Phoenix, Arizona — A rapid daytime heat surge is set to grip the Valley within hours, pushing temperatures into the low 90s by mid-afternoon and creating early-season heat stress across Phoenix, Mesa, Glendale, Scottsdale, and Tempe.
According to the National Weather Service, temperatures will climb from the upper 60s this morning to around 91°F between 2 p.m. and 5 p.m. Friday, with dry air and clear skies accelerating heating across central Arizona.
This is part of a broader system building high pressure over the Southwest, allowing strong solar heating and minimal cloud cover to drive temperatures even higher into the weekend.
The most immediate impact hits during the afternoon commute, when pavement temperatures spike and heat radiates off roadways like I-10 and Loop 101. Drivers may notice vehicle strain in stop-and-go traffic, while outdoor workers face rapid dehydration risk within 30 to 60 minutes of exposure.
Low humidity near 30 percent will increase evaporation, drying soils and creating dusty conditions in open areas west of Phoenix and near construction zones. Heat will concentrate in urban corridors and low-lying neighborhoods, especially in dense areas of downtown Phoenix.
Residents should limit outdoor activity during peak heat, drink water frequently, and avoid leaving pets or people in vehicles where temperatures can rise above 120°F within minutes.
Temperatures will peak again Saturday between 3 p.m. and 6 p.m. near 95°F, increasing heat exposure risk heading into the weekend.
