Heatwave likely to be confirmed as record-breaking temperatures forecast

A significant story is unfolding on the international scene. Heatwave likely to be confirmed as record-breaking temperatures forecastImage source, Mike Kemp/In Pictures via Getty ImagesByMatt TaylorLead Weather PresenterPublished35 minutes agoA heatwave is expected to officially be declared for parts of the UK on Sunday as a spell of unusual May heat intensifies. 5C was recorded at Frittenden in Kent on Saturday - the highest of the year so far. The soaring temperatures could also lead to new national May temperature records being set on bank holiday Monday.

While the tourism and hospitality industry are welcoming the well-timed hot and sunny weather, the longevity of the heatwave is likely to have impacts on the health of some. Amber heat-health alerts remain in force for parts of the Midlands and eastern England until at least Wednesday. Image source, WeatherWatcherrs/Ani CaulWhen does hot weather become a heatwave?

The Details

This all depends on where you live and is based on the "normal" climate there. Met Office heatwave criteria sets the temperature for a heatwave at 25C in Scotland, Northern Ireland, much of Wales and northern England. For many other areas of England, as well as south-east Wales, it is 26 or 27C.

In London, most of the home counties and Cambridgeshire, it is 28C. These thresholds must be reached or exceeded on at least three consecutive days. It is possible that many areas will officially be classed as being in a heatwave when Sunday's temperatures are confirmed.

For some areas it is likely to turn into a prolonged heatwave. Image caption, Heatwave temperature thresholds must be reached for three consecutive days or moreSix ways to keep your home and yourself cool in hot weather Published3 days agoWhat's the difference between heat health alerts and extreme heat warnings? Published27 June 2025Temperature records may fallSaturday brought the UK its first 30C day of the year, and the earliest date 30C was reached since 1952.

What Experts Say

With heat set to build further across England and Wales on bank holiday Monday it looks increasingly likely that a new all-time UK May temperature record will be set. 8C is currently the highest temperature ever recorded in May. It was set on the Late Spring Bank Holiday Monday in 1944 at Tunbridge Wells, Horsham and Central London.

Current forecasts show the possibility of exceeding 33C in parts of south-east England. The night-time temperature record for May could also be swept aside too if any location stays above the 18. 9C set in Folkestone on the night of the 30-31 May 1947.

Image caption, Heat continues to intensify across many areas this bank holiday weekend. Forecasts show that some areas of England and Wales may stay above heatwave criteria for most of the week. 30C days in May the UK are relatively rare; however, it is conceivable we could see four or five recorded this week alone.

The development has drawn wide international attention, with diplomatic circles watching closely.