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graphs      CLIMATE-UK.COM'S  REVIEW  OF  THE  BRITISH  METEOROLOGICAL  SCENE
     MONTHLY  SUMMARY
     No. 615         For    MARCH    2007
                 EXCEPTIONALLY SUNNY.  VERY WET AT FIRST THEN LARGELY DRY
Text Box: were reported on the 18th. All parts of the country had frequent showers of snow, sleet and hail during these three days, and snow lay 9cm deep at Aviemore on the morning of the 20th. As the strong winds abated, the overnight temperature fell to -8.2°C at Loch Glascarnoch (Wester Ross) on the 20th/21st, and to -5.6°C as far south as Benson (Oxon) the following night. Braemar (Aberdeenshire) logged a maximum of -0.1°C on the 20th - the only incidence of a sub-zero day anywhere in the UK during March. A frontal trough advancing from the northwest cut off the Arctic airflow on the 21st and 22nd, but not before snow had fallen for a couple of hours over East Anglia and the Southeast on the morning of the 22nd, though snow-cover was transitory even over the hills. Rapidly rising pressure led to the establishment of a large anticyclone over Scandinavia until the 28th, delivering an easterly airflow to the UK. A depression affected the country on the 29th and 30th, but a strong northeasterly airflow returned at the end of the month. The 24th was cold, windy, dull and drizzly over most of England, with widespread hill fog, but from the 25th to the 28th it was warm and sunny by day - up to 18.6°C at Herstmonceux (Sussex) on the 27th - but with frost and fog at night. This episode was also notable for a persistent thick atmospheric haze. The next two days were colder and cloudier with rain in many places, notably in central and eastern Scotland, but much of the UK was sunny again on the 31st. Mean monthly temperatures were between 1 and 2 degC above the long-term mean except in Northern Ireland (where they were close to normal), the excess being markedly greater by day than by night in southern and eastern regions. In spite of the very wet start, only northern and western Scotland ended up with a wetter-than-average March and locally in the northwest highlands there was twice the normal amount of rain; by contrast many places in east and northeast England had less than 25mm of rain during the entire month. Sunshine aggregates were above the long-term average in all regions, but especially in southern England where Weymouth’s total was 219 hours. During the last 100 years only the Marches of 1907, 1929, 1933 and 2003 were significantly sunnier.
Text Box: After a very disturbed first week there was a strong rise of pressure over southern Britain during the second week although Scotland remained under the influence of a westerly flow. A short-lived northerly outbreak between the 18th and 21st was followed by mainly easterly winds during the last week or so. The mean monthly pressure pattern showed a markedly diffluent westerly flow covering the UK; anomalies ranged from zero in Shetland to +4mbar at Valentia. A vigorous southwesterly type prevailed until the 8th with active depressions and troughs crossing the country at frequent intervals. All parts of the UK had frequent rain, heavy at times especially in the north and west, but between the rain belts there was a good deal of sunshine, and all regions remained consistently mild. The weather was particularly bad on the 5th and 6th: a gust of 65kn was recorded at Barra (Western Isles) on the 5th, and one of 63kn at Langdon Bay (Kent) on the 6th. Keswick (Cumbria) recorded 54mm of rain on the 5th alone, while Capel Curig (Snowdonia) collected 81mm over the two days. Between the 8th and 17th a strong southwest to westerly type persisted over northern Britain, but pressure was now much higher over southern districts and a series of high pressure cells travelled from west to east along the English Channel or across northern France. It became sunny and rather warm in southern, central and eastern England, and the warmth extended to eastern Scotland at times too, notably on the 10th when 15.7°C was recorded at Fyvie (Aberdeenshire). Further south, the warmest days were the 11th and 12th when the temperature widely exceeded 15°C, peaking at 18.5°C on the 12th at East Malling (Kent). By contrast, northern and western Scotland was cloudy and windy, and upwards of 200mm fell during the ten-day period in the northwest highlands. Gusts over 70kn were recorded at Foula (Shetland) and Benbecula (Western Isles) on the 16th and 17th. On the 18th a deep depression tracked past northern Scotland and a vigorous cold front introduced a much colder northwesterly airflow which veered northerly on the 19th and 20th. Peak gusts of 94mph at Foula and 91mph at Sule Skerry and Fair Isle