back
graphs CLIMATE-UK.COM'S REVIEW OF THE BRITISH METEOROLOGICAL SCENE
MONTHLY SUMMARY
No. 679 For JULY 2012
VERY DULL, VERY WET, AND RATHER COOL UNTIL THE 20TH, THEN A WARM SUNNY WEEK OVER ENGLAND AND WALES
Text Box: July was cyclonic or westerly until the 20th, but an anticyclonic spell followed over England and Wales, though the last few days of the month were again cyclonic. Thanks to the anticyclonic intervention, mean pressure distribution for the month was much less abnormal than it had been during June; the main anomaly centres were  -5 mbar over the UK and +5 mbar over southeastern Greenland.

Pressure was low to the north of Scotland on the 1st, and a further large depression moved slowly towards Ireland over the next few days, thence heading southeastwards into northern France. A new depression heading west from Benelux became slow-moving over the UK between the 6th and 9th before drifting northeastwards into Scandinavia. Yet another depression crossed Wales then England on the 13th/14th. The first three days of July were cool and cloudy with showers or longer outbreaks of rain in most places, but the 4th and 5th were rather warmer though no less unsettled, and 53mm rain fell in a thunderstorm at Howden (East Riding) on the afternoon of the 5th with 20-40mm in other parts of northern England. Heaviest rain moved to southern England on the 6th and 7th, triggering flooding in Devon and Dorset; 88mm fell at Weymouth and 77mm at Portland (both Dorset) during the 48h period. The weather remained cool and unsettled with further heavy rain at times for several more days, and a northeasterly flow developed over Scotland, delivering unseasonably low temperatures to some areas, and on the 7th the day's high at Aviemore (Inverness-shire) was just 10.3C. Heavy rain hit mid-Wales, Shropshire and the Suffolk coast on the 13th, with 45mm at Southwold (Suffolk) and 42mm at Pennerley (Salop).

A changeable westerly flow, though with pressure relatively high at times near southern England, dominated between the 15th and 20th, then pressure rose further over southern districts between the 21st and 24th though a disturbed southwesterly type continued over central and northern Britain.  Pressure was flat over the UK for a couple of days before a northwesterly type took over from the 27th onwards.
Text Box: During the third week of July rain fell less frequently in southern, central and eastern England, whereas the heaviest falls tended to occur more frequently in upland areas of northern and western Britain. Most parts of the country remained cool and cloudy, however, and by the 20th sunshine aggregates had only reached 20h at Eskdalemuir (Dumfriesshire) and 23h in both the Edinburgh and Aberdeen areas. It became dry with sunny spells over much of the country on the 21st, but rain returned to parts of Scotland, Northern Ireland and northern England over the next few days and 62mm fell at Eskdalemuir in 48h on the 22nd/23rd; meanwhile southern and central parts of England and Wales became sunny and very warm between the 23rd and 26th with highs typically between 27 and 30C; highest of all was 30.7C at St James's Park (London) on the 25th. The highest minimum during this period was 19.1C at Llanfairfechan (Caernarfon) overnight 23rd/24th. The warmth was confined to southern England on the 27th, and showers broke out in northern and western districts and also the extreme south-east. The remainder of the month was rather cool, and there were widespread heavy showers on the 29th, many accompanied by thunder and hail. The 31st was fine and cool in Scotland with the month's lowest minimum of 0.8C at Tulloch Bridge (Lochaber), but rain fell widely over England, Wales and Northern Ireland.

Over England and Wales, July 2012 was no cooler than that of 2011, but five of the last six Julys have fallen short of the 1981-2010 average. Mean maxima were typically 1.0 to 2.5 degC below the long-term average, whereas mean minima were 0.0-1.0 degC below. Over England and Wales there were only ten wetter Julys in the last 100 years though two of those occurred recently - in 2007 and 2009. Rainfall totals ranged from 209mm at Spadeadam (Cumbria) to 35mm at Kirkwall (Orkney). Sunshine aggregates ranged from less than 10 per cent below normal locally in eastern England to 60 per cent below at Eskdalemuir and Aberdeen. Totals ranged from 210h at Jersey airport to 60h at Eskdalemuir and 69h at Dyce (Aberdeenshire).
                                                                                                                                               
    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   20.5   -0.5   12.3   -0.2   29.8   25   08.4   30   00   00   01   12.0   23   143   076   1910   321   1911   109   1913   06   22.0   07     107   195   1910   193   1924   05   1921   01   00   00  
  *Thorney Island   19.5   -2.3   12.7   -0.2   27.1   25   08.7   30   00   00   00   13.5   23   187   082   1958   336   2006   153   1978   10   18.2   06     106   213   1941   122   1945   06   1949   00   00   00  
  *Wattisham   20.3   -0.3   11.5   +0.2   27.7   25   06.4   30   00   00   03   15.2   23   155   080   1968   295   1976   131   1978   08   24.4   13     * 111   224   1960   101   1987   05   1977   01   00   00  
  *Wittering   19.9   -0.2   11.6   0.0   27.5   24   06.9   12   00   00   03   14.7   23   163   085   1955   283   2006   115   1965   20   09.6   04     045   087   1955   153   2004   06   1977   02   00   00  
                                                                       
  *Lyneham   19.4   -1.1   11.5   -0.2   27.9   25   08.4   12   00   00   07   15.0   23   159   073   1952   314   2006   129   1965   09   18.0   12     100   202   1945   149   2007   04   1955   01   00   00  
  Ross-on-Wye   20.7   0.0   12.0   0.0   27.7   24   06.9   12   00   00   00   12.1   24   170   090   1915   311   2006   095   1944   11   20.4   06     096   188   1859   197   1872   06   1935   01   00   00  
  *St Athan   18.4   -1.3   12.4   +0.2   26.7   26   08.8   12   00   00   03   14.7   23   181   083   1954   319   1955   131   1965   11   31.4   06     135   195   1954   188   2009   13   1977   00   00   00  
  Culdrose   17.7   -0.7   12.4   -0.1   24.8   25   07.1   21   00   00   07   14.2   22   188   083   1961   306   1971   117   1991   09   32.6   06     098   171   1961   197   2009   05   1999   00   00   00  
                                                                       
  *Edgbaston   19.6   -1.3   12.1   -0.5   28.0   24   08.5   12   00   00   00   13.4   23   176   096   1887   285   1990   067   1888   11   16.8   06     072   159   1887   183   2007   07   1911   02   00   00  
  *Valley   16.7   -1.7   12.3   +0.1   20.2   07   07.2   21   00   00   06   14.2   07   * 112   055   1946   341   1955   115   1986   09   16.4   06     071   130   1941   127   2010   09   1983   00   00   00  
  *Woodford   18.6   -0.8   11.3   +0.3   25.7   24   06.1   21   00   00   01   10.0   22   143   084   1945   280   2006   082   2010   11   20.6   28     168   228   1942   187   1973   10   1999   01   00   00  
  *Watnall   19.4   -0.7   11.9   +0.3   27.8   24   07.6   12   00   00   05   14.9   24   144   076   1948   273   2006   087   1965   11   17.6   06     128   249   1942   148   1973   11   1982   01   00   00  
                                                                       
  *Leeming   18.7   -1.2   11.4   +0.1   24.6   24   05.6   21   00   00   05   10.1   15   110   065   1945   276   2006   091   1965   11   14.6   11     071   144   1947   139   2009   09   1984   01   00   00  
  *Boulmer   17.0   -0.8   11.0   -0.5   23.9   23   07.4   31   00   00   02   11.5   31   129   071   1945   268   1955   105   1957   12   23.4   10     106   191   1945   155   2009   07   2006   00   00   00  
  *Eskdalemuir   16.1   -1.5   09.2   +0.3   21.2   25   01.7   31   01   00   07   10.2   31   * 060   039   1911   266   1989   069   2010   02   33.6   22     203   199   1911   269   1988   25   1913   00   00   00  
  *Bishopton   17.9   -1.0   10.7   +0.2   22.6   05   05.5   31   00   00   06   15.6   25   109   062   1921   297   1989   086   1931   07   26.0   17     * 164   248   1921   155   2010   11   1984   00   00   00  
                                                                       
  *Leuchars   16.9   -1.6   10.3   -0.2   20.8   22   06.8   15   00   00   07   14.0   25   102   053   1922   262   1955   091   1931   07   25.8   18     124   200   1922   181   1940   13   1983   00   00   00  
  *Dyce   16.3   -1.5   10.4   +0.6   21.9   24   05.1   21   00   00   08   10.8   31   * 069   041   1941   263   1955   078   1968   07   24.2   07     097   137   1941   198   1957   13   2003   00   00   00  
  *Stornoway   15.2   -0.4   09.9   -0.2   20.8   03   06.6   14   00   00   02   11.7   02   096   068   1880   227   1917   057   1939   10   11.4   22     056   082   1943   165   1988   14   1955   00   00   00  
  *Aldergrove   17.6   -0.7   10.7   -0.2   20.8   05   06.4   21   00   00   05   13.7   26   104   071   1927   274   1955   080   2010   07   10.8   23     076   085   1927   155   1950   12   2000   00   00   00  
                                                                       
                                                                                                                                               
  Stations marked with an asterisk record sunshine electronically; comparisons      
  with earlier records are therefore somewhat speculative.   * New low record   * New high record  
  Averages are for 1981-2010.