UK Health Security Agency has issued an amber heat-health alert for the South West.
The alert is in place from 10am on Tuesday May 26 until 5pm on Thursday May 28.
Officials say the heat is likely to increase pressure on health and social care services and poses a higher risk to people aged over 65 and those with existing health conditions.
UKHSA is advising people to keep homes cool, avoid the sun between 11am and 3pm, wear suitable clothing outdoors, seek shade and use sunscreen.
People are also being warned about risks around open water, including cold-water shock, and are advised to swim only at supervised locations.
Residents are being encouraged to check on vulnerable friends, family members and neighbours during the hot weather.

Rape sentences referred to Court of Appeal
Man pleads guilty to causing serious injury by dangerous driving
Calls grow for rape sentence review
Heat-health alert issued for South West
Stars Appeal trekkers overcome challenges expected and unexpected in India
Hundreds set to take part in Race for Men this Sunday
Catastrophic Bleed Kits Installed at ALABARÉ Homes During Knife Crime Awareness Week
Wiltshire Council celebrates 50,000 children trained through Bikeability programme
