24/06/2026 – Weather in Cornwall

38°C forecast for Cornwall and the South West this week

The next few days are going to be hot, and Thursday could be the hottest of the lot.

Forecasters say Cornwall and the wider South West are in for a spell of dry, sunny and very hot weather running from Wednesday 24 June through to Sunday 28 June. Temperatures could reach as high as 38°C in the hottest parts of the region, and the nights are set to stay warm and muggy, making it harder to cool down after dark.

What to expect today

Wednesday stays dry with strong sunshine. After a warm start the temperature climbs quickly to bring a very hot afternoon, with light winds and high humidity. The regional maximum is 35°C.

There is little relief overnight. The evening stays dry and very warm with some late sunshine, leading into a very warm and muggy night. The overnight minimum is around 20°C.

Thursday turns hotter still

Thursday opens dry, warm and sunny before turning hotter again. Extreme heat is forecast to continue alongside high humidity, with the regional maximum reaching 38°C. It may cloud over a little at times during the afternoon.

How the rest of the week looks

Friday is set to be another hot day before temperatures slowly come down over the weekend. There is plenty of dry and sunny weather in the outlook, though thunderstorms are a risk at times.

How to keep cool in the heat

If you feel the heat, the next few days are the ones to plan around. A little preparation makes a big difference.

Keep your home cool

Close curtains and blinds on the sunny side of the house during the day to keep the heat out. Open windows overnight and early in the morning when the air is cooler, then shut them again before the sun is back on the glass. A fan helps move the air around, though it does little once the room climbs above body temperature.

Stay on top of water

Drink more than you think you need, and keep sipping through the day rather than waiting until you feel thirsty. Water is best. Go easy on alcohol and very sugary drinks, which leave you more dehydrated.

Avoid the worst of the sun

The sun is strongest between 11am and 3pm, so stay out of it where you can. If you are heading out, take water, wear a hat and loose clothing, and stick to the shade. Move walks, the school run and any outdoor jobs to the early morning or the evening.

Check on the people who feel it most

Older neighbours, young children and anyone with a health condition are far more at risk when it gets this hot. A quick knock on the door or a phone call to make sure they are coping costs nothing.

Never leave anyone in a parked car

Cars heat up frighteningly fast, even with a window cracked open. That goes for children and pets, even for a couple of minutes.

Know the warning signs

Heat exhaustion can come on quickly. Watch for heavy sweating, dizziness, a headache, cramps, feeling sick or being very tired. Move the person somewhere cool, get them sipping water and help them cool down. If they do not improve within 30 minutes, or they become confused, stop sweating or lose consciousness, call 999.