Temperatures in parts of the UK are set to climb beyond 30C with officials urging people to take care in the heat.
The Met Office issued a heat-wave alert covering southern England and the Midlands with Friday expected to top Thursday’s hottest temperatures of the year so far.
Public Health England said elderly people and those with long-term illnesses should take particular care.
There was also a warning of thunderstorms and heavy showers.
A high of 32C has been forecast for Friday, with the Met Office predicting rain in Scotland and Northern Ireland but very warm, humid conditions elsewhere.
BBC weather forecaster Nick Miller said Thursday’s “hot spots” would be “even hotter” on Friday after a night of thunderstorms in some areas, with more torrential rain forecast on Friday night into Saturday.
The Met Office declared a level two heat-wave alert. This warning is triggered by at least a 60% chance of temperatures being high enough on at least two consecutive days to have a “significant effect on health”.
It also issued a yellow weather warning for thunderstorms across the South West and Wales, including torrential rain, hail and disruption.
From Friday night into Saturday the warning extends across England, Scotland and Wales.
Public Health England renewed its advice to people to take care in the heat, reports the BBC.
Dr Paul Cosford, director for health protection, said: “While many people enjoy hot weather, high temperatures can be dangerous, especially for people who may be particularly vulnerable such as older people, young children and those with serious illnesses.”
People should stay out of the heat during the hottest time of the day and have plenty of cool drinks, he said.
