The government has issued a warning that those vulnerable to dehydration should take care during this week's anticipated heatwave.
Temperatures in Britain on Sunday were in excess of 32 degrees C and have been forecast to continue along the same lines until Wednesday.
A heatwave in 2003 caused deaths in London to rise by 60 per cent amongst the over-75s, according to the BBC.
Liam Donaldson, the chief medical officer, warned: "Although severe heatwaves are uncommon in England, the experience across north-west Europe in 2003 is a reminder that heat can be fatal, or at the very least can cause unnecessary discomfort."
He advised: "The elderly are particularly vulnerable and it is important that those aged over 75, especially those who live alone or in care homes, take precautions to avoid heat exhaustion and heat stroke."
The warning said that people in London, the West Midlands and the south east are most likely to be affected.
Thunderstorms have been predicted by the Met Office once the pressure breaks on Thursday, although the temperature looks likely to remain warm all week.