A rare red warning for extreme heat has been issued for parts of the UK as temperatures are set to climb sharply over the next few days.
The warning covers the period from 09:00 on Wednesday to 21:00 on Thursday, and has been issued by the Met Office.
Temperatures could reach 38C or even 39C by Wednesday and Thursday. That would make this one of the most intense heat spells in recent years.
The Met Office says the heat is likely to affect health services, power supply, and transport networks. Delays and disruption are possible as systems come under pressure.
If highs do reach 35.6C or above, it would pass the current June record set in 1976. That would mark the hottest June day ever recorded in the UK.
Wider amber heat warnings are also in place across most of England and Wales until Thursday. These cover large parts of the country where temperatures will sit in the mid to high 30s.
Nights will stay warm too. That brings little relief after sunset, and sleep may be difficult for many people.
High humidity will add to the discomfort. The air will feel heavy, and conditions may become more stressful, especially in towns and cities.
Health officials are expected to remind people to stay hydrated, avoid peak sun hours, and check on those who may be more at risk during the heat.