Don’t put your parkas away just yet.
It’s classic April weather this weekend with lots of showers but plenty of sunbreaks, too, according to KPLU weather expert Cliff Mass.
Saturday, in particular, is going to be nice, says Mass, who teaches atmospheric sciences at the University of Washington.
Decent Friday, Then A Dry Start To Saturday
Our Friday will be partly sunny, but showers could increase later in the day as the surface heats up and the cumulus clouds burn off.
"But it should be pretty decent,” he said.
Expect drier conditions “with plenty of sun” on Saturday, said Mass, but it will also be "a little bit cooler than normal" with temperatures only getting into the mid-50s. (Mass says about 60 degrees at SeaTac is the norm for this time of the year.)
Clouds Late Saturday, Then ‘So-So’ Sunday
Later on Saturday, clouds will increase as another Pacific front approaches. Mass predicts rain will probably reach the coast sometime in the afternoon, then move in overnight.
"So in the evening, overnight, there should be lots of precipitation, Saturday night into Sunday morning," he said.
After the front moves through, Sunday will bring typical springtime Northwest weather: "the showers and sunbreaks we love so much around here," Mass said.
He says the strong April sun combined with cold air aloft will intensify the pattern.
"So we’ll see a lot of showers and particularly in a Puget Sound convergence zone that’ll set up," Mass said. That's the band of rainy weather that forms when the air flow splits around the Olympic Mountains, normally somewhere between Seattle and Lynnwood or Everett.
"So it’ll be particularly heavy there," Mass said, “[with] lots of showers in the mountains, especially on the western side. So Sunday, you know, so-so."
Sunnier And Warmer Next Week
But don’t despair. Mass predicts a change early next week, with things drying out a bit on Monday.
Then "a humongous ridge" will start to develop on Tuesday over the eastern Pacific, which will cause the temperatures to steadily warm for several days.
"And, in fact, it is quite possible, the temperatures could get into the lower 70s here in the western lowlands, as we get into Wednesday and Thursday," he said.
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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.
