UK Set for Warm Spell With Temperatures Reaching 26C on Wednesday

Temperatures soared to 24.8°C in Mona on the island of Anglesey on Tuesday, setting the warmest April 7 on record and the highest reading of 2026 so far. Wednesday is the final act of that warmth before conditions shift markedly.

Parts of the UK could see temperatures as high as 26°C on Wednesday, before conditions turn markedly cooler later in the week. Fine and sunny weather is dominating for many as warm air is drawn northwards across the UK. Conditions are peaking Wednesday, when lighter winds are making it feel even warmer, particularly across central and southeast England, where temperatures could climb to 26°C. These figures are well above the seasonal average for early April, which typically sits in the mid-teens.

London could bask in temperatures as high as 26°C on Wednesday. Forecasters at the Met Office say warm air moving north across the UK will bring a "brief but notable" spell of very warm weather for early April, with lighter winds helping temperatures climb across London and the South East.

Not everyone is sharing in the warmth. Northern Ireland and parts of western Scotland are facing cloudier skies and the risk of afternoon rain, with breezy conditions around some coasts keeping the heat at bay there.

The biggest immediate health risk is pollen. The Met Office has issued a red alert for hay fever sufferers in Wales, and England is also set to see very high pollen counts. This unusual heat is also driving a high pollen forecast for London and southern England. Heat-related mortality in the UK rises significantly around 29°C, making the rapid onset of this early-season heat a particular concern. The combination of unseasonably high temperatures and elevated tree pollen represents a compounded burden for the roughly 13 million hay fever sufferers in England and Wales.

The warmth is short-lived. The Met Office warned of another big change on Thursday, when temperatures are expected to fall to between 10°C and 13°C. The contrast matters because it shows how unsettled the current forecast remains: a brief burst of warmth is enough to drive pollen levels higher, even while a colder shift is already close behind. Rain followed by cooler and showery weather will move southeastwards across the UK throughout Thursday, with the southeast remaining dry and warm until later in the day. The weekend looks unsettled, with further bands of rain and showers and temperatures near or occasionally a little below average.

Wednesday is set to feel even warmer, particularly in central and south-east England, where temperatures could reach 26°C, which is "well above" the early April average of 12°C to 15°C. The Met Office noted: "Here we've had the warmest 7th April on record and the highest temperature of 2026 so far. We're very likely to see higher temperatures as we move through the rest of spring and towards summer."

Spring is the fastest warming season in the UK due to climate change. The Met Office estimates the global temperature for 2026 will be around 1.46°C above the pre-industrial average, which would make it the fourth year in a row to exceed 1.4°C. Wednesday's peak, extraordinary for early April, is the kind of data point forecasters are adding to an increasingly unusual seasonal record. Thursday's return to single-figure overnight temperatures will bring its own adjustment, with the speed of the swing, roughly 13°C in 24 hours, as notable as the warmth itself.