The heatwave in western Europe will peak on Monday and Tuesday before highest temperatures are confined to France, Spain and Portugal later in the week. Western Europe is sweltering under a heat dome – warm air trapped under a strong area of persistent high pressure. The first major heat event of 2026 has come unusually early: temperatures in May rarely rise above 30 degrees as far north as France and Germany, large parts of which are experiencing temperatures 10-15 degrees above the climate average. France has already broken its May record of 30.5 degrees, as temperatures have peaked in the low 30s each day since Thursday, and higher is still to come. Temperatures more than 10 degrees above average are expected in places until the weekend and parts of the southwest could reach 37-38 degrees.Spain and Portugal have not threatened their May records (44.4 degrees and 40 degrees respectively) and are unlikely to do so, but they will have the most prolonged hot spell. Across the end of May and first part of June, temperatures will remain widely 5-10 degrees above average across Iberia. Temperatures have peaked in the high 30s each day since Thursday and are forecast to continue doing soEngland, Wales and Northern Ireland recorded their highest temperatures of 2026 on Sunday, which was also the UK’s hottest May day for at least 79 years.Kew Gardens in west London recorded 32.3 degrees, Cardiff 27.4 degrees and Armagh 23.4 degrees.Scotland reached 23.5 degrees in Edinburgh, just 0.1 below the record of 23.6 degrees set in Aboyne on May 1st.The first area of the UK to hit the heatwave threshold was Santon Downham in Suffolk, which reached the criteria of recording temperatures of more than 27 degrees for three consecutive days at 11.30am on Sunday.The other areas officially in heatwave conditions are Heathrow, Kew Gardens and Northolt in London, Benson in Oxfordshire, Brooms Barn in Suffolk and High Beach and Writtle in Essex.Temperatures could rise again on Monday, with possible highs of between 33 and 34 degrees.The climate crisis is increasing the likelihood of extreme heat. The French national weather agency, Météo-France, said periods of exceptional heat were to be expected “more and more often and more and more prematurely, and to be more and more intense”.A UK Met Office spokesperson said: “Breaking the 32.8 degrees May record is around three times more likely now in our current climate than it would have been in natural climate conditions before the Industrial Revolution.“What was around a one-in-100-year event is now around a one-in-33-year event.”The Met Office sets the UK’s criteria for a heatwave, which vary by region. In London and its surrounding counties, a heatwave is defined by temperatures reaching or exceeding 28 degrees on three consecutive days. – Guardian