Yellow heat warnings are due to be in place for most of England this week as daytime temperatures are expected to reach 30C (86F).
The warning from the UK Health Security Agency (UKHSA) came into effect at 8am BST on Monday and will remain in place in eight regions until Thursday afternoon.
A yellow warning indicates weather conditions may pose a risk to people, especially those who are vulnerable.
The UKHSA said there may be minor impacts across the health and social care sector.
What's the latest weather forecast?
The next few days are expected to be the hottest so far this summer as warm air moves northwards across the UK.
Scotland and Northern Ireland are expected to be the warmest on Monday with maximum temperatures between 24 and 26C, before cooling off from the west on Tuesday under partly cloudy skies.
However, the heat is expected to linger in England and Wales, with temperatures reaching 28-29C in the south-east by mid-week and continued sunshine.
Some areas could reach the Met Office's official heatwave threshold, and nights will be warmer and more humid than we're used to these days.
The weather is expected to become cooler and wetter by the end of the week, but there is a lot of uncertainty about how quickly that change will occur.
If you have plans further down the line, such as for Glastonbury, we recommend keeping an eye on the BBC Weather forecast over the next few days for the latest updates.
Where can I find the latest heat stroke warnings?
A yellow alert has been issued for all regions except the Northeast. [UKHSA]
A yellow heat health warning will be in place for eight areas of England from 8am on Monday 24 June.
East Midlands
West Midlands
Northwest
Southeast
Southwest
East of England
London
Yorkshire and the Humber
The Northeast is unaffected.
The warning will remain in effect until 5pm on Thursday 27th June.
The weather is expected to become colder, cloudier and wetter by the end of the week, but the Met Office said it was uncertain how quickly that change would happen.
What is a heat stroke warning?
The Weather Health Warning System, run by UKHSA and the Met Office, was introduced in June 2023.
The service is available in England only. The BBC has contacted Public Health Wales for comment.
Weather alerts are only available to those who register and will be sent via email.
Heat health warnings are typically issued between June 1st and September 30th, and cold health warnings are issued between November 1st and March 30th.
The system will alert the public and send direct instructions to NHS England, the Government and other medical professionals during periods of severe weather.
Alerts are categorized according to severity and include the following:
Major weather conditions expected over the next few days
Learn more about how weather conditions affect each region
Links to additional information, advice and guidance
The system was designed to reduce illness and death during extreme weather events by improving communication between the public and relevant agencies.
[BBC]
