The summer so far has been around 1°C warmer than average for the UK, which would potentially place it within the top ten warmest summers on record, but it’s still too early to make a confident statement about final rankings. This may come as a surprise to some, especially for those in the southeast and London, who have had a much wetter and duller summer than average, with many areas seeing more than 50% more rainfall than their long-term averages.
With a few days still to go until the full figures are published for summer 2021 at the start of September, high temperatures in Scotland and Northern Ireland have helped pull the UK to within the top 10 for warmest summers according to mean temperature, with still some room for manoeuvre before the season is out. The UK has a mean temperature for summer around a degree higher than the average, currently sat at 15.4°C, with still some time to change.
In fact, Northern Ireland has so far seen one of its warmer summers using the same measurement (15.0°C), and Scotland (13.8°C) has also been notably warm. Western areas, and especially western Scotland, have also seen much less rainfall than the averages, with Scotland, so far, seeing just 62% (188.1mm) of its average rainfall for the season, and Wales 66% (189.5mm).
With the best of the dry and warm conditions to be found in northern and western areas of the UK, it has been a markedly different story for the southeast and some southern areas this summer so far.
Greater London has so far seen an average of 220.2mm of rain, which is 48% more than their long-term average for summer, although not enough to trouble the all-time records for the area. They’re joined by Hampshire (245.2mm, 49% more than average), Surrey (240.3mm, 54% more than average) and West Sussex (250.9mm, 52% more than average) in seeing significantly more rain than their usual summer conditions.
As you might expect, these areas have also seen less of the sun than average, although there is still time in the season for this to shift more with some good spells of sunshine expected before the end of the month.
Of course, this summer did see a heatwave in July, which saw the Met Office issue its first ever amber extreme heat warning, as Northern Ireland broke its all-time temperature record on 21 July with 31.3°C recorded at Castlederg. This extended spell of warm weather in July, with stubbornly high night-time temperatures, has helped to lift the averages for the season, with the highest temperatures in that period also seen over western areas, although the rest of the UK was widely warm.
However, perceptions that summer has been below average for some could come from the fact that August hasn’t yet served up particularly high individual maximum temperatures. So far, the highest temperature recorded this month was at Tyndrum, Scotland with 27.2°C. Only two times in the last ten years has 30°C not been reached in August in the UK and on every occasion in the last 20 years the highest temperature for August was reported in England.
Temperatures have, however, been fairly consistent over the month of August. So, although there hasn’t been any creeping up past 30°C just yet, the average maximum temperature is actually near to the long-term average at the moment, at 19.1°C. August has also been slightly drier than average so far for most, although some regions are close to or above average such as Northern Ireland, eastern Scotland and parts of southeast England.
Dr Mark McCarthy of the National Climate Information Centre said, “Obviously there’s still time before the month and season is over, but summer so far is certainly looking drier and warmer than average, that’s despite some of the wet, dull conditions we’ve seen in the southeast in particular.
“Some of the flooding seen in London in July has seen some individual stations report almost twice their normal summer rainfall but the north and west of the country has experienced plenty of sunshine through June and July, although most of the country has been duller than average through August.”
Get the latest forecast for the rest of the month on the Met Office website.
Note: Statistics in this blog are representative of the period to 25 August 2021. The full statistics will be released at the end of the month. Summer, as defined in these statistics, runs from the 1 June.