The current heat wave is not expected to break any daily temperature records, but the Met Office announced on Thursday that there were eight days in 2026 when heat reached or exceeded 34C.
There were two during the May heat wave, four in June and two so far this year, which is a record for a calendar year, surpassing 1976 and 2020. Temperatures are expected to rise again to +34°C on Friday.
During the June heatwave, temperatures peaked at 37.7C in Lingwood, Norfolk, beating the previous June record of 35.6C.
Wales also recorded its hottest June day with a temperature of 35.9C in Cardiff, while Northern Ireland matched its June record with 30.8C in Castlederg, County Tyrone.
Scotland fell just short of its all-time June record of 32.2C, set in 1893. In June the maximum temperature was 31.2°C in Threave and Dumfries and Galloway.
In this July heat wave, the highest temperature so far was 35.5C at Wisley in Surrey on Thursday.
Although temperatures will cool slightly by the weekend, many places will still reach official heatwave thresholds for much of next week.
People may make comparisons to 1976, when the UK had 16 consecutive days of temperatures above 30C, but that record is unlikely to be broken.
The highest temperature recorded in the UK was during the 2022 unprecedented heatwave, when a staggering 40.3C was recorded in Coningsby, Lincolnshire.