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graphs      CLIMATE-UK.COM'S  REVIEW  OF  THE  BRITISH  METEOROLOGICAL  SCENE
     MONTHLY  SUMMARY
     No. 581 For    MAY    2004
                 CYCLONIC FIRST WEEK, THEN MOSTLY ANTICYCLONIC
Text Box: Pressure was low over the British Isles during the first ten days of May, but high pressure dominated the scene for most of the rest of the month, although Atlantic fronts moved in during the last few days. A slackening north-easterly flow on the 1st maintained cool, grey weather across southern Britain but it was sunny from the north Midlands northwards, and the 2nd was a fair and pleasantly warm day over much of the UK. A cold front moved south-eastward across the country the following night and stalled across East Anglia and the Southeast on the 3rd (the May Day bank holiday) where it was a cool and wet day. A vigorous Atlantic depression approached Scotland later that day, deepening on the 4th to 971 mbar over central Scotland - probably the lowest May pressure in the UK since 1943 - and further heavy rain crossed the country. The next two days brought widespread showers with hail and thunder as the depression slowly filled up in situ. A belt of rain crossed England from the east on the 8th and the north-easterly wind kept it very cool along North Sea coasts, but Shetland became warm and sunny (Baltasound 20.3ēC on the 9th) thanks to a dry north-easterly off Norway. That warm air spread to most of the UK over the next few days under a sluggish northerly flow, the temperature reaching 23.7ēC at Glentress (Peebles) on the 10th, but thunderstorms broke out widely from the Scottish
Text Box: Highlands to the English Channel. It turned cooler temporarily during the next few days, but from the 14th to the 19th most parts of the country were fine and warm with long sunny periods, the temperature widely reaching the low 20s, and touching 25ēC in London on the 17th and 19th. A southward moving cold front brought showers and a sharp drop in temperature on the 19th/20th, but much of the UK became sunny again during the following week although there was widespread ground frost at night; at Kinbrace, Sutherland, the air minimum on the 27th was -3.7ēC. There were a few well-scattered showers on the 25th/26th, but an eastward-moving occlusion brought the first measurable rain for 22 days to parts of west Wales, Cornwall and Devon on the 28th. The next few days were rather cloudy and showery, and on the 31st (the late spring bank holiday) a belt of rain advanced slowly across the West Country and Wales, but most other regions stayed fair until late. Mean maximum temperatures were 1-2degC above the 30-year average, while mean minima were 0.5-1.5 degC above, and it was generally the warmest May for three years. Rainfall was slightly above average in parts of East Anglia and the Southeast, but below in all other regions, and Leeming, North Yorks, recorded only 15mm. Sunshine totals were below normal in northern Scotland and locally in East Anglia and the Midlands, but well above average elsewhere; a few sites in Cornwall and Devon had their sunniest May since 1989 with aggregates of over 300 hours locally.
                                                                                                                                         
                       TEMPERATURE                                SUNSHINE                             RAINFALL                                                       
                                                                                                                                 
                                                                                                                                 
                   
No. of days with grass minimum below 0ēC
                      Highest and lowest totals    
Maximum fall in 24 hrs (beginning 09 h)
                Highest and lowest totals    
Days with snow or sleet
 
Days with fog (Vis <220 yards at 09 h)
 
     
Difference from average
   
Difference from average
             
Days of no sunshine
                      on record for month                         on record for month        
                                                                                         
           
Highest maximum
   
Lowest minimum
         
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