05/07/2026 – Weather in Cornwall

How hot Cornwall gets this week, day by day

If the last few weeks have kept you reaching for a jumper, the outlook has shifted. The South West is heading into a stretch of increasingly hot weather, with temperatures pushing towards 30°C by Monday and warm nights to follow.

Sunday starts warm and hazy

Patchy low cloud is lingering across the region first thing, but it should brighten through the morning. After that, very warm and hazy sunshine develops in light winds, though some coasts hold on to their low cloud. The forecast puts Sunday’s high at 27°C.

The evening stays bright and warm before low cloud moves back in overnight, bringing mist and fog patches to some areas. It stays dry and warm into the small hours, with temperatures holding around 15°C.

Monday looks like the turning point

Low cloud burns back during the morning to leave sunny skies behind. In that sunshine and light winds it feels very warm, and the regional high climbs to 30°C.

The heat builds through the week

From Tuesday to Thursday the forecast stays dry and increasingly hot. There is plenty of strong sunshine and light winds in the mix, and some warm nights to go with it.