A small, but deep slow-moving depression was centred over the UK at the beginning of August and brought changeable weather for the first week or so. Some rain was recorded on seven of the first nine days, ranging from 8.4mm on 1st to 0.4mm on 9th. The daytime temperature ranged from 19.°C-23.8°C and nights fell to the low teens. The wind was light to moderate from all quarters.
The barometer began to rise rapidly from 7th and continued to rise until the end of the month (with one interruption from 18th – 22nd).
From 10th – 20th there was still much cloud cover with some sunny spells and a mainly light south-westerly wind. Temperatures were slightly higher, up to 24.1°C on 14th, the maximum for the month. There was no rain.
On the night of 21st/22nd 9.5mm of rain fell, enough to recharge water butts to the relief of us gardeners. It was, however, the last for the month and brought the total for August to 32.9mm, 58.6% of average. This was less than a third of that in 2020 and made it the driest August since 2013. The three summer months (June, July & August) added up to 155.8mm, 101.4% of average. For the year so far, the total is 458.4mm or 108.8% of average.
The last 10 days continued dry but mainly cloudy, with a chilly north easterly wind. The temperature dropped to 10.4°C on the night of 29th, the lowest of the month. The warmest night was 16.8°C on 21st. It was the coolest August since 2017, just 0.27℃ above long-term average.
Overall, August 2021 was a disappointingly gloomy, chilly but dry month, certainly not like summer at all.
25 year Rainfall averages are from 1992-2016
30 year Temperature averages are from 1981-2010
30 year temperature averages for Steventon are from 1981-2010
Oxford rainfall averages are from 1992-2011
Summary data from Mike Wilkins, January 2014.