Rare amber health alert issued for large parts of UK as Met Office warns of 33C scorcher

A rare amber alert has been issued for heat in large parts of England. A yellow alert is in place for the rest of the UK. The alerts, issued by the UK Health Security Agency (UKHSA), are due to be in place for 33 hours from 9am on Tuesday (August 11), until Wednesday at 6pm.

The amber alert - described as an "enhanced hot weather response" - covers East Midlands, West Midlands, East of England, London and the South East. This marks the fourth heatwave of the summer, with temperatures expected to peak in the mid-30s in the coming days, the Met Office said. Temperatures are likely to rise the most in central and southern England, peaking at around 33C in London on Tuesday. Yet forecasters added that there is also a risk of isolated thunderstorms and infrequent outbreaks of rain alongside the high heat.

A yellow alert, also in place from 9am on Tuesday until 6pm on Wednesday, covers the North East, North West, Yorkshire, The Humber and the South West.

Greg Dewhurst, a senior meteorologist at the Met Office, said the temperatures over coming days mean that some parts of the country will meet heatwave criteria - three consecutive days exceeding a certain threshold - as early as Tuesday. This threshold varies from 25C to 28C depending on location.

He said: "Temperatures are going to rise over the coming days, particularly across England and Wales, but it is not going to be felt quite as much across parts of Northern Ireland and Scotland - it's not going to be widespread heat everywhere.

"And the reason for that is we've got high pressure to the south east of the UK at the moment and low pressure to the north west and west.

"But through Monday, we start importing some of that hot and humid air, and we're looking at highs of around 31C across central and southern England, with the rest of England and Wales getting towards the high 20s, and Northern Ireland and parts of Scotland in the low 20s.

"The heat may spark one or two heavy showers and thunderstorms across south-west England and Wales, but they'll be very isolated.

"And then Tuesday looks largely dry, with plenty of sunny spells - it could well be the peak of the heat.

"Temperatures are set to rise to about 33C across central and southern England, but again, this could spark off a thunderstorm by the afternoon and evening time.

"And some places will hit heatwave thresholds on Tuesday, while some places will hit it on Wednesday - it depends on the area."

Forecasters at the Met Office said that, in addition to high daytime heat, warm nights are also likely in south-eastern parts of the UK.

They add that there is a chance of a tropical night in a few places, where temperatures do not drop below 20C overnight.

Into Wednesday (August 13), however, the high pressure will "edge away", according to Mr Dewhurst. From here, temperatures will be lower, with a bit more cloud, but there still could be highs in the low 30s. On Thursday, temperatures are set to peak around 29C, again with more cloud and a few showers, before a drier Friday with sunny spells ahead of the weekend.