Friday’s rainy start was the first part of “a theater piece in two acts,” said KPLU weather expert Cliff Mass. “The first act happened this morning.”
The showers that doused the northwest overnight will return in the afternoon, Mass says, accompanied by “all kinds of thunderstorms and heavier rain. ”
He predicts those will start revving up sometime between 3 p.m. and 4 p.m. “And I would expect rain around dinnertime into the early evening.”
Mass says the rest of the weekend looks a bit cooler than it’s been recently but still quite pleasant. Friday is the exception.
Coolest Friday
“We will have the coolest day of the whole summer – so far at least,” he said. “Temperatures only getting up into the upper 60s at the most.”
But he says the trough of low pressure that’s bringing the thunderstorms will move through very quickly, allowing the weather to improve early Saturday.
Sunshiny Saturday
“There’ll be some clouds in the morning, but those will burn off fairly rapidly with temperatures getting up maybe into the mid-70s -- upper 70s in some places," Mass said. " So, big improvement, sun’s back.”
The mercury will keep rising on Sunday, Mass predicts, with temperatures reaching 80 or even the low 80s. There will be another upper level trough moving in but he says it will be weak with a much lower chance of precipitation.
“Maybe some increased clouds and a few sprinkles, particularly in the mountains,” he said. But not much of the wet stuff in the lowlands.
“And as we go into the middle of next week, that trough will move through, the ridge (of high pressure) will again re-form. And temperatures should surge up into the 80s,” Mass said.
But he says the hot temps that have made this summer so dry appear to be a thing of the past.
“There are no 90s in the forecast as far as we can see right now,” he said.
Fire Outlook: Risky
Friday’s rains are a mixed blessing for the fire outlook in the state. The wet weather and cloudy skies are helping tamp down some of the worst blazes. But the storms that are coming through this afternoon and evening promise to bring a lot of lightning with them, Mass says, increasing the risk that new fires will start.
“And if there’s not enough rain with that lightning, there’s potential for more fires,” Mass said. “So it cuts both ways. And it’s unclear which way it will go.”
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The weekly KPLU feature "Weather with Cliff Mass" airs every Friday at 9 a.m. immediately following BirdNote, and twice on Friday afternoons during All Things Considered. The feature is hosted by KPLU Environment Reporter Bellamy Pailthorp. Cliff Mass is a University of Washington Professor of Atmospheric Sciences, a renowned Seattle weather prognosticator, and a popular weather blogger. You can also subscribe to a podcast of “Weather with Cliff Mass” shows.
