The US Just Had Its Hottest Month Ever — Here's What Happened
July 2026 was the hottest month ever recorded in the lower 48 states, breaking a record that goes back 132 years. NOAA, the government agency that tracks weather and climate, says the average temperature for the month was 76.9°F. That's 3.3°F above what was normal for the 20th century. The previous July records were set during the Dust Bowl in 1936 and again in 2012. US temperature records begin in 1895. NOAA NCEI
The heat touched every corner of the country. Every state in the lower 48 landed in the warmest third of its own July history, and none came in near or below average. Thirteen states had one of their five warmest Julys ever. Wyoming stood out: its July temperature was 5.1°F above normal, beating its previous July record from 2007 by nearly a full degree. It was Wyoming's warmest July — and its warmest month of any kind on record. NOAA NCEI
What made this July unusual was not just how hot the days got, but how warm the nights stayed. Overnight lows across the lower 48 averaged 64.2°F, which is 3.7°F above the 20th-century average and the warmest monthly nighttime temperature on record. Daytime highs, while elevated, ranked only sixth-warmest. That gap matters. When nights stay hot, people, crops, and power systems never get a chance to cool down and recover, so heat stress builds up day after day even if no single afternoon sets a record. NOAA NCEI
Even though July 2026 set the monthly average record, the record for the hottest single day still belongs to July 2024. Scientists make an important distinction here: a record monthly average means the heat was persistent, staying high around the clock, rather than spiking on one or two extreme days.
During the month, three separate "heat dome" events settled over the country, according to NOAA data. A heat dome is a large zone of high pressure in the atmosphere that traps warm air underneath it, like a lid holding heat in a pot. Heat domes are common in American summers, but having three of them line up in a single month helped keep temperatures high for weeks. The Guardian
Rainfall was below average too. The lower 48 averaged 2.55 inches of rain in July, 0.23 inch below the 20th-century average, putting the month in the driest third of the 132-year record. Even so, major flash flooding hit the Texas Hill Country and eastern New York. This fits a pattern scientists have documented: a warmer atmosphere can hold more moisture, so when rain does fall, it can come down harder, even if the total amount of rain for the month is low. NOAA NCEI
Alaska and Hawai'i, which are not part of the lower 48, told a different story. Alaska averaged 51.8°F, almost a degree below its 1925–2000 baseline, making it the state's coldest July since 2008. Hawai'i averaged 69.4°F, slightly above its 1991–2020 normal. The contrast shows that the record for the lower 48 was driven by a specific weather pattern over the continent, not a uniform trend everywhere at once. NOAA NCEI
The broader context here is that this one month fits into a much longer warming trend. As of March 2026, the lower 48 had just experienced their warmest 12-month stretch on record. February 2026 averaged 40.4°F, which is 6.6°F above the 20th-century mean, making it the second-warmest February ever. NOAA's global data for June 2026 showed temperatures 2.0°C (3.6°F) or more above average across the lower 48, the Arctic, parts of Asia, and the North Pacific. NOAA NCEI In other words, July's record did not come out of nowhere — it built on months of unusual warmth across land and ocean alike.
Looking ahead, July 2026 now pushes aside two years that have long served as reference points in American climate conversations. The 1936 Dust Bowl July has been the go-to example of extreme heat in US history, and being surpassed by this margin makes the gap between past climate events and today's warming noticeably smaller. The record-warm nights in particular carry real-world consequences that extreme daytime records alone do not. When temperatures do not drop at night, air conditioning demand stays high around the clock, livestock and crops never get relief from heat stress, and people with health vulnerabilities face longer exposure. The fact that the single-day heat record still belongs to 2024 also suggests something scientists have been tracking: monthly averages are now climbing faster than one-day extremes, meaning the overall baseline of heat is rising even when no single day breaks a record.
