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graphs CLIMATE-UK.COM'S REVIEW OF THE BRITISH METEOROLOGICAL SCENE
MONTHLY SUMMARY
No. 600 For DECEMBER 2005
HEAVY RAIN EARLY AND LATE, OTHERWISE QUIET AND VERY SUNNY
Text Box: Cyclonic conditions prevailed during the first week and the last three days, otherwise December was a mainly anticyclonic month. Cold weather was confined to a brief northerly outbreak around the 17th and a northeasterly episode between the 26th and 29th. Mean monthly sea-level pressure was 2 to 5 mbar above normal throughout the UK, and the anomalous flow over the country was northeasterly.

A deep depression (central pressure 961mbar at landfall near Plymouth early on the 2nd) tracked across the country from Devon to Northumberland during the 2nd and 3rd, slowly filling, before transferring southwards into the continent over the next few days. The first three days of the month were very unsettled with heavy rain and local thunder, and 79mm of rain fell at Cardinham (Cornwall) in 48 hours. Southerly gales and high spring tides combined to cause coastal flooding along the Channel coast, and the railway line at Dawlish (Devon) was damaged. Following the November cold spell it became milder for a few days, but a rather cold northeasterly flow set in during the 5th and 6th and there was a widespread frost early on the 7th ahead of a further belt of rain.

Strong rises of pressure on the 8th marked the beginning of a long anticyclonic spell. Highest pressure lay over the near continent at first, over the British Isles from the 11th-13th, thence retrogressing to mid-Atlantic and allowing a northerly to develop briefly on 16th-17th. After a frosty start on the 8th, Scotland and Northern Ireland became exceptionally mild with maxima approaching 14C on each of the next three days, and overnight minima of 10C or higher. Much of England and Wales, meantime, was less mild with night frosts and sunny days: Hastings (Sussex) logged 8.0 hours of bright sunshine on the 9th. The settled weather continued for several more days, and on the 12th the barometer reached 1046.9 mbar at Castlederg (Tyrone); a preliminary search indicates that this may have been the highest sea-level pressure in the UK since January 1992, and the highest in December since 1980.  As the anticyclone retreated, a cold front swept southwards on the 16th introducing a short-lived northerly outbreak
Text Box: which brought snow showers to northern and eastern districts and a couple of sharp frosts: Aboyne (Aberdeenshire) recorded -8.8C early on the 18th. Highest pressure returned to France from the 18th-23rd, with a rather mild westerly air-stream covering the UK. Most places stayed dry but cloudy.

An anticyclone developed over the UK on the 24th and 25th, moving to Scandinavia on the 26th and introducing four days of very cold northeasterly winds. Snow showers fell widely in eastern and central districts between the 27th and 29th, and although most falls were slight to moderate, some 30cm of level snow accumulated over the North Downs between Ashford and Dover. Some western areas, meanwhile, remained dry and very sunny, and at St Mawgan (Conrwall) a total of 29 hours of bright sunshine was logged during the four days 25th-28th. The temperature fell to -12.8C at Aviemore (Inverness-shire) overnight 28th/29th, and climbed no higher than -3.9C at Durham during the 29th. Atlantic fronts advanced eastwards across the country on the 30th; snow was heavy for a time in northeast England, but the snowed turned to rain in all areas as temperatures climbed briskly. Highs of 13C were noted in Wales and the West Country.

Mean monthly temperature was close to the long-term average in most parts of the UK - slightly above in Scotland and Northern Ireland, slightly below in southern England where it was the coldest December for four years. Rainfall was below average practically everywhere, with less than half the normal in parts of northern and western Scotland, Cumbria, Yorkshire, Lincolnshire and East Anglia, while at Portland (Dorset) there was no significant rain between the 8th and 28th inclusive. Sunshine totals were near normal in northern and eastern Scotland and in Northern Ireland, but well above average everywhere else, and excesses of 80% occurred locally in southern England, the north Midlands and Yorkshire. Over England and Wales it was the fourth sunniest December on record, after 1886, 1962 and 2001, while November and December were the sunniest such pairing since records began.
                                                                                                                                         
    TEMPERATURE   SUNSHINE   RAINFALL        
                                                                                                                                 
                                                                                                                                 
                                  Highest and lowest totals             Highest and lowest totals        
                                  on record for month    
Maximum fall in 24 hrs
   (beginning 09 h)
        on record for month    
Days with snow or sleet
 
Days with fog
(Vis <220 yards at 09 h)
 
                                                                                         
     
Difference from average
   
Difference from average
 
Highest maximum
   
Lowest minimum
   
No. of days with grass
  minimum below 0C
   
Days of no sunshine
 
Maximum duration
       
First year of record
         
Days of no rainfall
 (0.1 mm or less)
         
First year of record
         
Days with thunder
     
  PLACE  
Mean Maximum
   
Mean minimum
             
No. of air frosts
       
Total for month
                   
Total for month
                   
                               
% of average
                   
% of average
                 
                                                                     
                                   
Highest
   
Lowest
 
Year
             
Highest
   
Lowest
 
Year
       
             
Date
   
Date
         
Date
         
Year
         
Date
         
Year
           
                                                                     
    C     C     C     C           Hrs     Hrs       Hrs     Hrs       mm     mm       mm     mm          
                                                                                                                                         
  *Hampstead   07.5   -0.2   01.7   -0.7   12.1   24   -04.2   18   21   08   02   06.1   19   083   184   1910   086   2001   008   1956   15   19.6   30   042   068   1910   175   1914   10   1933   01   04   00  
  Thorney Island   08.1   -0.5   02.0   -1.7   12.6   16   -04.8   18   19   11   05   07.6   17   097   158   1958   114   2001   037   1966   13   10.6   07   060   083   1941   165   1993   19   1953   01   01   00  
  *Coltishall   06.9   -0.2   02.2   -0.3   10.1   24   -04.8   30   18   07   07   06.4   19   061   122   1979   082   1999   022   2002   08   17.6   30   056   093   1964   120   1965   24   1988   00   06   01  
  *Wittering   06.8   +0.3   02.3   -0.3   10.5   15   -05.3   18   16   08   07   06.5   19   073   145   1950   082   2001   020   1956   16   07.8   30   024   044   1948   130   1978   07   1963   00   05   01  
                                                                     
  Lyneham   06.9   -0.3   02.1   -0.7   11.7   16   -04.4   18   17   09   05   06.5   17   060   120   1952   083   2001   017   1956   20   29.0   01   077   106   1945   159   1959   16   1988   01   03   00  
  Ross-on-Wye   07.9   +0.5   01.4   -2.0   13.0   16   -06.0   29   18   09   10   06.1   11   057   116   1915   078   1948   012   1989   18   30.0   02   070   098   1859   197   1929   11   1991   00   02   00  
  *St Athan   08.4   +0.5   03.6   -0.5   11.5   16   -05.2   29   12   06   07   06.1   19   069   151   1954   072   2001   003   1956   17   27.8   02   114   121   1954   208   1965   31   1988   01   01   00  
  St Mawgan   09.1   -0.2   04.6   -1.0   11.7   19   -03.8   29   08   03   08   07.5   27   080   146   1945   103   2001   027   1988   18   22.0   02   088   076   1944   233   1959   30   1991   01   01   00  
                                                                     
  *Edgbaston   06.7   -0.4   03.2   -0.4   10.5   23   -05.5   29   11   05   03   05.4   17   048   108   1887   090   1891   005   1890   14   15.2   01   049   072   1887   166   1965   10   1926   00   04   00  
  *Valley   08.9   0.0   05.3   -0.1   11.4   01   -03.4   28   08   03   12   06.0   12   044   090   1946   080   1960   025   1998   09   12.6   01   056   061   1941   179   1964   17   1963   00   01   00  
  *Woodford   07.1   +0.3   01.9   -0.4   10.6   10   -08.1   29   14   12   10   05.1   17   045   110   1945   075   2001   016   1947   07   13.2   05   066   083   1942   180   1965   11   1963   00   02   00  
  *Watnall   06.5   0.0   02.9   +0.3   10.1   15   -05.7   29   13   07   09   06.2   11   059   117   1948   075   2001   012   1956   17   19.6   30   047   087   1941   180   1965   19   1963   00   04   01  
                                                                     
  *Leeming   07.2   +0.2   01.7   -0.6   12.6   10   -09.2   29   19   10   05   05.0   05   068   162   1945   077   1967   014   1972   11   07.4   01   033   055   1945   125   1978   16   1988   00   04   01  
  *Boulmer   07.7   +0.8   03.5   +1.1   12.5   10   -05.6   29   10   03   07   05.5   12   052   116   1945   077   1967   021   2002   14   10.8   02   052   087   1945   205   1978   17   1975   00   05   00  
  Eskdalemuir   05.6   +0.2   00.7   -0.1   09.7   10   -08.5   29   21   13   13   05.8   12   042   115   1911   074   1967   003   1912   11   11.0   09   075   047   1911   351   1993   33   1933   00   05   00  
  *Bishopton   06.6   -0.6   02.5   +0.3   10.9   10   -04.2   28   16   09   12   05.9   06   035   110   1921   072   2001   009   1956   11   20.0   30   071   067   1921   261   1999   15   1933   00   03   00  
                                                                     
  *Leuchars   06.8   +0.1   02.0   -0.1   12.0   10   -03.6   18   21   08   08   05.5   07   056   109   1921   082   1967   016   1934   11   19.4   03   063   099   1921   155   1978   08   1926   00   04   00  
  Dyce   07.2   +0.8   02.8   +1.3   13.5   11   -07.5   29   13   07   10   05.2   21   039   086   1941   067   1951   016   2002   07   15.6   03   089   111   1941   160   1978   20   1991   00   05   00  
  *Stornoway   08.4   +0.9   04.6   +1.3   12.1   11   -00.3   18   11   01   13   04.5   03   030   122   1880   057   1995   006   1884   06   13.8   22   075   060   1943   222   1985   29   1977   00   03   00  
  *Aldergrove   07.4   +0.3   03.5   +0.6   11.7   09   -02.1   25   13   07   13   06.0   06   034   098   1927   077   2001   017   1954   06   22.4   01   086   096   1927   195   1978   15   1963   00   02   00  
                                                                     
                                                                                                                                         
  Stations marked with an asterisk record sunshine electronically; comparisons      
  with earlier records are therefore somewhat speculative. Thorney Island's      
  sunshine figures are made at a nearby site.