Europe's Fifth Heat Wave of 2026 Pushes Temperatures Past 40°C, NASA Data Shows

Western Europe has been hit by a series of record-breaking heat waves in 2026, starting with an unusual heat dome in May and continuing through a fifth heat wave in mid-August that pushed temperatures above 40°C (104°F) across a broad area, according to NASA Earth Observatory. The heat has often persisted for days or weeks at a time, including overnight, worsening a drought that has gripped the region for months and disrupting water and power supplies, transportation and agriculture.

Records fell by wide margins: London hit 35.1°C on May 26, breaking the previous May record by 2.3°C, according to the UK Met Office. Bordeaux, France, broke its maximum-temperature record on three consecutive days in June, reaching 42.5°C on June 24, per Météo-France, while Slovakia set new national records for both daytime and nighttime highs in August. Europe's Copernicus climate monitoring service reported that combined June and July temperatures in Western Europe were the highest on record.

Preliminary reports suggest the heat may have been associated with about 10,000 excess deaths, including thousands in the UK, France, Germany and Belgium. Researchers point to limited air conditioning as a key vulnerability: only 23% of European homes have it, compared with 90% in the United States, according to International Energy Agency data. The World Health Organization estimates roughly 489,000 heat-related deaths occur worldwide each year, with 45% in Asia and 36% in Europe.

A study published in Lancet Planetary Health in August 2026, led by Stanford researcher Qinqin Kong, mapped where rising heat is likely to become intolerable for people of different ages in the coming decades and found that risks fall disproportionately on older adults. "The human body can tolerate only a limited range of ambient heat. Understanding where, when, and to what extent these limits are exceeded is critical," Kong said, adding that the findings could inform emergency preparedness and health system planning.