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Fog to blow out of Snoqualmie Valley soon; little rain, but relatively quiet weather until mid-December

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Visibility really dropped on Wednesday, December 4th, as the fog rolled in.  You can see why this happened (from the chart below) – as the day rolled on temperature and dew point nearly converged.
Wunderground weather station (KWASNOQU33) from Snoqualmie Ridge 
Fog can begin to form when the difference between air temperature and dew point is less than ~4° F.  Water vapor condenses into tiny liquid water droplets that are suspended in the air. I was driving through downtwon Snoqualmie last night and the sky looked eerily red and gray, like something out of Stranger Things. I gathered it was due to reflection off water vapor from the mix of Christmas lights in the surrounding area, as well as the field lights that were on at Mount Si High School.   The fog also made for some really cool Christmas light reflections in my neck of the woods.

As for the rest of the week, another pressure gradient should form over the Cascades bringing back our beloved Snoqualmie Valley gap winds – probably begi…

Cascade Gap winds kick up Saturday night, light snow possible Sunday

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Windy Saturday into Sunday... Higher confidence that a Low will move into proximity off the coast Saturday setting up an East-to-West pressure gradient that should kick up howling Cascade gap winds later Saturday into Sunday morning, at the peak of it probably gusting 40-50 mph at times in the Snoqualmie/North Bend vicinity.  
Wind Gust map for W. WA overnight 11/30/19
Possible light snow Sunday, but more likely to just remain dry vs. Puget Sound…Incoming moisture from the southwest over the cold air already in place is often a recipe for snow, however Western Washington is only expected to get grazed with precipitation Sunday, with the brunt remaining offshore of the Oregon coast.  Southwest WA, parts of Kitsap County and even the I-5 corridor (including Seattle) may see brief accumulations before turning to rain.  Out here, we’re higher in elevation and we generally get more precipitation, so better chance for us to see the white stuff, right?  Not likely this time around.  I’d estimat…

Snoqualmie Pass finally gets some needed snow; colder Thanksgiving temps on way for Snoqualmie Valley

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Snoqualmie Pass was finally getting some much needed snow Sunday night into Monday morning, November 24th.  The mountain passes are expected to receive  6-12” through Tuesday. The foothills are on the fringe for possible snow later Monday into Tuesday morning, but odds have diminished. The atmosphere will be drying out fast as the cold air moves in from the north, but if a typical north puget sound convergence zone setup shifts southeast, it’s possible to see a trace-2” in the foothills of Snoqualmie and North Bend – though this is looking less likely with almost every model run the past few days.  The Euro model’s mean ensemble run shows maybe flurries/dusting overnight Monday into Tuesday while GFS now calling for completely dry by the time cold enough air arrives.  

University of Washington WRF-GFS 4km resolution forecast. Right scale showing 24-hr snow accumulation (in inches) as of 4pm Tuesday We’re transitioning to a flow from the north, ushering in modified arctic air into Western…

Nov 5th marks earliest in season for 1"+ of snowfall at Snoqualmie Falls

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This day in 2017 (Nov 5) Snoqualmie Ridge received 2-3" of snow.

Couger Mtn-Bellevue 4-6" dumping.

In fact this date marks the earliest in the season ever for accumulated snowfall (1.0") recorded at the official NWS Coop Snoqualmie Falls weather station (looking at records back to 1945)
Fast forward to our current 11-day dry spell☀️.. aside from some minor gap winds that should kick up tomorrow night, rain chances keep getting pushed back. Latest model runs showing maybe a light shower this weekend, with chances for any significant precip more likely early next week.

Largest October flood event on record

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So how did today's Snoqualmie river flow end up ranking historically?

Today's peak flow, measured in cubic feet per second (cfs), near Snoqualmie Falls ranked 14th all-time (based on historical NWS data back to 1959)



The only earlier in season I could find over the threshold of what's considered a 'major' category flood (~41,000 cfs), ranking in at #20 was 10/16/1988 at 40,400 cfs
Also notable, 2015 had three independent flooding events!  Only 1975 (2) had more than one in top 20.
Data: NWS