STATION:  HAYWARD EXECUTIVE AIRPORT (KHWD), CA

CLIMATOLOGICAL SUMMARY.  Period of Record: Sep 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        |  57.1  59.9  63.3  64.4  68.5  72.0  74.4  74.6  75.2  71.1  63.5  57.9 |   66.8
Avg Min Temp        |  42.8  45.1  47.2  48.9  52.8  55.4  57.8  58.3  57.3  53.3  48.1  43.1 |   50.8
Avg Temperature     |  50.0  52.5  55.2  56.7  60.6  63.7  66.1  66.5  66.2  62.2  55.8  50.5 |   58.8
                    |                                                                         |
Extremes:           |                                                                         |
    Extreme Max Temp|    70    77    87    91    99   104   105    96    98    92    85    74 |    105
                    |                                                                         |
    Date of Ext-Day |    06    27    16    26    15    14    22    09    04    14    14    19 |
               -Year|  2003  2002  2004  2004  2008  2000  2006  2002  2008  2001  2008  1999 |
                    |                                                                         |
    Extreme Min Temp|    28    35    36    36    43    48    53    54    47    43    35    27 |     27
                    |                                                                         |
    Date of Ext-Day |    15    10    08    09    01    07    04    07    29    31    23    23 |
               -Year|  2007  1999  2002  1999  2008  2008  1999  2002  2007  2002  2003  1998 |
                    |                                                                         |
Heating Degree Days |   467   354   307   257   158    84    33    21    37   111   277   450 |   2554
Cooling Degree Days |     0     0     4     7    22    44    67    67    74    24     1     0 |    309
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Max Temp >= 90  |   0.0   0.0   0.0   0.1   0.6   1.2   1.5   1.4   2.6   0.3   0.0   0.0 |    7.7
    Max Temp >= 75  |   0.0   0.2   2.6   3.3   5.2   8.4  13.5  14.2  12.3   9.5   1.1   0.0 |   70.4
    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  |   0.8   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.5 |    1.3
    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  |  41.4  43.4  45.0  45.6  49.8  51.9  54.4  55.4  53.5  49.6  46.6  41.4 |   48.2
Avg Wet Bulb Temp   |  45.4  47.5  49.8  50.6  54.1  56.2  58.2  59.2  58.2  54.8  51.0  46.0 |   52.6
                    |                                                                         |
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                    |                                                                         |
Avg Sea Level Pres  | 30.18 30.11 30.11 30.07 30.02 29.98 29.98 29.97 29.95 30.03 30.13 30.18 |  30.06
(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   |   0.3   0.9   0.6   0.6   0.7   0.4   2.0   1.1   1.1   1.3   1.0   1.3 |   11.2
    Heavy Fog       |   1.4   0.9   0.3   0.1   0.0   0.0   0.0   0.1   0.1   0.4   0.9   1.2 |    5.4
    Fog             |  17.1  12.3   8.1   6.3   3.5   1.7   1.3   3.9   5.4   6.3  11.5  13.5 |   90.8
    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     |  2.72  3.41  2.01  1.38  0.47  0.09  0.00  0.02  0.13  0.92  1.47  3.56 |  16.19
                    |                                                                         |
Maximum Daily       |  1.96  2.12  0.75  0.86  0.48  0.24  0.00  0.11  0.31  1.48  1.23  1.60 |   2.12
                    |                                                                         |
    Date of Ext-Day |    24    13    22    12    08    08          06    01    19    01    29 |
               -Year|  2000  2000  2005  2003  2005  2005        1999  2000  2004  2008  2003 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    >= 0.01         |  12.2  12.2   9.4   7.1   3.1   0.8   0.0   0.6   1.3   3.8   8.8  11.5 |   70.9
    >= 0.10         |   6.0   7.8   6.1   4.2   1.3   0.4   0.0   0.1   0.6   2.3   4.0   7.2 |   39.9
    >= 0.25         |   3.3   5.1   3.4   2.2   1.0   0.0   0.0   0.0   0.1   1.2   2.0   4.8 |   23.1
    >= 0.50         |   1.2   2.2   0.8   0.8   0.0   0.0   0.0   0.0   0.0   0.5   0.8   2.7 |    9.0
    >= 1.00         |   0.5   0.5   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.2   0.2   0.6 |    2.0
                    |                                                                         |
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                    |                                                                         |
WIND (MPH)          |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Daily Avg Wind Speed|   5.5   6.4   7.3   8.7   8.8   8.7   8.2   7.7   6.7   5.7   5.2   5.7 |    7.1
Daily Avg Max 2-Min |  14.1  16.5  18.2  19.8  19.3  18.7  17.0  17.0  16.4  15.4  13.8  14.6 |   16.7
Daily Avg Peak Gust |  17.3  19.9  21.9  24.1  23.1  22.3  20.4  20.2  19.5  18.3  16.8  18.3 |   20.2
                    |                                                                         |
Maximum Daily Avg   |  17.0  18.4  15.9  18.3  17.3  16.4  13.0  12.6  15.2  16.0  19.2  19.4 |   19.4
                    |                                                                         |
Maximum 2-Minute Avg|    36    37    37    36    30    33    24    24    28    39    38    37 |     39
                    |                                                                         |
Date of Max 2min-Day|    01    03    07    14    14    06    19    30    19    22    24    14 |
               -Year|  2006  2000  2002  2002  1999  2005  2001  1999  2007  2000  2001  2002 |
                    |                                                                         |
Maximum Peak Gust   |    43    44    45    49    48    40    36    36    37    54    48    63 |     63
                    |                                                                         |
Date of Max Gust-Day|    01    03    04    29    22    06    22    17    19    22    24    25 |
               -Year|  2006  2000  2001  2008  2008  2005  2007  2008  2007  2000  2001  2008 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
   Peak Gust >=30   |   2.3   3.5   3.4   4.4   2.6   1.1   0.3   0.1   0.2   0.8   1.7   3.5 |   23.9
   Peak Gust >=40   |   0.3   0.3   0.2   0.4   0.1   0.1   0.0   0.0   0.0   0.2   0.2   0.6 |    2.4
   Peak Gust >=50   |   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.0   0.1   0.0   0.1 |    0.2
                    |                                                                         |
   Max 2-Minute >=30|   0.5   0.9   0.3   0.7   0.3   0.2   0.0   0.0   0.0   0.2   0.4   0.0 |    3.5
   Max 2-Minute >=40|   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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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.