Major to Extreme HeatRisk conditions are forecast to develop across parts of the central United States this week as a strengthening heat dome expands over the region. National Weather Service offices have already issued Heat Advisories across portions of Kansas, Oklahoma, Arkansas, Missouri, Illinois, and Texas, where heat index values are forecast to reach 40 to 42°C (104 to 108°F).
Portugal set a new national May temperature record on May 27, 2026, after Mora reached 40.3°C (104.5°F) during an early-season heatwave, according to the Portuguese Institute for Sea and Atmosphere (IPMA). The reading surpassed the previous May extreme of 40°C (104°F), recorded at Pinhão on May 30, 1953, and matched at Termas de Monfortinho on May 30 and 31, 2001.
France recorded its hottest May day since records began on May 26, 2026, while temperatures climbed to 37.8 °C in southwestern parts of the country on May 28. Multiple stations across France set new all-time May temperature records this week as a prolonged heat dome pushed daytime temperatures into the upper 30s°C (upper 90s°F) and kept nighttime temperatures unusually high across much of the country.
Eleven people have died after getting into difficulty in open water across the UK during a record late-May heat episode. The fatalities include nine children and two adults. The Met Office said 35.1°C (95.2°F) at Kew Gardens on May 26 provisionally broke the UK May and spring temperature record for the second consecutive day.
A record-breaking March heat wave across the southwestern United States accelerated the wildflower bloom cycle in Death Valley National Park, causing peak conditions to occur earlier than typical seasonal patterns. The National Park Service (NPS) reported that lower elevation flowers have already begun setting seed following intense heat and high winds, while the National Weather Service (NWS) reported that hundreds of daily temperature records were set or tied across parts of the region.
Record heat is forecast to persist across parts of the western and central United States through March 25, 2026, with the National Weather Service warning that more than 200 daily record highs could be set as above-normal temperatures spread from the West back into the central and southern Plains. A brief cooldown over parts of the central and eastern U.S. on March 23 is expected to be short-lived. The Storm Prediction Center has issued a severe thunderstorm outlook for Thursday, March 26, covering areas from northeast Missouri to western and northern Ohio.
An intense early-season heatwave pushed temperatures to extreme levels across the southwestern United States between March 18 and 22, 2026, as a persistent high-pressure ridge produced widespread daily and monthly March temperature records. Record heat was reported across Arizona, California, Nevada, and other parts of the western United States.
A historic March heat event affected the U.S. Southwest on March 19 and 20, 2026, setting a new March temperature record in Las Vegas, Nevada, and a new highest March temperature ever recorded in the United States near Martinez Lake, Arizona. Multiple daily and monthly records were also broken across parts of Nevada, California, and Arizona, while authorities in Phoenix closed some hiking trails because of heat risk.
An anomalously early-season heatwave intensified across the western United States on March 18, 2026, with Extreme Heat Warnings in effect for parts of the Desert Southwest and temperatures forecast to expand east into the Rockies and Great Plains by March 20. Highs are expected to reach 40–44°C (104–112°F) in the hottest desert regions, with numerous daily and some monthly March records likely to be broken.
Australia is enduring one of its most intense heatwaves since the 2019–20 Black Summer, with extreme temperatures, strong winds and dry lightning fuelling catastrophic fire danger across multiple states. Emergency-level bushfires have been reported in South Australia and Victoria, while BOM forecasts indicate the threat will intensify through Friday, before cooler air reaches southern regions at the weekend.
