Britain is bracing for its third heatwave of the year, with temperatures expected to climb above 30C starting this Friday. The Met Office predicts highs between 28C and 31C from Friday through Monday, following a period of more average temperatures.

While heatwave conditions are anticipated, forecasters indicated that this upcoming event is unlikely to reach the extreme temperatures or humidity levels experienced in recent weeks. A heatwave is officially defined by the Met Office as three consecutive days where daily maximum temperatures meet or exceed a specific threshold, which varies by region.

For London and surrounding counties, the threshold is 28C. With temperatures forecast to reach at least 28C for four consecutive days from Friday to Monday, the UK is expected to officially re-enter heatwave conditions by Sunday.

Earlier in the week, the UK experienced showers and rain in some areas, with thunderstorm warnings issued for Northern Ireland and parts of Scotland. The south and southeast of England, however, were expected to remain drier and warm.

The build-up of high pressure from the Azores is contributing to the anticipated warmer conditions, particularly across England and Wales. "Although a return to heatwave conditions is looking increasingly likely for some areas, the likelihood of such extreme high temperatures or high levels of humidity as last week is currently low," stated Met Office deputy chief forecaster Tony Wisson.

This comes after a provisional June temperature record of nearly 38C was set on June 26, 2026, with a high of 37.7C recorded in Lingwood, Norfolk. This surpassed the previous June record of 35.6C from 1976. The country also recorded two of its top ten hottest days on record during the recent heatwave, including 37.7C in Lingwood and 36.7C in Merryfield, Somerset.

The extreme heat in late June led to significant disruptions, including school closures, record ambulance callouts, train cancellations, and hospital critical incidents. Water-related incidents during the heatwave resulted in at least 11 deaths, including that of a 15-year-old boy.

Earlier in May 2026, the UK recorded its hottest ever day in May, with highs of 35.1C in England and 32.9C in Wales. That heatwave also saw at least 17 deaths related to water incidents. In 2025, the UK experienced four heatwaves, with the highest temperature recorded being 35.8C in Faversham, Kent, on July 1.