Unseasonably warm Valley weather to continue through weekend before cooldown

PHOENIX – The ongoing stretch of unseasonably warm metro Phoenix weather will last through weekend, but a cooling system is looming.

A large ridge of high pressure has been keeping Valley’s high temperatures in the upper 70s and lower 80s since the calendar turned to December, about 10 degrees above normal for this time of year. In fact, Phoenix set a record for the date on Tuesday with a high of 83, topping an 84-year-old mark by 2 degrees.

The ridge is expected to linger for several more days before weakening, according to Ted Whittock, a meteorologist with the National Weather (NWS) Service in Phoenix.

“This sort of blocking pattern that we’ve had over the Western U.S. is finally going to start to break down,” Whittock told KTAR News 92.3 FM on Friday morning. “Looks like we’ll have a pretty quick moving weather system during the middle of next week that will really dry things out and cool things off.”

The Phoenix-area forecast calls for highs in the upper 70s on Friday and slightly cooler over the weekend, “just trending down a few degrees each day,” Whittock said.

But on Tuesday, the mercury is expected to peak at around 70 or a bit lower, which would be in the normal range for this time of year.

Cooling system not expected to end Phoenix dry spell

However, the cooling system isn’t expected to end a Phoenix dry spell that has lasted for more than 100 days.

“What it will act to do is really dry things off, and that will allow us to see some pretty cool overnight temperatures, especially Tuesday night into Wednesday. Some of the more rural locations will probably be flirting with the freezing mark, around 32,” Whittock said.

Phoenix Sky Harbor International Airport, which the NWS uses for the city’s official readings, hasn’t received measurable rain since Aug. 22.

KTAR News 92.3 FM’s Jim Cross contributed to this report.

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