Attribution study links heatwave directly to fossil fuels
World Weather Attribution released a rapid analysis on Wednesday concluding that the ongoing heatwave affecting the US Northeast and eastern Canada would have been "virtually impossible" in a world without climate change caused by fossil fuel burning. The scientists analyzed wet bulb globe temperature data — a measurement combining heat, humidity, wind, and solar radiation — and found the five-day heat stress peak had a 0.5% annual probability in today's climate but was effectively zero before the Industrial Revolution.
Over 1,500 temperature records broken in June
NOAA data showed that daily high temperature records were matched or broken more than 1,500 times across US weather stations in June 2026 alone. Philadelphia hit 104°F, forcing cancellation of the city's July Fourth parade and the planned replica of George Washington's tent outside Independence Hall. Washington D.C. recorded a historic daily high of 103°F, cancelling its own parade. New York City opened 1,200 cooling centers as heat-related emergency room visits spiked 250% above baseline.
European heatwave declared worst on record
The heatwave simultaneously scorching western Europe was declared the most severe and widespread ever recorded for the region, according to researchers at Imperial College London. The UK recorded its hottest June temperature ever at 36.7°C (98.06°F) in Somerset. Almost half of Europe's 850 largest cities were experiencing their worst-ever heat stress. The Met Office extended red heat-health alerts across England and Wales. Scientists noted that a comparable heatwave in 2003 would have been 2°C cooler due to lower global heating at the time.