Phoenix, AZ – A prolonged stretch of dangerous heat will take hold across Arizona and southeastern California starting late Wednesday and intensifying Thursday, with temperatures climbing as high as 109°F and lasting through Sunday evening.
According to the National Weather Service in Phoenix, an Extreme Heat Warning begins at 11 a.m. Wednesday for areas along the Colorado River including Parker, Blythe, and the Imperial Valley, then expands across the Phoenix metro, Yuma, and south-central Arizona at 11 a.m. Thursday. Afternoon highs between 100 and 109 degrees are expected, with a “major heat risk” designation in densely populated areas like Phoenix, Mesa, and Chandler.
Communities including Yuma, Casa Grande, Gila Bend, and Quartzsite will see prolonged exposure to triple-digit heat, while urban infrastructure in Phoenix will intensify conditions during peak afternoon hours. Cooling demand is expected to surge, increasing the risk for heat-related illness, especially among vulnerable populations.
Residents are urged to limit outdoor activity to early morning or late evening, take frequent breaks in shaded or air-conditioned spaces, and stay hydrated. Cooling centers are available in some areas, and assistance can be reached by dialing 2-1-1.
The heat wave will persist through Sunday night with little relief, and additional alerts may be issued if extreme temperatures continue into early next week.
