Weather Review of May 2011

Advertisment
  • Breezy but fine at Weston-Super-Mare on 01 May. Photo: Ben Birchall/PA Wire

    Faye Oughton, 20, enjoys the hot weather at the new Pink Mistress Tulip garden at Alnwick gardens close to Alnwick Castle, on 03 May. Photo: Owen Humphreys/PA Wire

    Visitors to Scarborough cover their faces as gale force winds, the worst in May since 1962, blow up a sand storm on the North Bay and promenade on 23 May. Photo: John Giles/PA Wire

    Emergency services tend to a car trapped by a fallen tree near Dunblane, as high winds brought chaos to some of Scotland's roads on 23 May. Photo: Andrew Milligan/PA Wire

    Sea water whipped up by high winds in North Queensferry during the gales of 23 May. Photo: Danny Lawson/PA Wire

    People relax in the changeable Bank Holiday weekend weather at the Hay Festival in Hay-on-Wye, Powys, on Saturday 28 May before rain came on Sunday and Monday. Photo: Ben Birchall/PA Wire

    An almost empty beach in Tynemouth on 30 May as the Bank Holiday ended disappointingly in many areas of the country. Photo: Owen Humphreys/PA Wire

  • Weather Review of May 2011
    31.05.2011 12:22


    The main features of the month were: 

    •     Three times normal rainfall in Western Highlands and Lake District

    •     Less than 25% normal rainfall in East Anglia

    •     Heathland/woodland fires in several areas during first week



    The first five days of May were dominated by a large blocking anticyclone in Arctic latitudes with strong easterly winds affecting the UK.  From the 6th-10th a deep depression lay to the west of Ireland with southerly winds across the country,  and from the 11th onwards lowest pressure was found to the west and north of Scotland with relentless southwesterly winds delivering copious amounts of rain to the western highlands, Cumbria, and parts of Northern Ireland.

    Mean maximum temperature for May ranged from 19.4°C at St James's Park and Heathrow (both London) to 10.8°C at Fair Isle (between Orkney and Shetland), while mean minimum temperature varied between 10.9°C at Olympic Park South (London) and 4.2°C at Braemar (Aberdeenshire). Mean maximum temperature ranged from close to the long-term average in western Scotland to 2.5degC above in East Anglia. Mean minimum temperature was 1.0 to 2.0 degC above the long-term normal in all regions. The Central England Temperature (CET) of 12.4°C was 1.1 degC above the long-term mean, the highest for May for just three years. In parts of Southeast England, East Anglia and the Midlands May had a lower mean temperature than April  – a rare event, but not without precedent.

    The highest maximum at a standard site (i.e excluding rooftop and mountain sites) in the UK was 25.4°C at Weybourne (Norfolk) on the 7th, while the lowest minimum was minus 6.3°C at Altnaharra (Sutherland) early on the 4th. The lowest daytime maximum was 8.2°C at Dalwhinnie (Inverness-shire) on the 24th, and the warmest night was that of the 7th/8th with a minimum of 16.3°C at Weybourne (Norfolk).

    Rainfall averaged over England and Wales (including a small estimated figure for the 31st) during May was 49mm which is 80 per cent of the average for the standard reference period 1971-2000, higher than May 2010 but not as high as May 2009;  in the last 100 years 31 Mays were drier while 69 were wetter. The equivalent figures for Scotland were 112mm and 184 per cent of the normal amount, and for Northern Ireland 67mm and 120 per cent. Monthly totals at routinely-available sites ranged from 445mm at Cluanie Inn (Wester Ross) to just 4mm at Manston (Kent). Substantial parts of East Anglia together with east Kent received less than 10mm rain during the month.

    Sunshine averaged over England and Wales (including an estimated figure for the 31st) during May was 212 hours which is 105 per cent of the 1971-2000 mean, the lowest since 2008; in the last 100 years 45 Mays were sunnier while 55 were duller.  The equivalent figures for Scotland were 191 hours and 109 per cent, and for Northern Ireland 197 hours and 97 per cent.  Largest total in the UK was 270 hours at Manston (Kent) and the smallest was 115 hours at Eskdalemuir (Dumfriesshire).

    The gale in Scotland, Northern Ireland and northern England on the 23rd was probably the worst in May since 1962 (16 May), with gusts at low-level sites of 70 knots at Inverbervie (Kincardineshire) and 67 knots at Drumalbin (Lanarkshire).

    The Central England Temperature for the spring quarter (March, April, May), was 10.4°C, the highest in the entire 352-year long record, beating by 0.2degC the previous record in 1893. England and Wales rainfall for the three-month period of 88mm was the lowest since 1990.

     

    Regional Breakdown 

    Difference from the average (1971-2000)

    Mean Max

    (deg C)

    Mean Min

    (deg C)

    Rainfall

    (per cent)

    Sunshine

    (per cent)

     

     

     

     

     

    Scotland (Highlands and Islands)

    +0.5

    +1.0

    174

    110

     

     

     

     

     

    Scotland - Central Belt and east coast

    +0.8

    +1.2

    215

    109

     

     

     

     

     

    Northeast England

    +1.8

    +1.3

    95

    117

     

     

     

     

     

    East Anglia

    +2,4

    +1.3

    42

    127

     

     

     

     

     

    Midlands

    +2.2

    +1.3

    67

    101

     

     

     

     

     

    Southeast England

    +2.2

    +1.2

    48

    123

     

     

     

     

     

    Northwest England and North Wales

    +0.7

    +1.9

    182

    83

     

     

     

     

     

    Southwest England and South Wales

    +1.4

    +1.3

    80

    94

     

     

     

     

     

    Northern Ireland

    +0.7

    +1.7

    128

    98

     

     

     

     

     

    IrishRepublic

    +0.4

    +1.7

    155

    88

     

     

     

     

     

     

    © Philip Eden 110531