Tuesday 11th August
It was such relief to find that Monday was a pleasant day without the recent intense heat, all due to the cooler air that flowed behind the cold weather front, which traversed the UK during the day. Eventually the thermometer peaked at 25.4C, logged at 15.31, being 3.8C above my long-term average. Unusually the temperature, after falling to a low of 12.3C at midnight began to edge upwards again reaching 15.2C for over an hour between 02.00 and 3.00. The back track of the cloud radar indicated that small banks of cloud temporarily drifted down from the north, before receding. It then began to fall again to plateau at 13.1C between 05.48 to 06.23 before beginning to rise again, in response to the sunrise at 05.46, to reach 17.3C by 08.00. The low was 0.5C above the average.
Sunshine greeted us again at the start to a new day on Tuesday. There has been a significant change in wind direction today, due to the high pressure easing eastwards towards Denmark today and eastern Europe extending over the next few days. This subtle shift in position will result in the breeze today and up to Thursday, coming in from an east-southeast or southeast direction. The airstream, having travelled over a very hot Continent, will waft very hot air across the UK heralding the start of a short lived, thankfully, fifth heatwave that could see maxima reach 34C on Wednesday and Thursday.
By Friday the forecast pressure charts indicate that an Azores high will begin to push across the country from the southwest. However, although it will be a significant anticyclone, the air will be rotating around it clockwise, as they do around high pressure systems, which will mean the wind will have a westerly or northwesterly component having travelled around its western and northern flank, across the mid-Atlantic, thus be much cooler.
The heat over recent months has been exacerbated due to the very dry ground. If we had received any precipitation in recent weeks, the rise in temperature for a day or two would have been muted slightly as evaporation of the moisture in th ground would have taken with it some of the stored warmth.
The longest UK heatwaves
Looking across the Met Office’s UK heatwave dataset from 1900 to 2026, the longest recorded UK heatwave spell listed (where at least one station in the UK met or exceeded its heatwave threshold) is from 18 July to 25 August 1995, lasting 39 days. The second longest is the recent 2026 spell from 30 June to 5 August, lasting 37 days, followed by 26-day spells in 1947 and 1990.
Other notable long-running events include 1916, with a 24-day heatwave, and several 23-day spells, including 1976, 1983, 2013 and 2018. These figures show that prolonged heat is not new to the UK, but recent years continue to feature prominently in the records.