Heat Advisories issued by 16 National Weather Service (NWS) forecast offices cover portions of 12 U.S. states from September 14 through September 16, 2026, with heat index values forecast to reach 46°C (114°F) in southern Texas. The advisories extend from Texas and Oklahoma through the Lower Mississippi Valley and Mid-South into Indiana and Kentucky.
Extreme Heat Warnings and Heat Advisories were issued across parts of the central and southern United States, the Southwest and California on September 8, 2026. The National Weather Service (NWS) forecast heat index values up to 44°C (112°F) in parts of Arkansas and Oklahoma and temperatures up to 47°C (116°F) in Death Valley and the Colorado River Valley, with several western alerts continuing through September 11.
Heat Advisories covered a broad corridor from the southern Plains and lower Mississippi Valley through the Midwest, Ohio Valley and parts of the Mid-Atlantic on September 1, 2026. National Weather Service (NWS) offices forecast heat indices from around 37.2°C (99°F) to 43°C (110°F), with several multi-day products citing limited overnight relief as a factor in maintaining the advisories.
Multiple heat advisories were issued across portions of California, Oregon, Washington, and Nevada on June 15, 2026. Temperatures are forecast to exceed 40°C (104°F) and could reach up to 44.4°C (112°F) in Trinity County, California.
