Saturday/Sunday Sizzler

This weekend, Seattle thermometers are poised to climb to a mark they haven’t reached in nearly two years.

90 degrees.

Beginning Saturday, higher pressure to our north and east will turn the winds offshore, allowing warmer air to spill over the Cascades into Western Washington. While the set-up isn’t ideal for extremely hot weather, it should be just hot enough for Seattle to crack 90 by Sunday—for the first time since Aug. 16, 2010.

That, and blow July 8 out of the water as the year’s warmest day.

Hot Seattle
Thanks to clear skies and offshore flow, Seattle will soar to 90 degrees this weekend.

The uptick in temperatures gets underway tomorrow, as sunny skies and northerly winds boost the mercury to the 80-degree mark in the afternoon. The warmer air will also result in higher overnight lows, with many locations not dropping below 60 degrees Friday night.

Things really start cooking on Saturday, with temperatures in Seattle expected to break 80 degrees by lunchtime. By then, a thermal low—an area of low pressure comprised of very hot air—will be firmly entrenched along the coast, helping to send temperatures well into the upper 80s by late afternoon. Sea-Tac Airport may even reach 90—if not, it’ll come pretty darn close.

It’ll warm up a little more on Sunday, as the thermal low moves inland. Highs should make it to 90 degrees from Seattle southward—perhaps even a few degrees warmer in some of the far-flung suburbs like Enumclaw, Covington and North Bend.

Later Sunday night, the winds will shift to the west, blowing off the ocean instead of the land. This should bring about a gradual cooldown for Monday, with morning clouds giving way to afternoon sun. High temperatures will fall back into the upper 70s—territory more familiar for thermometers around Puget Sound.

Until then, the heat is on.