The UK in September

 

Mike Hulme on last month’s weather

 

 

DAYTIME TEMPERATURES

September was a cool month, daytime temperatures during the middle of the month dipping to more than 3C below the seasonal norm.  The only region to exceed average temperatures was the south of England and even here only by a few tenths of a degree.  Elsewhere, Birmingham and Scarborough recorded average monthly daytime temperatures nearly 2C below usual.  The warmest days were the 1st of the month and the 28th, the latter coinciding with a deep southerly airflow that also brought rain with it.  Following a reasonably warm late spring and summer, the year 2001 in the UK is still averaging just above the long-term average.  Worldwide temperatures continue to be well above the 1961-90 average and 2001 will continue the long sequence of globally warm years.

 

 

RAINFALL

Rainfall was patchy during September, although a wet final week saw the nationwide total for the month reach 89% of the long-term average.  The eastern coastal regions, especially East Anglia, were the wettest in relative terms, Lowestoft recording over 120mm of rain, more than double its September average.  Folkestone, Skegness, Scarborough and Aberdeen were also wetter than usual for this time of year.  The south of England, Wales and northern Scotland were generally dry, rainfall in the southern counties failing to reach 50% of average.  There were no really dry spells during September and, curiously, the wettest days in the month all occurred on either Tuesdays or Wednesdays.  The very wet late winter/early spring period means the year as a whole remains wet.

 

 

SUNSHINE

Although September overall was rather dry, it was also a cloudy month with sunshine totals on the low side.  The southern counties recorded the best of the sunshine, but Tiree in the Western Isles also was sunny and recorded 38% more sunshine than is usual for September.  The best of the sunshine occurred during the first half of the month, the sunniest day being the 8th.  Not surprisingly, with much of the rain falling around the eastern coasts, places like Lowestoft and Scarborough recorded the lowest sunshine totals.

 

 

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

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

 

 

September 2001: Cool; wet in the east

 

Daytime Temperature: 0.5C below average;          Rainfall:   11% below average;      Sunshine:  10% below average.

 

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

 

Mean monthly extremes:

 

Warmest          Bournemouth                                  19.1C

Sunniest          Guernsey                                        196 hours sun

Wettest          Morecambe                           167mm 

Coldest          Lerwick                                             11.9C

Cloudiest          Kinloss                                   67 hours sun

Driest           Guernsey                                        16mm