The UK Health Security Agency has issued a yellow heat-health alert for the South West.
The alert is in place from 2pm today until 5pm on Wednesday May 27.
Officials say the heat could increase pressure on health services and pose a higher risk to people aged over 65 and those with existing health conditions.
People are advised to keep homes cool, avoid the sun between 11am and 3pm, wear suitable clothing outdoors and drink plenty of water.
The UKHSA is also warning of risks around open water, including cold-water shock, and is urging people to swim only at supervised locations.

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