The UK in May

 

Mike Hulme on last month’s weather

 

 

DAYTIME TEMPERATURES

Temperatures in May were well above the average for the time of year, most notably over the last 10 days of the month.  After a cool first week, the 12th May saw the warmest day of the year so far with an average nationwide daytime temperature above 20C.  The May warmth was quite uniform across the country, with a few locations – Bournemouth, Eskdalemuir, Aberdeen, for example – recording temperatures more than 2C above usual.  Aberdeen ended up as warm as Lowestoft, although normally in May the latter is nearly 2C warmer than Aberdeen.  The rather warm May means that UK temperature now during 2001 is slightly above the long-term average.

 

 

RAINFALL

May was the first dry month in the UK since the end of last summer.  Nationwide, rainfall totals were 38% below average and parts of the south coast and the western isles recorded less than 50% of average rainfall.  There was only one really wet spell in the month – 15-17th May, during which about half the monthly rainfall occurred.  The rest of the month was predominantly dry.  Only two locations – Lowestoft and Belfast - of the 20 monitored here ended up wetter than usual, and in each case only by a few mms.  The early May Bank Holiday was dry everywhere, very sunny, although rather cool.

 

 

SUNSHINE

With warm temperatures and a dry month, it was no surprise that sunshine totals during May were well above average - about 19% nationwide.  In relative terms, parts of Scotland benefited most and Aberdeen, Eskdalemuir and Kinloss each recorded more than 40% more sunshine that would be usual in May.  At the other extreme, Skegness disappointed in that totals were about 15% below normal.  The sunniest sequence of days was the 22-24th May, when each day recorded as a nationwide average over 12 hours sunshine.  The dullest day of the month was the 16th with only 1.8 hours of sunshine – it was also the wettest day.  The late May Bank Holiday was warm, although rather cloudy with a little rain in the north and west.

 

 

Dr Mike Hulme is a Director of the Tyndall Centre for Climate Change Research, at UEA

(more details at website at www.tyndall.ac.uk)

 

 

May 2001: Rather warm, sunny and dry

 

Daytime Temperature: 1.5C above average;          Rainfall:   38% below average;      Sunshine:  19% above average.

 

[all average figures are based on the 1951-80 average]

 

Mean monthly extremes:

 

Warmest          Ross-on-Wye                               18.1C

Sunniest          Folkestone                                      268 hours sun

Wettest          Belfast                                    64mm   

Coldest          Lerwick                                             11.0C

Cloudiest          Skegness                                        155 hours sun

Driest           Leuchars                                          17mm