Expect a brief respite on Friday and intermittent breaks this weekend from the extremely wet weather that has doused the Puget Sound region all week.
KPLU weather expert Cliff Mass says a front is moving through and the lowlands will see showers but not extreme rain. It’s a different story in the mountains, however. Mass says there could be as much as six inches of new snow on Friday, continuing a trend that’s brought huge amounts of the white stuff to the passes and ski areas over the past several days.
Perfect Conditions For Mountain Snow
“Snoqualmie Pass has had a foot and a half of snow – it’s just extraordinary,” said Mass, who teaches atmospheric sciences at the University of Washington. “We have gone from about 70-80 percent of normal snowpack to over 100 percent right now, over most of the Washington Cascades. So we are not only normal, we are above normal when it comes to snow,” he said.
“And there’s only going to be more. It’s just a startling pattern.”
Mass says the key factor in bringing all this snow is the wet northwesterly flow that has been coming in from the Gulf of Alaska and combining with temperatures that are cold enough to deliver snow at pass levels.
“And we’re going to have that this week,” he said.
Lowland Showers And Sunbreaks This Weekend
Saturday he says there will be a break in the precipitation during the morning and early afternoon, but another system will come in Saturday night and into Sunday morning, again hitting the lowlands with rain and the mountains with snow.
As that moves through on Sunday, he says there will be another pattern of showers and sunbreaks, but it will stay pretty chilly. “Temperatures in the lowlands only getting up into the mid-40s,” he said. “So we’re not talking about warm.”
Mass says it could get pretty windy as well, with gusts in the lowlands reaching as much as 30-35 miles per hour Saturday night and maybe more in the mountains. But those systems aren’t strong enough to produce major windstorms.
Skiing Conditions Likely 'Best In Years' This Christmas
Next week, expect similar conditions to continue all the way to Thursday.
“I can’t believe what the models are showing,” Mass said. “Basically, this pattern stays in place all the way through Christmas Eve, with a series of systems coming through, cold temperatures and the mountains just will get feet of snow.”
So Mass says by the time Christmas day rolls around, there will be several feet of new snow, bringing snow pack levels to well above normal for this time of year. “And the skiing over this holiday period should be absolutely exceptional – probably the best in years.”
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.
