Unrivaled March heat wave expected to torch Phoenix records, produce highs over 100

PHOENIX – A Phoenix heat wave of unprecedented intensity for March is set to torch the record book and produce the year’s first triple-digit temperatures.

The historic late-winter weather is due to consecutive high-pressure systems, according to meteorologist Chris Kuhlman of the National Weather Service (NWS) in Phoenix.

“There is a pretty strong high-pressure system that’s set up just west of California right now. That’s going to lead to near-record temperatures today and Friday, but that system is going to weaken into this weekend,” Kuhlman told KTAR News 92.3 FM on Thursday morning.

Still, Phoenix temperatures are expected to reach the low 90s from Thursday to Sunday, about 15 degrees above normal for mid-March. And the forecast highs of 94 degrees on Friday and Sunday are above the daily records of 92 for those dates.

The second high-pressure system is expected to drive temperatures up even more, possibly producing highs never seen before this early in the year.

Strong high pressure will build across the region mid-late week. Lower desert temperatures will reach the 90s by the end of the week and then exceed 100 degrees next week, likely setting new all-time March records and the earliest 100°F occurrence in Phoenix. #azwx #cawx pic.twitter.com/EfCHK15XCM

— NWS Phoenix (@NWSPhoenix) March 10, 2026

“This one is going to be unusually strong and large, and it’s going to eventually, by Wednesday, just park itself directly over the desert Southwest with record strength, and it will easily break daily records — some days, 5 degrees above. We may even have a record broken like 8, 9, 10 degrees above the previous records,” Kuhlman said.

How long will Phoenix heat wave last?

The Phoenix heat wave is expected to last through the end of winter and into early spring, which starts on March 20.

“Beyond like eight, nine, 10 days, it’s hard to tell how much longer, but it should hopefully break down,” Kuhlman said. “The worst of the heat right now looks to be probably next Thursday, Friday and Saturday, where we’re looking at temperatures around at least 100 degrees.”

If it reaches at least 100 degrees next week, it would be the earliest triple-digit day ever recorded in Phoenix.

Until now, the weather station at Phoenix Sky Harbor International Airport, which the NWS uses for the city’s official readings, has recorded a triple-digit high just once in March. That was when it hit 100 degrees even on March 26, 1988.

We are currently forecasting the earliest occurrence of 100+ degrees on record in Phoenix next week. A 100 degree high has only occurred once before in March of 1988. We could also see the earliest occurrence of a 70 degree low late next week. #azwx pic.twitter.com/G6v6UN2ciR

— NWS Phoenix (@NWSPhoenix) March 12, 2026

“The highest temperature we’ve ever had in April is 105 degrees,” Kuhlman said. “We could actually be a degree or two warmer than that possibly. So, we might even break all-time record temperatures, not just for March, but even if you consider April temperatures, too.”

The average for the first day at 100 degrees in Phoenix is May 2.

Phoenix heat wave comes at peak time for outdoor activities

While Valley residents regularly cope with temperatures of 110 degrees and higher in the summer, they generally have time for their bodies to acclimate as temperatures rise through the spring. They’ve never seen this kind of heat this early in the year.

Furthermore, March is a popular time for people to get outside and enjoy activities like spring training baseball, golfing and hiking. Winter visitors who regularly flock to Arizona for a break from colder climes could be unprepared for the extreme heat.

“If it’s going to be this hot, just when it’s probably from 11 a.m. through 6 p.m., stay inside as much as you can. Hopefully, air conditioner is working and running. That’s the best suggestion I would make,” Kuhlman said.

Kuhlman added that NWS meteorologists have been discussing the possibility of issuing an extreme heat warning to alert the public to the health risk, something that has never been done before in March.

“It’s not quite meeting our criteria right now, but it’s right on the edge,” he said.

In addition to raising awareness, such a warning would trigger the daytime closure of some or all hiking trails at Camelback Mountain, Piestewa Peak and South Mountain in Phoenix.

KTAR News 92.3 FM’s Colton Krolak contributed to this report.

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