STATION:  HAWTHORNE-NRTHORP FLD/HATHRN MUNI AP (KHHR), 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        |  67.1  66.8  67.8  68.5  71.4  73.6  77.4  77.7  76.9  75.1  71.2  67.0 |   71.7
Avg Min Temp        |  49.2  50.3  52.8  54.3  58.8  61.8  65.0  64.9  63.1  59.5  53.8  48.6 |   56.8
Avg Temperature     |  58.2  58.6  60.3  61.4  65.1  67.7  71.2  71.3  70.0  67.3  62.5  57.8 |   64.3
                    |                                                                         |
Extremes:           |                                                                         |
    Extreme Max Temp|    91    90    92   101    98    95    92    90   101    99    94    85 |    101
                    |                                                                         |
    Date of Ext-Day |    31    21    08    27    03    27    20    31    30    20    07    11 |
               -Year|  2003  2002  2004  2008  2004  2006  2005  2007  1999  1999  2006  2004 |
                    |                                                                         |
    Extreme Min Temp|    34    38    41    43    51    51    58    60    57    50    41    37 |     34
                    |                                                                         |
    Date of Ext-Day |    14    11    12    04    01    04    01    08    11    30    29    23 |
               -Year|  2007  1999  2006  1999  1999  1999  2005  1999  1999  2000  2004  1998 |
                    |                                                                         |
Heating Degree Days |   222   191   162   131    41     6     0     0     1    28   103   226 |   1110
Cooling Degree Days |    10     9    16    24    44    87   192   195   150    98    28     2 |    855
                    |                                                                         |
Avg Number of Days: |                                                                         |
    Max Temp >= 90  |   0.1   0.1   0.5   0.7   0.7   0.4   0.5   0.1   1.7   2.5   0.5   0.0 |    7.8
    Max Temp >= 75  |   5.5   4.2   4.6   4.4   6.1   9.7  21.5  25.3  17.6  12.3   7.9   5.4 |  124.4
    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  |   0.0   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 <= 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  |  41.5  43.9  46.3  47.6  53.3  57.2  60.5  60.1  58.2  53.0  46.6  40.7 |   50.7
Avg Wet Bulb Temp   |  49.9  51.0  52.7  53.8  58.0  61.1  63.7  64.0  62.3  58.8  54.1  49.1 |   56.5
                    |                                                                         |
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                    |                                                                         |
Avg Sea Level Pres  | 30.10 30.07 30.02 29.99 29.94 29.91 29.92 29.91 29.89 29.95 30.04 30.10 |  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   |   1.5   1.0   0.5   0.3   0.6   0.2   0.4   0.2   0.4   1.2   1.0   1.4 |    8.7
    Heavy Fog       |   2.0   0.9   1.2   0.3   0.4   0.1   0.0   0.4   1.4   2.1   2.6   1.8 |   13.2
    Fog             |  12.7  11.3  11.4   7.2  10.6  11.8  11.1  11.2  12.5  13.5  12.1  12.4 |  137.8
    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     |  2.08  3.22  1.20  0.91  0.24  0.01  0.01  0.00  0.12  0.73  0.75  1.44 |  10.71
                    |                                                                         |
Maximum Daily       |  1.61  2.71  2.66  1.66  0.78  0.12  0.06  0.00  0.60  1.33  1.33  3.81 |   3.81
                    |                                                                         |
    Date of Ext-Day |    10    12    15    11    02    02    28          22    20    08    28 |
               -Year|  2001  2003  2003  1999  2003  1999  2003        2007  2004  1998  2004 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
    >= 0.01         |   7.9   8.1   5.4   3.0   1.0   0.3   0.4   0.0   0.8   2.8   5.8   6.8 |   42.3
    >= 0.10         |   3.6   5.4   2.1   1.8   0.6   0.1   0.0   0.0   0.3   1.4   1.4   2.4 |   19.1
    >= 0.25         |   2.7   3.5   1.3   1.1   0.3   0.0   0.0   0.0   0.2   1.1   1.3   1.5 |   13.0
    >= 0.50         |   1.6   2.4   0.8   0.6   0.2   0.0   0.0   0.0   0.1   0.6   0.6   0.6 |    7.5
    >= 1.00         |   0.5   0.9   0.2   0.1   0.0   0.0   0.0   0.0   0.0   0.1   0.1   0.3 |    2.2
                    |                                                                         |
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                    |                                                                         |
WIND (MPH)          |   Jan   Feb   Mar   Apr   May   Jun   Jul   Aug   Sep   Oct   Nov   Dec |   Year
                    |                                                                         |
Daily Avg Wind Speed|   3.5   4.5   5.2   6.0   5.9   5.9   5.8   5.5   5.0   4.0   3.2   3.1 |    4.8
Daily Avg Max 2-Min |  12.8  14.9  15.7  16.9  15.7  14.8  14.8  14.7  14.6  13.7  12.9  12.6 |   14.5
Daily Avg Peak Gust |  15.8  18.3  19.2  20.8  19.3  18.4  18.0  17.9  17.7  16.4  15.8  15.8 |   17.8
                    |                                                                         |
Maximum Daily Avg   |  14.2  13.6  12.6  12.7  11.1   9.3   9.4   8.2   9.0  10.8  10.0  11.2 |   14.2
                    |                                                                         |
Maximum 2-Minute Avg|    26    29    32    34    25    23    22    22    25    31    32    31 |     34
                    |                                                                         |
Date of Max 2min-Day|    05    13    27    03    09    08    16    04    19    05    24    27 |
               -Year|  2008  2001  2007  1999  2003  2000  2003  2003  2004  2007  2001  2006 |
                    |                                                                         |
Maximum Peak Gust   |    37    38    43    44    31    29    25    26    30    40    43    40 |     44
                    |                                                                         |
Date of Max Gust-Day|    05    13    15    12    09    08    16    26    19    05    21    25 |
               -Year|  2008  2001  2008  2007  2003  2000  2003  2007  2004  2007  1999  2008 |
                    |                                                                         |
Avg Number of Days: |                                                                         |
   Peak Gust >=30   |   0.6   0.9   1.9   1.8   0.6   0.0   0.0   0.0   0.1   0.1   0.6   1.1 |    7.7
   Peak Gust >=40   |   0.0   0.0   0.2   0.2   0.0   0.0   0.0   0.0   0.0   0.1   0.1   0.1 |    0.7
   Peak Gust >=50   |   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
                    |                                                                         |
   Max 2-Minute >=30|   0.0   0.0   0.2   0.3   0.0   0.0   0.0   0.0   0.0   0.1   0.2   0.0 |    0.8
   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.