The UK Health Security Agency (UKHSA) has announced the first ever national emergency heat red alert for Monday and Tuesday.
The level 4 heat alert is due to a forecast of a record high temperature of 40°C (104°F) for south-east England.
"Illness and death may occur among the fit and healthy, and not just in high-risk groups".
- UK Health Security Agency
Health officials fear people living alone on upper floors of buildings are among those who could perish, as people did in Paris in 2003.
Last year, 1,600 died from two lesser heat episodes, according to official figures.
"Currently there is a 50% chance we could see temperatures top 40C and 80% we will see a new maximum temperature reached."
- Paul Gundersen, Chief Met Office Meteorologist
