Maidenhead Climatological Summary

Average monthly temperatures (degC)

-------------------------------------------------------

      Mean  Mean  Mean  Highest Lowest  Highest Lowest
      Max   Min         Monthly Monthly Monthly Monthly
                        Max     Max     Min     Min
-------------------------------------------------------
Jan |  8.4   2.5   5.5  13.2     2.7     9.3    -3.7
Feb |  9.3   2.4   5.9  14.3     3.6     9.1    -4.0
Mar | 12.0   4.0   8.0  18.1     6.4    10.3    -2.7
Apr | 14.6   5.3   9.9  21.7     8.1    11.1    -1.2
May | 18.5   8.6  13.5  26.5    11.9    14.4     2.6 
Jun | 21.2  11.4  16.3  28.5    15.2    16.0     6.2
Jul | 23.3  13.4  18.3  29.7    17.7    17.8     8.8
Aug | 23.2  13.2  18.2  29.9    17.6    17.7     8.1
Sep | 19.6  10.9  15.5  25.3    14.4    15.8     5.1
Oct | 15.3   7.9  11.6  20.4    10.7    13.6     1.0
Nov | 10.9   4.3   7.6  16.0     5.8    11.8    -2.2
Dec |  8.2   2.6   5.4  13.6     1.8    10.2    -4.0
Yr  | 15.4   7.2  11.3  31.6     0.9    18.8    -5.7

Extreme Monthly Temperatures (degC)

---------------------------------------------------------------------
      ----Mean Maximum-----  ----Mean Minimum---  -Warmest- -Coldest-
      High Year  Low  Year  High Year  Low  Year    Month     Month 
                                                       Year      Year
---------------------------------------------------------------------
Jan | 10.5 2007   5.1 1997   4.9 2007   0.1 1997   7.7 2007  2.6 1997
Feb | 12.1 1998   5.3 1991   4.7 1990  -1.3 1991   8.2 1990  2.0 1991
Mar | 14.4 2003   8.6 1996   5.5 1998   1.9 1995   9.5 1997  5.5 1996
Apr | 19.5 2007  11.7 1989   6.9 2007   3.6 1990  13.2 2007  7.8 1989
May | 20.8 1989  15.0 1996  10.2 2008   5.9 1996  15.2 1992 10.5 1996
Jun | 23.8 2006  17.4 1991  12.5 2007   9.4 1991  18.1 2006 13.4 1991
Jul | 28.0 2006  19.7 1988  16.0 2006  11.6 1988  22.0 2006 15.6 1988
Aug | 26.9 1995  21.1 1992  15.6 1997  11.1 1993  20.9 1995 16.1 1993
    |                 1993
Sep | 23.0 2006  17.0 1993  14.1 2006   9.3  var  18.5 2006 13.1 1993
Oct | 17.9 1995  12.3 1992  10.7 2006   4.9 1992  14.3 2006  8.6 1992
Nov | 13.2 1994   8.4 1993   8.3 1994   1.3 1988  10.7 1994  5.3 1993
Dec | 10.1 1994   5.4 1995   5.0 2002   0.7 2001   7.4 1998  3.4 1995
Yr  | 16.3 2003  14.2 1996   8.1 2006   6.3 1996  12.2 2006 10.3 1996

Extreme Monthly Temperatures (degC)

---------------------------------------------------------------------------------------------
      -Highest Maximum----  --Lowest Maximum----  -Highest Minimum----  --Lowest Minimum----
      High Year  Low  Year  High Year  Low  Year  High Year  Low  Year  High Year  Low  Year
---------------------------------------------------------------------------------------------
Jan | 16.0 2003  10.9 1997   5.2 1990  -0.6 1997  12.3 2008   5.4 1997  -0.8 2005   -7.1 2002
Feb | 18.5 1990  11.3 1993   7.9 2002  -3.4 1991  12.3 2004   6.4 1996  -0.4 1990   -7.5 1991 
Mar | 22.3 1990  14.8 1996  10.0 1997   3.2 1996  12.9 1998   8.7 1995   0.3 1997   -6.1 2006
Apr | 27.3 2003  15.2 1989  10.3 2002   4.0 1989  13.8 2005   8.3 2001   0.8 2004   -3.6 1990
May | 30.2 2005  20.8 1994  14.9 1999   8.9 1994  17.3 1998  11.6 1994   6.1 1999   -0.9 1997
Jun | 33.4 1995  21.6 1991  18.5 2003  12.4 1989  19.5 2005  13.0 1991   8.7 1993    2.7 1991
Jul | 35.1 2006  22.9 1988  21.1 2006  15.3 1988  20.4 2006  14.7 2000  11.6 2006    6.2 1993
Aug | 37.2 2003  25.8 1993  19.5 2004  16.0 1992  20.9 1995  15.4 2007  10.3 2002    5.7 1993
    |                            2006       1999
Sep | 30.5 2006  21.3 2008  17.1 1997   9.6 1993  18.5 2005  14.5 1990   8.3 2006    1.9 2003
    |                            2002
Oct | 25.2 1997  17.3 1992  14.1 2006   7.0 2008  16.5 2005  10.5 1992   6.3 2001   -3.8 1997
Nov | 17.6 1994  14.2 1995   9.1 1994   1.2 1993  14.8 1996   9.9 2000   1.9 1994   -6.3 1989
Dec | 15.0 2007  12.6 1990   4.4 1998  -1.5 1991  12.6 2000   7.7 2004  -0.3 1988   -8.4 1991
    |                 1996
Yr  | 37.2 2003  27.4 1993   3.5 1998  -3.4 1991  20.9 1995  16.9 2007  -4.0 1998   -8.4 1991

Daily Temperature Distribution (degC)

----------------------------------------------------------------------------------------------
      ------------------------------No. of days with -----------------------------------------
      Minimum temp.-   ------Maximum temp------ -Maximum temp.  Maximum temp.   Minimum temp.
          below -5C         25C or more           30C or more     below 0C        15C or more
      Mean High Year  Mean High Year  Low Year  Mean High Year  Mean High Year  Mean High Year
----------------------------------------------------------------------------------------------
Jan |  0.5    3 1992   0      0    -    0    -   0      0    -   0.3    3 1997     0    0    -
Feb |  0.5    6 1991   0      0    -    0    -   0      0    -   0.2    3 1991     0    0    -
Mar |  0.1    1 2001   0      0    -    0    -   0      0    -     0    0    -     0    0    - 
Apr |    0    0    -   0.1    1 2003    0    -   0      0    -     0    0    -     0    0    -
    |                           2007
May |    0    0    -   2.9    9 1992    0    - 0.1      1 2005     0    0    -   0.4    2 1992
Jun |    0    0    -   4.7   11 2006    0    - 0.5      2  var     0    0    -   2.5    6 2005
Jul |    0    0    -   9.7   21 2006    0    - 1.8     12 2006     0    0    -   8.6   19 2006
Aug |    0    0    -   8.2   22 1995    1      1.5     10 1995     0    0    -   8.4   18 1995
Sep |    0    0    -   2.0    7 2003    0    -   0      1 2006     0    0    -   2.6   14 2006
    |                           2006
Oct |    0    0    -   0      1 1997    0    -   0      0    -     0    0    -   0.3    2 1995
Nov |  0.1    1 1988   0      0    -    0    -   0      0    -     0    0    -     0    0    -
    |           1999
Dec |  0.6    4 1991   0      0    -    0    -   0      0    -   0.2    2 1991     0    0    -
Yr  |  1.6   10 1991  28.4 49.0 1989  6.0 1988 4.1     17 1995   0.6    5 1991  22.6   46 2006

Grass Minimum Temperatures (degC)

-----------------------------------------------------------------------------
      -----------Monthly mean------------ -----------Monthly minimum---------
      Average  --Highest--  ---Lowest---- Average  --Highest--  ---Lowest----
                     Year          Year                  Year          Year
-----------------------------------------------------------------------------
Jan | -0.4      1.8  1996    -2.5  2001   -7.1     -4.3  2008    -9.5  1992
    |                2007                                              2003
Feb | -0.6      2.1  1995    -3.3  1991   -7.5     -4.0  1990   -13.9  1991
Mar |  1.0      2.8  1998    -0.9  2003   -6.1     -2.7  1997   -10.2  1989
    |                              2004
Apr |  2.4      4.4  1993    -0.1  1990   -3.9     -0.8  2007    -7.2  1990
May |  6.4      8.3  2008     3.7  1996    0.1      3.9  1999    -3.9  1997
Jun |  9.4     11.1  2007     7.7  1990    3.9      7.0  1993     0.8  1991
Jul | 11.3     13.5  2006     9.8  1988    6.5      9.1  1994     3.8  1990
    |                              1990
Aug | 11.1     13.7  1997     8.9  1993    5.9      8.6  2002     3.3  1993
Sep |  8.5     11.6  2006     5.1  2003    2.8      6.2  2006    -1.5  2003
Oct |  5.4      8.2  2001     1.0  2003   -1.4      2.6  2001    -6.9  1997
Nov |  1.7      6.0  1994    -0.8  1988   -5.0     -1.0  1994   -10.4  1989
Dec |  0.1      2.8  1988    -2.4  2005   -7.2     -3.9  1988   -10.4  2000
    |                2002
Yr  |  4.7      5.8  2006     3.0  2003   -9.0     -7.2  1990   -13.9  1991

Rainfall Averages

----------------------------------------
      Mean Mean Max  Average number of 
                     days with a fall
      Fall    Daily  0.2   1.0   5.0
              Fall   mm    mm    to 
                     or    or    9.9
       mm      mm    more  more  mm 
---------------------------------------
Jan |  60.8    12.0  16.3  11.7   4.4
Feb |  48.4     9.7  13.1  10.3   3.4
Mar |  42.5    10.1  13.3   9.3   3.7
Apr |  52.0    13.5  13.5  10.0   3.4
May |  48.3    13.6  11.6   8.5   3.5
Jun |  46.3    13.9  11.1   8.4   3.1
Jul |  47.9    15.6  11.4   8.1   2.9
Aug |  54.7    17.0  11.2   8.2   3.4
Sep |  56.2    17.8  12.3   8.3   3.5
Oct |  71.7    19.2  14.0  11.1   5.0
Nov |  70.3    16.3  14.8  11.0   5.1
Dec |  63.6    14.1  14.6  10.7   4.8
Yr  | 666.8    35.7 157.5 116.2  46.3

Rainfall Extremes

-------------------------------------------------------------
     Wettest Month   Driest Month-  Wettest 24 hrs in a month
        mm    Year      mm    Year  -Greatest--    ---Least--
                                     mm   Year     mm   Year
-------------------------------------------------------------
Jan |  127.4  1995      12.8  1997   21.4 2001      3.7 1992
Feb |  105.7  1990       3.5  1993   16.8 1995      1.8 1993
Mar |  100.1  2001      10.0  1990   18.2 2005      4.5 1999
Apr |  120.7  2000       2.0  2007   32.1 1991      1.1 2007
May |   97.0  2007       2.1  1990   35.7 2007      1.5 1990
Jun |  113.3  2007      10.2  2006   30.5 1999      3.3 2006
Jul |  142.6  2007       5.3  1994   70.2 2007      2.2 1994
Aug |  135.7  2001       1.0  1995   48.8 1999      0.6 1995
Sep |  124.0  1995       3.2  1997   59.0 1992      1.3 1997
Oct |  157.5  2000      29.6  1991   49.8 2000      7.6 1995
Nov |  166.2  2002      20.5  1988   35.0 2003      5.1 2004
Dec |  148.2  1989      10.5  1988   35.9 1989      5.6 1991
Yr  |  893.6  2000     492.5  1990   70.2 2007     20.2 1990

Rainfall Extremes

------------------------------------------------------------------------
     ---no. of days with--  ---no. of days with--  ---no. of days with--
     ----0.2mm or more----  ----1.0mm or more----  ----5.0mm or more----
     Most Year Least Year   Most Year Least Year   Most Year Least Year
------------------------------------------------------------------------
Jan | 26  1993    7  1997    18   var    4  2000     9  1995    0   var
    |                                       2006        1999
Feb | 20  1995    3  1993    19  1995    2  1993     9  1990    0   var
Mar | 24  1992    3  1993    17  2004    2  2003    12  2004    0  1999
Apr | 24  1998    3  1997    20  2000    1  2007     9  1998    0  1995
    |                2007                                          2007
May | 18  2006    3  1990    15  2006    1  1990     8  2002    0  1990
    |     2007                   2007                              1991
Jun | 21  1998    4  1995    18  1998    2  1996     8  1998    0  2006
    |                1996                               2007
Jul | 19  1988    5  1990    16  1998    2  1994     6  1988    0  1994
    |                1999
Aug | 21  2008    2  1995    18  2008    0  1995     8  1992    0  1994
    |                                                              1995
Sep | 19  1998    3  1997    14  1995    1  1997     8  1995    0  1997
    |     1999                   1999
Oct | 21  2000    8   var    18  2004    6   var    10  2000    2   var  
    |     2001
Nov | 24  2002    9   var    24  2002    5  1988    15  2002    1   var
Dec | 25  1999    8  1991    19  1993    2  1988    10  1989    1   var
Yr  |181  2002  128  2003   143  2002   88  1996    63  1998   31  1990
    |                                                   2002

5cm Earth Temperatures at 0700GMT (degC)

----------------------------------------------------------------------
     ---Monthly mean temperatures-------   -Extremes of 0700GMT value-
     Average  -Warmest--     -Coldest---   -----Maximum   -----Minimum
                     Year          Year    deg C  Year    deg C  Year
----------------------------------------------------------------------
Jan |  4.3      6.3  2007     1.3  1997     10.0  2008     -2.5  2002
Feb |  4.3      6.1  2002     1.9  1991     10.3  2004     -0.3  1991
    |                              1996
Mar |  6.0      7.2  1997     3.9  1996     11.6  1998      0.6  2001
    |                                                            2006
Apr |  8.1     10.1  2007     6.4  1989     13.8  2007      1.5  1996
May | 12.0     13.2  1998     9.2  1996     18.6  1989      5.4  1991
Jun | 15.2     16.7  2003    12.5  1991     20.2  2005      8.9  1989
Jul | 16.7     19.2  2006    14.1  1988     23.3  2006     11.9  1988
    |                                                            1990
Aug | 16.4     19.2  1995    14.7  1993     22.7  1995     11.4  1989
Sep | 13.7     16.3  2006    12.4  1993     19.7  2005      7.6  1988
Oct | 10.4     13.0  2006     7.9  1992     15.6  2006      1.6  1997
Nov |  6.9      9.8  1994     4.3  1988     13.5  1996      0.4  1988
Dec |  4.8      6.6  2006     3.2  1996     13.9  2001     -1.0  1995
Yr  |  9.9     10.7  2006     8.8  1996     23.3  2006     -2.5  2002

10cm Earth Temperatures at 0700GMT (degC)

----------------------------------------------------------------------
     ---Monthly mean temperatures-------   -Extremes of 0700GMT value-
     Average  -Warmest--     -Coldest---   -----Maximum   -----Minimum
                     Year          Year    deg C  Year    deg C  Year
----------------------------------------------------------------------
Jan |  4.2      6.4  2007     1.1  1997     10.0  2007     -2.0  2002
Feb |  4.3      6.1  2002     1.9  1991      9.9  2004     -0.1  1991
    |                              1996
Mar |  6.0      7.4  1997     3.9  1996     11.4  1998      0.3  1995
Apr |  8.3     10.5  2007     6.9  1989     14.1  2007      2.1  1996
May | 12.2     13.5  1998     9.4  1996     18.4  1989      5.9  1991
Jun | 15.4     17.0  2003    12.6  1991     20.5  2005      9.9  1991
Jul | 17.1     19.7  2006    14.6  1988     22.9  2006     12.1  1990
Aug | 17.0     19.9  1995    15.3  1993     22.9  1995     12.5  1993
Sep | 14.2     16.8  2006    12.8  1993     19.9  2005      8.8  1995
Oct | 10.8     13.4  2006     8.3  1992     15.8  2006      2.4  1997
Nov |  7.0     10.0  1994     4.6  1988     13.4  2005      0.6  1988
Dec |  4.8      6.7  2006     3.1  1996     11.1  2001     -0.6  1995
Yr  | 10.1     10.8  2006     9.1  1996     22.9  1995     -2.0  2002
    |                                             2006

20cm Earth Temperatures at 0700GMT (degC)

----------------------------------------------------------------------
     ---Monthly mean temperatures-------   -Extremes of 0700GMT value-
     Average  -Warmest--     -Coldest---   -----Maximum   -----Minimum
                     Year          Year    deg C  Year    deg C  Year
----------------------------------------------------------------------
Jan |  5.0      7.0  2007     2.0  1997      9.9  2007      0.2  1997
Feb |  5.2      7.0  2002     2.7  1991      9.6  2004      0.8  1991
Mar |  7.0      8.4  1997     5.0  1996     11.1  1998      2.2  2001
    |                                                            2006
Apr |  9.4     11.7  2007     8.2  1989     14.1  2007      4.1  1996
May | 13.2     14.6  1989    10.7  1996     18.9  1989      7.4  1991
Jun | 16.3     18.0  2003    13.3  1991     21.0  2005     11.0  2006
Jul | 18.1     20.5  2006    15.3  1988     23.8  1989     14.0  1990
Aug | 18.1     21.4  1995    16.4  1988     23.6  1995     14.0  1993
Sep | 15.4     17.4  2006    13.9  1993     19.4  2005     11.1  1993
Oct | 11.8     14.3  2006     9.7  1992     16.5  2006      4.8  2008
Nov |  8.0     10.6  1994     6.0  1988     13.7  2005      2.5  1993
Dec |  5.7      7.3  2006     4.0  1996     13.1  1996      1.0  1995
Yr  | 11.1     11.7  2006    10.2  1996     23.8  1989      0.2  1997

30cm Earth Temperatures at 0700GMT (degC)

----------------------------------------------------------------------
     ---Monthly mean temperatures-------   -Extremes of 0700GMT value-
     Average  -Warmest--     -Coldest---   -----Maximum   -----Minimum
                     Year          Year    deg C  Year    deg C  Year
----------------------------------------------------------------------
Jan |  5.7      7.6  2007     2.7  1997      9.4  2007      1.5  1997
Feb |  5.8      7.6  2002     3.1  1991      9.1  2004      1.5  1991
Mar |  7.4      8.6  1997     5.5  2006     10.3  1998      3.2  2005
Apr |  9.7     11.6  2007     8.7  1994     14.0  2007      5.6  1996
    |                              2000
May | 13.2     14.4  1998    10.8  1991     17.5  1998      8.1  1991
Jun | 16.2     17.8  2003    13.1  1991     20.4  2005     11.8  1991
Jul | 18.0     20.2  2006    15.5  1988     22.2  2006     14.7  1988
    |                                                            1997
Aug | 18.4     21.6  1995    17.0  1993     22.9  1995     15.3  1988
Sep | 16.0     17.8  2006    14.5  1993     19.4  2005     12.2  1993
Oct | 12.6     14.9  2006    10.8  1993     16.9  2006      7.3  1997
Nov |  8.9     11.0  1994     7.3  1988     14.0  2005      4.3  1993
Dec |  6.5      8.0  2006     4.9  1996     10.2  2006      2.5  1995
Yr  | 11.5     12.1  1995    10.6  1991     22.9  1995      1.5  1991
    |                2006                                        1997

50cm Earth Temperatures at 0700GMT (degC)

----------------------------------------------------------------------
     ---Monthly mean temperatures-------   -Extremes of 0700GMT value-
     Average  -Warmest--     -Coldest---   -----Maximum   -----Minimum
                     Year          Year    deg C  Year    deg C  Year
----------------------------------------------------------------------
Jan |  5.8      7.8  2007     2.8  1997      9.2  2007      1.7  1997
Feb |  5.7      7.4  2002     3.2  1991      8.4  2002      1.9  1991
Mar |  7.1      8.2  1997     5.3  1996      9.6  1990      3.7  2001
    |                              2006
Apr |  9.2     10.9  2007     8.1  1996     12.8  2007      5.5  1996
May | 12.4     13.5  2007    10.2  1991     16.0  2001      8.1  1991
Jun | 15.4     16.7  2003    12.5  1991     18.9  2005     11.4  1991
Jul | 17.3     19.4  2006    15.3  1988     21.3  2006     14.2  1991
Aug | 18.0     21.1  1995    16.5  1988     22.0  1995     15.2  1988
Sep | 16.0     17.8  2006    14.5  1993     19.2  1995     12.3  1993
Oct | 12.9     15.0  2006    11.0  1993     16.9  2006      8.4  1992
Nov |  9.3     11.0  1994     7.7  1993     14.0  2005      5.0  1993
Dec |  6.8      8.3  2006     5.3  1996     10.3  1994      3.2  1995
    |                                                            1996
Yr  | 11.3     11.9  2005    10.4  1991     22.0  1995      1.7  1997
    |                2006          1996

100cm Earth Temperatures at 0700GMT (degC)

----------------------------------------------------------------------
     ---Monthly mean temperatures-------   -Extremes of 0700GMT value-
     Average  -Warmest--     -Coldest---   -----Maximum   -----Minimum
                     Year          Year    deg C  Year    deg C  Year
----------------------------------------------------------------------
Jan |  7.0      8.7  2007     4.5  1997      9.2  2007      3.9  1997
Feb |  6.6      7.9  2002     4.8  1991      8.4  2002      4.0  1991
Mar |  7.4      8.6  2007     5.8  1996      9.2  1990      5.2  2001
Apr |  9.0     10.3  2007     7.7  1996     12.0  2007      6.3  1996
May | 11.5     12.9  2007     9.8  1991     14.1  1992      8.5  1989
    |                                                            1991
Jun | 14.0     15.0  2003    11.9  1991     16.4  2003     11.2  1991
Jul | 16.0     17.4  2006    14.6  1988     19.1  2006     13.0  1991
Aug | 17.1     19.1  1995    15.7  1988     19.7  1995     14.8  1988
Sep | 15.9     17.1  2006    14.7  1993     18.5  1995     13.4  1993
Oct | 13.7     15.5  2006    12.1  1993     16.9  2006     10.3  1992
Nov | 10.7     11.9  2005     9.3  1993     14.4  2006      7.1  1993
    |                2006
Dec |  8.3      9.7  2006     7.0  1996     11.3  1994      5.4  1996
Yr  | 11.4     12.0  2007    10.6  1996     19.7  1995      3.9  1997

Number of days with certain types of weather

-----------------------------------------------------------------------------------------
      -Snow falling-   --Snow lying--  Hail/Ice Pellets  ------Hail-----  -Ice Pellets--
      Mean  Highest-   Mean  Highest-  Mean  Highest---  Mean  Highest--  Mean  Highest-
                Year             Year            Year              Year             Year
-----------------------------------------------------------------------------------------
Jan |  1.7   4   var    0.3   2  2003   0.4   2  1998     0.2   1   var    0.2   1   var
Feb |  2.9   8   var    1.2   9  1991   0.6   3  2002     0.3   1   var    0.4   3  2002
Mar |  1.8   5   var    0.2   1   var   1.2   7  1995     0.4   3  1995    0.9   4  1995
    |                                                                               2004
Apr |  0.8   4  2000    0.1   1  2008   1.3   4   var     0.5   3  1991    0.7   3   var
May |  0.1   1  1997      0   0     -   0.6   2   var     0.4   2  1997    0.2   1   var
Jun |    0   0     -      0   0     -   0.1   1  1991     0.1   1  1991      0   0     -
Jul |    0   0     -      0   0     -   0.1   1  1996       0   1  2007      0   1  1996
    |                                            2007
Aug |    0   0     -      0   0     -   0.1   1   var       0   1  2005    0.1   1  1991
    |                                                                               1996
Sep |    0   0     -      0   0     -   0.2   1   var     0.1   1  1995    0.1   1  1990
    |                                                                               1993
    |                                                              1998
Oct |  0.1   2  2008      0   0     -   0.1   2  1992       0   0     -    0.1   2  1992
Nov |  0.4   3  1993      0   0     -   0.3   1   var     0.1   1  1997    0.2   1   var
    |                                                              2001
Dec |  1.7   6  1995    0.5   4  2000   0.5   2  1989     0.1   1   var    0.4   1   var
    |                                            1994
Yr  |  9.5  21  1996    2.2   9  1991   5.5  14  1995     2.2   5  1991    3.3   9  1995
    |                                                              1995
Snow lying: defined as a ground cover of 50 per cent or more at 0900GMT

Hail only: defined as hail of diameter 5mm or more

Ice pellets only: includes snow pellets and hail of diameter less than 5mm

Number of days with certain types of weather

------------------------------------------------------
      ----Thunder---   Fog at 09h GMT  -----Gale------
      Mean  Highest-   Mean  Highest-  Mean  Highest--
                Year             Year            Year
------------------------------------------------------
Jan |  0.4   2  1995    1.7   5  1997   0.2   1   var
Feb |  0.4   2  1995    1.7   5   var   0.2   4  1990
Mar |  0.4   2  1995    0.5   4  1997   0.1   1  1995
Apr |  1.4   7  1998    0.1   1  1990     0   0     -
May |  1.8   5  2001      0   0     -     0   0     -
Jun |  1.7   4  2003      0   0     -     0   0     -
    |           2007
Jul |  2.0   5  1995      0   0     -     0   0     -
    |           2007
Aug |  2.2   6  2004      0   1  2008     0   0     -
Sep |  1.4   4   var    0.2   1   var     0   0     -
Oct |  0.7   3  1993    0.6   2   var   0.1   2  1989
    |           2001
Nov |  0.3   2  2006    1.7   7  2002     0   0     -
Dec |  0.2   3  1989    1.7   4  1991   0.1   2  1993
    |                            2006
Yr  | 13.0  18   var    8.1  15  1997   0.6   5  1990
Fog at 09GMT: defined as visibility below 1000 metres.

Gale: a wind speed averaging 34 knots for at least 10 minutes.

Frost

--------------------------------------------------------------------
     -----------Air frost----------   --------Ground frost----------
      Mean    Most days   Least days  Mean    Most days   Least days
      no      in a month  in a month  no      in a month  in a month
      of          Year        Year    of           Year       Year  
      days                            days                          
--------------------------------------------------------------------
Jan |  7.7    17  1997     2  2008     17.2    24  1997    8  1996
Feb |  8.0    18  1991     1  1990     16.3    23  1991    6  1995
    |             1996                             1996 
Mar |  4.3    12  1995     0  1997     13.4    19  2003    7  1992
Apr |  2.0     6  2008     0   var      7.4    16  1990    1  2007
May |  0.1     1  1997     0   var      1.0     8  1996    0   var
Jun |    0     0     -     0     -        0     0     -    0     -
Jul |    0     0     -     0     -        0     0     -    0     -
Aug |    0     0     -     0     -        0     0     -    0     -
Sep |    0     0     -     0     -      0.1     3  2003    0     -
Oct |  1.0     5  1997     0   var      3.3    11  1992    0   var
    |                                              2003
Nov |  4.7    13  1988     0  1994     10.6    19  1988    2  1994
    |                         2002
Dec |  8.6    18  2001     1  2002     16.3    26  2005    5  2002
Yr  | 36.1    57  1996    15  2002     85.4   120  2003   59  2002

Winter data

Days with snow falling                       - most:     21 1995-1996
                                               least:     2 1989-1990
                                                          2 1991-1992
Date of first winter snow                    - earliest: 28 Oct 2008
                                               average:  17 December
                                               latest:   18 Feb 1991
Date of last winter snow                     - earliest: 14 Feb 1991
                                               average:  26 March
                                               latest:    6 May 1997
Mornings (09GMT) with 50 per cent snow cover - most:     10 1990-1991
                                               least:     0 various
Days with air frost                          - most:     52 1995-1996
                                                         52 2005-2006
                                               least:    20 1989-1990
Date of first winter air frost               - earliest: 16 Oct 1992
                                                         16 Oct 1993
                                               average:   8 November
                                               latest:   16 Dec 1994
Date of last winter air frost                - earliest: 22 Mar 2007
                                               average:  10 April
                                               latest:    7 May 1997
Days with ground frost                       - most:    109 2003-2004
                                               least:    61 2006-2007
Date of first winter ground frost            - earliest: 24 Sep 2003
                                               average:  20 October
                                               latest:   13 Nov 2004
Date of last winter ground frost             - earliest:  5 Apr 2007
                                               average:  26 April
                                               latest:   20 May 1996

Sunshine Averages

----------------------------------------------------------------
      Monthly  Mean     --Average number of days with sunshine--
       mean    maximum         (hours) in the range         
       sun     duration 0     12.1 
      hr/day     hrs          or   
                              more 
----------------------------------------------------------------
Jan |  1.90      6.7   11.6      0
Feb |  2.87      8.4    7.6      0
Mar |  3.69     10.4    6.1      0
Apr |  5.23     11.9    3.2    1.1
May |  6.42     14.0    2.7    4.7
Jun |  6.42     14.2    1.6    4.5
Jul |  6.45     14.1    1.2    4.5
Aug |  6.41     12.8    1.0    2.9
Sep |  4.69     10.9    2.5      0
Oct |  3.47      9.3    5.7      0
Nov |  2.27      7.6    9.3      0
Dec |  1.63      6.2   13.1      0
Yr  |  4.30     14.8   65.6   17.8

Sunshine extremes

-----------------------------------------------------------------------------------------------
      Sunniest    Dullest    --Greatest total in--  No. of sunless days-   --No. of days with--
        month       month            24 hours                               12.1h sunshine
       hr/day      hr/day    -Highest-  --Lowest-   -Highest-  --Lowest-   -Highest-  --Lowest-
           Year        Year   hrs Year   hrs Year   days Year  days Year   days Year  days Year
-----------------------------------------------------------------------------------------------
Jan | 2.93 2003   0.63 1996   7.8 2004   3.3 1996    18  1996    6  2003     0     -    0     -
    |                             2008
Feb | 5.02 2008   1.74 1991   9.5 1996   6.9 1997    13  1993    3  1998     0     -    0     -
    |                             2001
Mar | 5.90 2007   1.80 1992  11.7 2007   7.5 1992    13  1996    1  1995     0     -    0     -
Apr | 8.17 2007   2.87 1998  13.7 2007   9.2 1995     6  2000    0  1990     7  2007    0   var
May | 9.86 1989   3.91 1991  14.9  var  11.6 2000     8  1994    0   var    15  1989    0  2000
Jun | 8.43 2006   4.15 1990  15.5 1993  10.8 1998     3   var    0   var     9  1996    0   var
Jul | 9.55 2006   4.41 1992  15.3 1990  11.5 1998     4  1992    0   var    13  2006    0  1998
Aug | 8.66 1995   3.87 2008  14.4 1998  10.5 1994     3   var    0   var     9  2007    0   var
Sep | 6.36 2003   2.68 1993  12.3 1988   8.2 1995     7  1994    0   var     1  1988    0   var
Oct | 5.10 1997   2.39 1991  10.1 1988   8.1 1989    12  1991    2  2003     0     -    0     -
Nov | 3.43 2006   1.17 1994   9.2 2006   6.3 2004    17  1994    4  2007     0     -    0     -
Dec | 2.72 2001   0.85 1989   7.1 1997   4.4 1989    19  1995    3  2005     0     -    0     -
Yr  | 5.22 2003   3.63 1992  15.5 1993  13.4 1991    81  1994   50  1990    38  1989    6  1991
    |                                                               2005                   2000

Monthly mean wind speed at 07GMT (knots)

----------------------------------------
     ----Monthly mean wind speed--------
     Average  -Windiest--    -Calmest---
                     Year          Year
----------------------------------------
Jan |   5.8     8.5  1990     3.4  1997
Feb |   5.3    10.9  1990     2.5  1998
Mar |   5.2     7.2  1989     3.3  1999
Apr |   4.9     7.7  1991     2.8  1996
May |   5.3     7.6  1991     3.4  2004
Jun |   5.0     7.2  1990     3.2  2007
    |                1991
Jul |   4.9     7.9  1988     3.0  1997
Aug |   4.2     6.6  1992     2.9  1997
Sep |   3.9     7.1  1989     2.1  2002
Oct |   4.7     7.2  1990     2.6  1994
Nov |   4.6     7.3  1990     2.2  1998
Dec |   5.2     7.0  1990     3.8  2008
Yr  |   4.9     6.7  1990     4.0  1997

Monthly mean cloud cover at 07GMT (oktas, eighths)

----------------------------------------
     ----Monthly mean cloud cover-------
     Average  -Cloudiest-    -Clearest-
                     Year          Year
----------------------------------------
Jan |   6.0     7.4  1997     5.2  2001
Feb |   5.8     6.8  2005     4.8  2008
Mar |   5.7     6.9  1996     3.7  1997
Apr |   5.5     6.8  1993     3.6  1990
    |                1998
May |   5.3     6.3  2002     3.3  1989
Jun |   5.5     7.0  1995     4.5  1989
    |                              1996
Jul |   5.5     6.5  1992     3.8  1990
Aug |   5.1     6.2  2002     3.5  1989
Sep |   5.6     6.5   var     4.6  2003
Oct |   5.5     6.7  2005     4.5  1999
Nov |   5.7     6.7  1994     4.1  1989
Dec |   6.0     7.8  1989     4.6  1999
Yr  |   5.6     6.1  1991     4.8  1990

Evaporation (Piche) (ml)

-------------------------------------------------------
     ---Monthly total evaporation------   -Greatest---
     Average  -Highest---     -Lowest--   -Daily value
                     Year          Year       ml  Year
-------------------------------------------------------
Jan | 24.8     32.6  2007    15.0  1997      2.6  2008
Feb | 30.5     57.9  2000    18.7  1993      3.1  2002
Mar | 43.5     54.6  2003    31.0  2001      3.4  2003
Apr | 55.2     76.8  2003    40.1  2000      5.6  2003
May | 66.4     79.7  1995    53.9  2000      5.5  1997
    |                                             2007
Jun | 71.1     91.2  1996    50.9  1998      6.6  1997
Jul | 76.4    110.9  2006    59.2  2000      7.2  2006
Aug | 72.3    136.2  1995    48.8  2008      7.5  1995
Sep | 48.8     66.0  2003    34.8  2000      4.6  2003
Oct | 35.2     46.2  2003    27.5  2007      3.1  1992
Nov | 22.5     32.0  1999    17.4  1997      2.6  2003
Dec | 21.4     27.4  1993    11.1  1995      2.7  1993
Yr  |569.0    677.3  2003   515.6  2001      7.5  1995

Monthly mean relative humidity at 09GMT (%)

----------------------------------------
     -Monthly mean relative humidity---
     Average  - Highest--    --Lowest--
                     Year          Year
----------------------------------------
Jan |  90.0      93  1994      86  1991
    |                1996          2008
Feb |  88.4      93  2007      84  1990
    |                              2002
Mar |  84.4      90  1992      78  2008     
Apr |  77.4      86  1998      71  2002
    |                              2003
May |  73.3      82  2003      66  1996
Jun |  71.8      81  1998      62  2001
Jul |  72.3      80  1991      63  1990
    |                1992
Aug |  74.7      82  1992      64  1995
Sep |  81.7      89  1993      74  1989
Oct |  88.0      92  2005      80  1990
Nov |  91.3      95  1994      86  1999
Dec |  91.2      94  1992      88   var
    |                1994
Yr  |  81.9      84   var      77  1990

Frost and rainfall duration (hours)

------------------------------------------------------------------------------
     ---Monthly total rain duration----    ---Monthly total frost duration---
     Average  -Highest---     -Lowest--    Average  -Highest---     -Lowest--
                     Year          Year                    Year          Year 
------------------------------------------------------------------------------
Jan | 58.5    102.0  1995    19.8  1997     57.3    193.8  1997     4.2  2008
Feb | 48.8     81.5  2007     6.4  1998     56.8    232.0  1991     1.9  1990   
Mar | 46.2     87.5  2001    10.2  1990     17.3     47.2  2006       0  1997
Apr | 45.5    104.3  2000     2.7  2007      6.7     23.2  2003       0   var
May | 36.6     82.1  2007     2.3  1990      0.1      2.0  1997       0   var
Jun | 31.4     70.3  1991     4.1  1996        0        0     -       0     -
Jul | 30.2     59.5  1988     6.3  1999        0        0     -       0     -
Aug | 31.7     73.8  2008     3.3  1995        0        0     -       0     -
Sep | 38.1     79.9  1998     8.5  1997        0        0     -       0     -
Oct | 51.6     90.0  1998    24.2  2007      5.1     37.7  1997       0   var
Nov | 59.4    109.5  2002    25.7  1989     25.5    102.1  1993       0   var
Dec | 55.5     91.1  2002    13.0  1991     63.2    160.7  1991     0.4  1988
Yr  |536.3    651.3  1998   413.1  1990    232.2    471.3  1991    98.2  2002

Longest absolute droughts

1989      12 Nov -  7 Dec          26 days   trace
1990       7 Jul - 28 Jul          22 days   trace
1995      28 Jul - 22 Aug          26 days   trace
1997      26 Mar - 17 Apr          23 days   trace
2002      21 Mar - 16 Apr          27 days   trace
2003       9 Mar - 31 Mar          23 days   trace
2007      31 Mar - 21 Apr          22 days   trace

Longest sunless spells

2006     18 Dec - 27 Dec           10 days

Longest frost spells (minimum temperature below 0.0 degC)

1991       1 Feb - 16 Feb          16 days
1991       6 Dec - 16 Dec          11 days
1996      24 Dec -  5 Jan          13 days

Longest ice spells (maximum temperature below 0.0degC)

1991      2 Feb -  9 Feb          3 days
1996     25 Jan - 26 Jan          2 days
1997      7 Jan -  8 Jan          2 days

Longest hot spells (maximum temperature 25.0degC or above)

1989    15 Jul - 29 Jul          15 days
1995    28 Jul -  6 Aug          10 days
1995     9 Aug - 22 Aug          14 days
1997     6 Aug - 16 Aug          11 days
2003     2 Aug - 14 Aug          13 days
2004    28 Jul -  8 Aug          12 days
2006    15 Jul - 30 Jul          16 days

Longest sunny spells (10 hours of sunshine each day)

1990      27 Apr -  6 May          10 days   128.7hrs
1997      24 May -  2 Jun          10 days   132.9hrs

Longest snowy spells

1991      SL    8 Feb        9cm snow lying
1991      SL    9 Feb        7cm snow lying
1991      SL   10 Feb        7cm snow lying
2007      SL    8 Feb        9cm snow lying
SL - snow lying to a depth of more than 5cm at 09GMT

Longest wet spells (1mm or more each day)

1989      11 Dec - 20 Dec          10 days  129.8mm
1997      18 Jun - 28 Jun          11 days   55.4mm
1997/8    28 Dec -  7 Jan          10 days   58.3mm       
1998       1 Apr - 10 Apr          10 days   60.3mm
2000      10 Apr - 21 Apr          12 days   56.0mm
2002       5 Nov - 17 Nov          13 days   98.2mm

Hot days (maximum temperature of 35degC or more)

10 Aug 2003  37.2
 3 Aug 1990  35.3
19 Jul 2006  35.1
 6 Aug 2003  35.0

Cold days (maximum temperature of -3degC or below)

 7 Feb 1991  -3.4

Cold nights (minimum temperature of -10degC or below)

None

Warm nights (minimum temperature of 20.0degC or more)

21 Jun 1988  20.9
 2 Aug 1995  20.4
 9 Aug 2004  20.4
22 Jul 2006  20.0

Wet days (rainfall total of 50mm or more)

19 Jul 2007  70.2
22 Sep 1992  59.0

Sunny days (15.5 hours of sunshine or more)

27 Jun 1993  15.5

Last updated 1 January 2009. This page is maintained by Roger Brugge r.bruggeREMOVE@reading.ac.uk

© 2009 Roger Brugge