[REVISION HISTORY]

US heat dome causes record temps, rescues, and farm impacts

Updated 18 times since CLSTR started tracking revisions of this situation.

What changed

2026-08-08 15:01 UTC → 2026-08-15 09:56 UTC · added ~~removed~~

~~Heat~~ US heat dome ~~drives~~ causes record temps, ~~alerts,~~ rescues, and farm impacts

The ~~slow‑moving high‑pressure~~ slow-moving high-pressure heat dome over the western United States has kept temperatures at record levels, with readings up to 122 °F in much of California and a projected 126 °F in Death Valley. More than 40 million people are under heat alerts, including about 12 million in the highest‑risk category. Early July saw ozone and dust in the San Joaquin Valley and beach‑water advisories in Los Angeles County after bacterial tests exceeded standards. The dome moved eastward, producing record highs in Salt Lake City (≈109 °F) and Billings, Montana (≈111 °F) and prompting extreme‑heat warnings across 23 states, with heat‑index values of 115 °F forecast for parts of the Northeast. Wildfire risk surged in Utah and Arizona. Southern California received extreme‑heat warnings for Los Angeles‑Oxnard, the Bay Area and Central Coast, with temperatures between 90 °F and 110 °F. Monsoonal moisture brought higher humidity, isolated thunderstorms and on‑shore winds from the remnants of Tropical Storm Elida. Red‑flag fire alerts and public‑safety power shutoffs were announced for the Bay Area, Central Coast and several Southern California counties; PG&E prepared community resource centers. Cooling centers opened in Los Angeles, Orange County and other communities, and health officials urged hydration, air‑conditioned shelter and checking on vulnerable neighbors. maintained record-breaking temperatures. By early ~~August~~ August, the National Weather Service issued Extreme Heat Warnings ~~covering~~ for desert zones ~~such as~~ including the Indian Wells Valley, ~~Mojave and~~ Mojave, Coachella, ~~Imperial County (104‑117 °F),~~ and the Phoenix ~~metro area (above~~ metropolitan area, with temperatures exceeding 110 ~~°F) and~~ °F. In Southern California, the ~~Reno‑Carson City‑Minden region (98‑102 °F). On August 5, lifeguards in Los Angeles County reported~~ heat wave drove a record 1,950 ocean ~~rescues. That day~~ rescues in Los Angeles County on August 5, as high temperatures and six-foot swells created dangerous rip currents. Simultaneously, health officials ~~also~~ issued ~~water‑quality~~ water-quality warnings for several ~~piers~~ piers, including Venice and Santa Monica, after bacterial levels exceeded state ~~standards,~~ standards. Agricultural impacts have become significant. In the Imperial and ~~Governor Gavin Newsom deployed firefighters~~ Central Valleys, triple-digit heat has prompted warnings for outdoor workers. In Tulare County, dairy operators are implementing cooling measures to ~~assist with heat‑related emergencies.~~ mitigate cattle mortality. By ~~late July,~~ mid-August, the heat dome's influence expanded, with meteorologists estimating 70–80 million people were under extreme-heat warnings. This has forced shifts in daily routines for construction and agriculture, alongside spikes in energy demand. While some regions, such as the Midwest, faced concurrent threats of severe storms and high heat indices, the Desert Southwest experienced a mix of extreme ~~conditions persisted.~~ heat and isolated thunderstorms. In Imperial County, wind-blown dust triggered air quality alerts. A cold front is expected to bring cooler, milder temperatures and lower humidity by late August.

Versions

Only revisions since CLSTR began indexing content versions appear here. Select a version to see what changed compared to the one before it.