STATION:  OAKLAND INTL AIRPORT (KOAK), CA

CLIMATOLOGICAL SUMMARY.  Period of Record: Jan 2000 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        |  56.6  59.6  63.4  64.4  68.6  71.2  71.5  72.1  73.5  69.7  63.0  57.2 |   65.9
Avg Min Temp        |  41.4  44.1  46.1  48.2  51.7  53.8  56.0  56.2  54.5  50.6  45.6  42.6 |   49.2
Avg Temperature     |  49.0  51.9  54.8  56.3  60.2  62.5  63.7  64.2  64.0  60.2  54.3  49.9 |   57.6
                    |                                                                         |
Extremes:           |                                                                         |
    Extreme Max Temp|    69    72    86    88    99   100    98    93    98    93    85    69 |    100
                    |                                                                         |
    Date of Ext-Day |    08    27    10    26    15    14    22    09    13    26    15    08 |
               -Year|  2007  2002  2004  2004  2008  2000  2006  2002  2003  2003  2008  2006 |
                    |                                                                         |
    Extreme Min Temp|    28    32    34    38    42    46    49    49    46    40    31    30 |     28
                    |                                                                         |
    Date of Ext-Day |    14    08    11    03    09    07    23    15    24    31    30    04 |
               -Year|  2007  2003  2006  2001  2003  2005  2000  2000  2005  2002  2004  2004 |
                    |                                                                         |
Heating Degree Days |   497   371   320   264   166    99    65    53    66   158   322   468 |   2847
Cooling Degree Days |     0     0     2     3    16    23    26    27    37     8     1     0 |    142
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Max Temp >= 90  |   0.0   0.0   0.0   0.0   0.6   1.1   0.7   0.7   1.6   0.3   0.0   0.0 |    4.9
    Max Temp >= 75  |   0.0   0.0   2.6   2.4   4.4   6.1   5.7   7.3  10.2   8.2   0.7   0.0 |   47.6
    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  |   1.6   0.2   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.3   0.4 |    2.6
    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  |  42.7  44.1  45.5  46.0  49.9  52.0  54.6  54.9  53.6  49.7  46.5  43.3 |   48.6
Avg Wet Bulb Temp   |  46.1  48.1  49.9  50.8  54.2  56.2  57.9  58.2  57.6  54.2  50.5  47.0 |   52.6
                    |                                                                         |
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                    |                                                                         |
Avg Sea Level Pres  | 30.16 30.09 30.09 30.06 30.00 29.96 29.96 29.95 29.94 30.01 30.12 30.14 |  30.04
(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   0.9   0.1   0.3   0.1   1.7   1.1   1.3   1.0   1.7   1.4   0.7 |   10.6
    Heavy Fog       |   1.2   0.8   0.3   0.1   0.0   0.1   0.0   0.1   0.4   1.1   1.1   1.2 |    6.6
    Fog             |  18.7  14.1  12.0   7.1   7.2   5.4   6.2   5.9   7.4   8.6  13.3  16.7 |  122.6
    Hail            |   0.1   0.3   0.2   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0 |    0.7
                    |                                                                         |
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                    |                                                                         |
PRECIPITATION (In)  |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Average Monthly     |  2.78  3.48  2.20  1.45  0.57  0.10  0.01  0.01  0.09  1.03  1.73  4.82 |  18.27
                    |                                                                         |
Maximum Daily       |  2.00  2.01  1.08  0.77  0.63  0.36  0.02  0.02  0.30  1.84  1.76  2.54 |   2.54
                    |                                                                         |
    Date of Ext-Day |    23    13    05    12    08    08    13    25    24    19    08    13 |
               -Year|  2000  2000  2006  2003  2005  2005  2000  2000  2001  2004  2002  2002 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    >= 0.01         |  12.2  12.2   9.5   7.0   3.1   1.0   0.4   0.9   2.1   6.0  10.0  12.7 |   77.1
    >= 0.10         |   6.1   7.5   5.8   4.2   1.6   0.4   0.0   0.0   0.3   2.4   3.5   7.8 |   39.6
    >= 0.25         |   3.6   4.7   3.3   2.2   1.2   0.1   0.0   0.0   0.1   1.3   1.8   6.2 |   24.6
    >= 0.50         |   1.1   2.7   1.3   0.9   0.2   0.0   0.0   0.0   0.0   0.6   1.0   4.2 |   12.0
    >= 1.00         |   0.4   0.6   0.1   0.0   0.0   0.0   0.0   0.0   0.0   0.1   0.4   1.0 |    2.7
                    |                                                                         |
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                    |                                                                         |
WIND (MPH)          |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Daily Avg Wind Speed|   6.4   7.7   8.6  10.2  10.2  10.0   9.8   9.1   8.0   7.0   5.9   7.1 |    8.3
Daily Avg Max 2-Min |  16.2  18.3  19.8  21.5  20.3  20.2  19.3  18.8  18.0  16.9  15.5  17.4 |   18.5
Daily Avg Peak Gust |  19.2  21.7  23.0  25.1  23.9  23.3  22.4  21.7  20.8  20.0  18.7  20.9 |   21.7
                    |                                                                         |
Maximum Daily Avg   |  22.4  24.8  19.8  20.8  20.8  19.4  15.6  14.3  21.3  17.6  23.3  21.9 |   24.8
                    |                                                                         |
Maximum 2-Minute Avg|    43    45    40    41    35    32    28    31    39    52    46    44 |     52
                    |                                                                         |
Date of Max 2min-Day|    04    22    07    14    28    05    26    19    19    22    24    14 |
               -Year|  2008  2002  2002  2002  2004  2007  2000  2000  2007  2000  2001  2002 |
                    |                                                                         |
Maximum Peak Gust   |    62    51    46    48    38    37    33    35    48    62    55    51 |     62
                    |                                                                         |
Date of Max Gust-Day|    04    22    14    14    02    05    23    19    19    22    07    14 |
               -Year|  2008  2002  2005  2002  2001  2007  2007  2000  2007  2000  2002  2002 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
   Peak Gust >=30   |   3.6   5.7   5.5   6.3   3.1   1.7   0.6   0.2   0.7   1.6   2.0   5.1 |   36.0
   Peak Gust >=40   |   0.5   1.4   0.7   1.0   0.0   0.0   0.0   0.0   0.1   0.3   0.6   1.5 |    6.0
   Peak Gust >=50   |   0.1   0.1   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.1   0.3   0.5 |    1.1
                    |                                                                         |
   Max 2-Minute >=30|   1.4   2.9   1.8   2.5   0.9   0.5   0.0   0.1   0.1   0.2   0.7   0.0 |   11.0
   Max 2-Minute >=40|   0.1   0.3   0.1   0.1   0.0   0.0   0.0   0.0   0.0   0.1   0.3   0.0 |    1.1
                    |                                                                         |
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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.