SCIENCE · VERIFIED DEVELOPMENT
Unseasonable Heat Wave Brings Record-Breaking Temperatures to South-Central US
WHY IT MATTERS
The extreme heat wave highlights the ongoing impact of climate change, with the contiguous US experiencing its warmest June through August in a 132-year record, according to NOAA.
What happened
A heat dome developed over the south-central United States on September 15, 2026, causing unseasonable and record-breaking warmth. The area of high pressure pushed hot air toward the surface, trapping it and suppressing clouds and precipitation.
This led to temperatures approaching or exceeding 40 degrees Celsius (104 degrees Fahrenheit) in some areas. Over 41 million people were under an extreme heat advisory, watch, or warning, with several locations setting new daily high temperature records.
Dallas, Texas, reached 101ºF (38ºC), while Memphis, Tennessee, and Nashville, Tennessee, reached 99ºF (37ºC) and 100ºF (38ºC), respectively. Nashville broke its daily-high record from 1927 and set a record-high minimum temperature of 75ºF (24ºC) the day before.
PRIMARY SOURCES
Summer Goes Out With a Heat Dome
NASA · NASA media usage guidelines; third-party material excluded