A large heat dome is forecast to generate temperatures exceeding 38 °C (100 °F) across much of the central and eastern United States starting June 20, 2025, with high humidity compounding heat risks for over 200 million people.
At least four elderly women died of suspected heatstroke on June 17, 2025, in Japan’s Kanagawa, Shizuoka, Saitama, and Gunma Prefectures. More than 60 monitoring stations recorded temperatures at or above 35 °C (95°F). Temperatures are expected to rise until June 20, and a heat advisory is in place.
The National Weather Service issued an Extreme Heat Watch for parts of southern Arizona and far southeastern California from the morning of June 14 through the evening of June 16, 2025. Affected areas include the lower deserts of Arizona and southeastern California, where daily maximum temperatures are expected to reach 40°C to 46°C (104°F to 115°F).
Spain recorded its hottest May day on May 30, as the national average temperature exceeded 24 °C (75 °F) due to a hot air mass from North Africa. Some regions experienced temperatures over 10 °C (18 °F) above normal, marking the highest May temperature since records began in 1950.
A ridge of high pressure over the western United States is bringing unusually hot and dry conditions, with record temperatures expected from May 30 to 31, 2025. The hottest areas include southern Nevada, southeast California, and northwest Arizona. Cooler air and possible light rain from a Pacific cold front and Tropical Storm Alvin are forecast to arrive by early June.
A Heat Advisory has been issued for multiple regions in California, including the North Bay, East Bay, South Bay, Santa Cruz Mountains, and Central Coast, for Friday, May 30, 2025, due to forecast temperatures reaching up to 41 °C (105 °F).
A record-breaking heatwave affected Iceland from May 6 to 15, 2025, with temperatures reaching 26.6°C (79.9°F) at Egilsstaðir Airport and setting a new national May temperature record. The 10-day event was described by the Icelandic Meteorological Office as the most significant May heatwave in the country’s meteorological history.
The United Arab Emirates recorded 51.6°C (124.9°F) in the town of Sweihan, Al Ain Region, Emirate of Abu Dhabi, at 13:45 LT (09:45 UTC) on May 25, 2025, breaking the country’s May temperature record for the second consecutive day, just 0.4°C (0.7°F) below the all-time national maximum.
Havana’s Casablanca weather station recorded 38°C (100.4°F) on May 20, 2025, setting a new May temperature record. This surpassed the previous high of 37.3°C (99.1°F) recorded on May 19, 2024, according to Cuba’s Institute of Meteorology (INSMET).
Camp Mabry broke a 100-year-old daily heat on Thursday, May 15, 2025, as an early-season heat wave caused multiple daily heat records to break across south-central Texas. The heat wave is forecast to continue through the weekend into the next week, with some areas expected to see the highest May temperatures on record.
