Dangerous heatwave set to intensify across the US
A prolonged and dangerous heatwave is expected to intensify and spread across the eastern half of the US this week, with heat indices potentially reaching 46°C.
The US National Weather Service has warned of a dangerous heatwave that will intensify and expand across the eastern half of the country this week, bringing extreme temperatures through the Fourth of July holiday weekend. Temperatures ranging from 32°C to 40°C, combined with high humidity, could push local heat indices up to around 46°C.
The heatwave is likely to peak in the Midwest and Mississippi Valley from Tuesday to Thursday before moving into the Ohio Valley and East Coast on Thursday and into the weekend. The agency noted that there will be little to no overnight relief, with nighttime temperatures only dropping into the 20s Celsius.
This stretch of record-breaking heat from the Midwest to the East Coast is particularly dangerous not only because of the soaring daytime highs but also due to its multi-day duration and record-warm morning lows, which deprive areas of nighttime cooling. The NWS emphasized that such prolonged heatwaves are among the deadliest weather events in the US, as their impacts are less visible and build over time.
The warning comes after an early-summer heatwave gripped much of Europe in late June. Parts of France, Spain, and Germany topped 40°C last week, straining health services amid a spike in heat-related emergencies. WHO Director-General Tedros Adhanom Ghebreyesus reported that over 1,300 excess deaths recorded between June 21 and June 28 in Europe were linked to high temperatures. He also announced that the WHO has partnered with FIFA to help protect players, staff, and fans at the 2026 World Cup in the US from the scorching temperatures.
