STATION:  VACAVILLE NUT TREE AIRPORT (KVCB), CA

CLIMATOLOGICAL SUMMARY.  Period of Record: Apr 1998 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        |  55.5  60.6  67.4  70.8  80.1  88.5  94.1  93.0  88.4  78.4  65.2  56.8 |   74.9
Avg Min Temp        |  38.2  40.6  43.5  45.4  51.5  57.0  59.7  58.6  56.0  49.7  43.0  38.3 |   48.5
Avg Temperature     |  46.8  50.6  55.4  58.1  65.8  72.8  76.9  75.8  72.2  64.1  54.1  47.6 |   61.7
                    |                                                                         |
Extremes:           |                                                                         |
    Extreme Max Temp|    71    77    87    95   106   110   114   108   106   104    85    76 |    114
                    |                                                                         |
    Date of Ext-Day |    05    27    16    26    31    14    23    15    02    01    14    20 |
               -Year|  2003  2002  2004  2004  2001  2000  2006  2008  1998  2001  2008  1999 |
                    |                                                                         |
    Extreme Min Temp|    20    26    29    32    38    43    49    48    42    34    28    17 |     17
                    |                                                                         |
    Date of Ext-Day |    14    08    08    09    17    08    12    23    30    31    18    23 |
               -Year|  2007  2003  2002  1999  1998  1999  2001  2002  2007  2002  2000  1998 |
                    |                                                                         |
Heating Degree Days |   564   407   302   222    73     8     0     0     7    85   328   541 |   2537
Cooling Degree Days |     0     0     5    15    97   240   370   335   224    56     1     0 |   1343
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Max Temp >= 90  |   0.0   0.0   0.0   0.7   5.7  13.6  23.2  22.7  14.3   2.8   0.0   0.0 |   82.9
    Max Temp >= 75  |   0.0   0.5   6.6  10.4  21.5  28.0  30.9  30.6  28.2  21.1   3.5   0.3 |  181.7
    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  |   6.9   2.5   0.5   0.2   0.0   0.0   0.0   0.0   0.0   0.0   1.4   6.3 |   17.8
    Min Temp <= 20  |   0.1   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.4 |    0.5
    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  |  39.3  40.9  41.8  42.6  46.7  49.2  52.5  51.4  47.0  42.4  42.7  38.6 |   44.6
Avg Wet Bulb Temp   |  43.4  46.0  48.8  50.4  55.6  59.5  62.2  61.3  58.0  52.8  48.5  43.5 |   52.5
                    |                                                                         |
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                    |                                                                         |
Avg Sea Level Pres  | 30.15 30.07 30.05 30.00 29.93 29.87 29.86 29.86 29.86 29.97 30.09 30.15 |  29.99
(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   |   0.1   0.5   0.6   0.3   0.2   0.0   0.1   0.5   0.3   0.1   0.1   0.2 |    2.9
    Heavy Fog       |   7.8   1.4   0.6   0.0   0.1   0.0   0.0   0.0   0.0   0.1   2.5   3.8 |   16.3
    Fog             |  20.7  13.9   9.1   4.7   2.8   0.6   0.1   0.3   1.1   4.0  14.5  18.6 |   90.6
    Hail            |   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
                    |                                                                         |
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                    |                                                                         |
PRECIPITATION (In)  |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Average Monthly     |  3.74  5.05  2.61  1.33  0.92  0.08  0.01  0.04  0.09  0.91  2.60  5.81 |  23.18
                    |                                                                         |
Maximum Daily       |  2.61  2.59  1.90  1.11  1.73  0.18  0.09  0.20  0.23  1.24  3.13  4.50 |   4.50
                    |                                                                         |
    Date of Ext-Day |    04    13    14    11    28    08    18    21    19    19    07    13 |
               -Year|  2008  2000  2003  2006  1998  2005  2007  2003  2004  2004  2002  2002 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    >= 0.01         |  13.8  11.3   9.1   5.3   3.6   1.0   0.1   0.3   0.9   3.2  10.3  12.5 |   71.4
    >= 0.10         |   6.6   8.0   5.3   2.9   1.9   0.5   0.0   0.2   0.5   2.0   4.6   8.1 |   40.5
    >= 0.25         |   4.7   5.5   3.8   2.3   1.4   0.0   0.0   0.0   0.0   1.4   2.9   5.8 |   27.8
    >= 0.50         |   2.5   3.7   1.9   0.7   0.6   0.0   0.0   0.0   0.0   0.7   1.5   3.6 |   15.3
    >= 1.00         |   0.7   1.5   0.5   0.2   0.2   0.0   0.0   0.0   0.0   0.1   0.6   1.6 |    5.4
                    |                                                                         |
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                    |                                                                         |
WIND (MPH)          |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Daily Avg Wind Speed|   4.6   5.4   6.1   6.8   7.0   7.4   7.0   6.5   5.7   5.3   4.3   4.7 |    5.9
Daily Avg Max 2-Min |  13.5  15.2  16.5  17.7  17.5  17.3  15.9  15.3  15.2  14.9  13.2  14.2 |   15.5
Daily Avg Peak Gust |  17.3  19.7  21.1  22.7  22.3  22.3  20.2  19.8  19.7  19.3  17.2  18.5 |   20.0
                    |                                                                         |
Maximum Daily Avg   |  19.5  20.6  21.6  18.0  22.0  18.5  14.4  18.2  23.2  23.8  17.9  19.9 |   23.8
                    |                                                                         |
Maximum 2-Minute Avg|    35    35    39    36    36    33    28    32    41    39    33    36 |     41
                    |                                                                         |
Date of Max 2min-Day|    04    07    25    22    02    13    30    05    22    22    06    29 |
               -Year|  2008  2001  2006  1999  2001  2000  2003  2007  2006  2000  2000  2003 |
                    |                                                                         |
Maximum Peak Gust   |    48    46    47    47    51    43    33    39    52    48    46    45 |     52
                    |                                                                         |
Date of Max Gust-Day|    04    07    25    22    22    16    30    05    22    22    24    29 |
               -Year|  2008  2001  2006  1999  2008  1998  2003  2007  2006  2000  2001  2003 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
   Peak Gust >=30   |   3.1   3.9   4.6   5.3   3.3   2.0   0.6   0.9   3.1   3.5   2.7   4.0 |   37.1
   Peak Gust >=40   |   0.5   0.6   0.8   1.0   0.4   0.6   0.0   0.0   0.1   0.5   0.6   0.7 |    5.8
   Peak Gust >=50   |   0.0   0.0   0.0   0.0   0.1   0.0   0.0   0.0   0.1   0.0   0.0   0.0 |    0.2
                    |                                                                         |
   Max 2-Minute >=30|   0.9   0.9   1.0   1.2   0.6   0.6   0.0   0.1   0.4   0.7   0.8   0.0 |    7.1
   Max 2-Minute >=40|   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.1   0.0   0.0   0.0 |    0.1
                    |                                                                         |
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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.