Hot weather returning to Tri-Cities

Don’t put away your swimsuits and other hot weather gear just yet.

Temperatures could climb into the mid-90s this weekend in the Tri-Cities, according to the National Weather Service. Normal highs for mid-September in the Tri-Cities are about 80 degrees.

A “monster ridge” of high pressure that had parked itself over the West Coast, contributing to record high temperatures and drought conditions, has returned, said Nic Loyd of Washington State University’s AgWeatherNet.

“For a short time, cool, dense air moved in and displaced that persistent ridge,” he said. “Now it’s returning from southwest of us. There’s no question — the monster ridge is back.”

Last week, a cluster of churning tropical storms in the Pacific Ocean helped break up the ridge, bringing cooler temperatures and some rain to the Mid-Columbia, Loyd said. But the massive, advancing high-pressure system tells meteorologists that the shift to cooler temperatures was only temporary, he said.

“Unfortunately, I think there’s a strong chance that dry conditions and above-average warmth will extend through winter,” Loyd said.

The high Friday in the Tri-Cities could be in the low 90s. Saturday should be warmer, with highs from 95 to 97 degrees, according to the weather service. Sunday, highs could drop back into the high 80s.

By Monday, highs should be falling back to a more seasonable 75 to 77 degrees, at least for a time.

Annette Cary: 509-582-1533; acary@tricityherald.com; Twitter: @HanfordNews