |  11.7  11.2   8.4   5.6   2.6   0.7   0.1   0.1   0.8   4.1   9.9  12.5 |   67.6
    >= 0.10         |   4.8   6.6   4.3   2.9   1.4   0.1   0.0   0.1   0.2   1.3   3.0   7.5 |   32.3
    >= 0.25         |   2.8   4.3   2.5   1.9   0.8   0.0   0.0   0.0   0.0   0.7   2.1   4.6 |   19.6
    >= 0.50         |   1.0   1.8   0.6   0.7   0.3   0.0   0.0   0.0   0.0   0.4   0.8   2.1 |    7.6
    >= 1.00         |   0.4   0.4   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.2   0.3   0.9 |    2.3
                    |                                                                         |
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                    |                                                                         |
WIND (MPH)          |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Daily Avg Wind Speed|   5.0   5.7   6.9   8.3   9.3  10.6  10.6   9.6   7.3   5.8   4.7   5.1 |    7.4
Daily Avg Max 2-Min |  14.1  15.5  16.9  18.2  18.5  19.6  19.2  18.4  16.5  15.2  13.6  14.8 |   16.7
Daily Avg Peak Gust |  17.4  19.1  20.7  22.2  22.7  23.7  23.2  22.2  20.2  18.9  17.0  18.4 |   20.5
                    |                                                                         |
Maximum Daily Avg   |  17.1  16.9  16.4  16.6  18.0  20.0  20.4  19.7  17.4  18.1  17.9  19.5 |   20.4
                    |                                                                         |
Maximum 2-Minute Avg|    37    36    31    31    31    30    29    32    29    69    40    40 |     69
                    |                                                                         |
Date of Max 2min-Day|    04    17    25    17    02    01    15    20    08    30    07    14 |
               -Year|  2008  2004  2006  2007  2001  2002  2001  2001  1999  2008  2002  2003 |
                    |                                                                         |
Maximum Peak Gust   |    47    41    40    37    38    36    35    37    34    82    52    49 |     82
                    |                                                                         |
Date of Max Gust-Day|    04    17    04    15    02    20    15    20    08    30    07    14 |
               -Year|  2008  2004  2001  2002  2001  2002  2001  2001  1999  2008  2002  2002 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
   Peak Gust >=30   |   2.1   3.0   2.9   2.6   2.8   2.2   2.6   1.2   0.5   1.2   1.1   3.3 |   25.5
   Peak Gust >=40   |   0.3   0.3   0.1   0.0   0.0   0.0   0.0   0.0   0.0   0.2   0.2   0.7 |    1.9
   Peak Gust >=50   |   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.1   0.1   0.0 |    0.2
                    |                                                                         |
   Max 2-Minute >=30|   0.4   0.4   0.3   0.2   0.1   0.2   0.0   0.1   0.0   0.3   0.2   0.0 |    2.4
   Max 2-Minute >=40|   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.1   0.1   0.0 |    0.2
                    |                                                                         |
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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.