Extreme Heat Warnings Issued Across Southwest US
The National Weather Service has issued extreme heat warnings and advisories across parts of the Southwest United States, including Southern California, Nevada, and Arizona, from Tuesday, September 8, through Thursday, September 10. In Phoenix, an Extreme Heat Warning is in effect from 10 a.m. Tuesday to 8 p.m. Thursday, with highs near 109°F (43°C) on Tuesday and slightly lower temperatures expected on Wednesday and Thursday. Southern Nevada, including Las Vegas, is under a similar warning on Thursday, with temperatures forecasted to reach 105–110°F (40–43°C). Death Valley and the Colorado River Valley may experience highs between 112–116°F (44–47°C). Los Angeles and Orange counties are under a heat advisory from 10 a.m. Wednesday to 8 p.m. Thursday, with temperatures ranging from 85–105°F (29–41°C). The heat is attributed to a high-pressure system moving west, reducing monsoon rain chances and driving temperatures upward. Source time: Tue, 08 Sep 2026 13:56:02 GMT.