A Crazy Weather Night

Apparently we’ll need to get used to this in a La Nina winter?

Just as the heaviest rain seemd to be backing off, the snow level began dropping, as expected.  But then it just kept dropping on the east side of town up against the Cascade Foothills.  There is now snow on the ground well below 1.000′ in those areas.  Yet above 1,500′ in the Coast Range there is nothing.  Clearly cold air damming up against the west slopes of the Cascades.  I remember it happening in November 2003, and Halloween 1994.  That was the night several inches were dumped on Sandy, lots of trees fell on Highway 26, and a few power outages too.

I made a big change to the 7 Day forecast…a bit gutsy (we’ll see if it was a dumb move or model riding).

I feel there is a significant trend now in the “shorter range” of 3.5-5 days out, instead of 7-9 days out.  When it’s that close and models are getting into line (in this case pointing to warmer), I want to change the forecast instead of waiting for “just one more run”.  I had the snow/rain mix for Monday in there all the way until 9pm, then pulled the plug after seeing the 00z GFS and 00z ECMWF come in with almost exactly the same result.  The shortwave that was forecast to dig down right over us Monday/Tuesday (depending on the model) instead heads much farther east.  That does two things:  keeps us dry after Saturday, and takes the main cold air east.  So now can I reinstate that #2 and #3 from two posts back?  That’s not waffling is it?

There is also a hint of low level onshore flow returning Tuesday/Wednesday.  Both the ECMWF and GFS show moisture returning with the onshore flow…a bit strange, but I though we had something like that during Christmas Break two years ago.  The pattern looked familiar to me.

Okay, it’s midnight and I’m headed home to measure the snow.

* A side note:  Today was the most active day on this blog since the beginning of the big blast last December…27,000 views today! The year to year numbers are up a good 30%.


Chief Meteorologist Mark Nelsen

462 Responses to A Crazy Weather Night

  1. Kyle says:

    Forty one point zero outside and light rain.

    *Please snow come to Silverton* *Please snow come to Silverton* *Please snow come to Silverton*

    *Please snow come to Silverton* *Please snow come to Silverton*

    Ummmmm where was I?

  2. Kyle says:

    AHEM! Does anyone know WHEN the low will move in as in my last unanswered question?…………………ehh never mind I’ll just be surprised like the good old fashioned way. 🙂

    Thanks for the support.

  3. Kirk (Sandpoint Idaho) says:

    Emily – they must live close to Smith Lake! I was just there fishing with my kids.

    sds – yep that’s me I used to be Camas Moms neighbor. Hell ya I’m going to get snow!

  4. goducks09 says:

    I keep on looking at the IR loop, and to me it looks like the low off the coast is still moving southeast, and not completely east…
    Is it supposed to make landfall on the WA or OR coast?

    • Rob "Wrath" S.E. Portland says:

      It is moving ESE, but likely turning due east soon. It is about due west of Tillamook. This low is supposed to approach the Coast hanging just off Astoria. Some models have it turning northeast into SW Washington too. If it were to say remain south off Tillamook that could allow some light Gorge wind to filter west….

  5. PaulB/Eugene says:

    Model Roundup:

    UKMET: Quick arctic blast: 528 dm heights at 96h
    Canadian: Quick arctic blast: 534 dm heights at 96h
    GFS: Quick arctic blast: 532 dm heights at 96h
    NOGAPS: Arctic air mostly east of Cascades: 544 dm heights at 96h
    ECMWF: Arctic air mostly east of Rockies: 542 dm heights at 96h
    JMA (12Z): Quick arctic blast: 537dm heights at 96h

    00Z GFS ensembles good.

    00Z Canadian ensemble mean 500mb height at 96h: 540dm…borderline between arctic blast and arctic air missing us to the E.

    Best chances for snow N of Seattle, E Oly Peninsula this weekend. Likely will see some flurries here early next week but doubt anything more than 1/2 inch on the valley floor. Even inside of 96 hours, not certain yet of what will happen.

    • Rob "Wrath" S.E. Portland says:

      Thanks as usual for your model breakdown and analysis.

      6z NAM in 1 hour
      6z GFS in 2 1/2!

    • PaulB/Eugene says:

      Interesting to note that GFS Ensemble mean for 500mb heights was at or lower than operational run at PDX @ 96h (I think it was about 528-530)

    • Rob "Wrath" S.E. Portland says:

      Any thoughts on why models are so confused 2 days out? GFS/NAM in agreement, Canadian is close, but EURO slides cold air furthest east. I base things on those 3 main models. Is it simply the handling of the PV as it moves down out of the Canadian Arctic?

  6. Cherie in Vernonia says:

    slush…snow pack breaking up Wilson Rvr Summit Hwy 6

  7. BrandonInNWSuburbia says:

    A friend of mine just said it’s snowing at her place in Banks.

  8. timmy - scappoose says:

    Rob, Im guessing you havent been looking because you would have posted it. KPTV towe temps as of 9pm
    trending down fast.
    T1 1.0c
    T2 .5c
    T3 .5c

    last night at midnight they ranged from 2.3 – 3.1c

  9. Rob "Wrath" S.E. Portland says:


  10. Anthony Bertolo - Gresham 500' says:

    You know, looking at the latest GFS, we could very well see some snow down to 500′ Saturday evening.

  11. Danny in Troutdale says:

    Bruce from Koin says “Saturday morning: Our forecasting tools are trying to give us snow showers in parts of the metro area; but, there’s a question about how much moisture is around. Saturday morning lows are likely near freezing.”

    hmmmm…..I dont think he means the lowest elevations like where I am 😦

  12. New 7 day up. Temps bumped down a bit Monday and Tuesday.

  13. Rob "Wrath" S.E. Portland says:

    00Z EURO is again worlds different than the GFS/NAM/CANADIAN. Not nearly as cold….

  14. jackfrost says:

    How bout the Blazers fighting back and getting the W without Roy!!!

  15. Pippin says:

    Sloppy snow coming down over the sylvan hill on 26.

  16. Kirk (Sandpoint Idaho) says:

    Snowjunkie – Hayden\CDA is 45 miles south of us with about the same elevation. So the weather is very similar. Locals say Sandpoint usually gets a bit more snow, but not a lot more. Summers are amazing with a ton more sunny days than Portland. We love it here. I hope you will too.

    • Emily Waldman says:

      My inlaws live in Bonners Ferry north of town up the hill off US 95 just past the three mile intersection, where there’s a restaurant & store. The drive is beautiful in the fall in the sunshine. They do get snow, below zero temps & stock up on long johns, as you will need then. The skiing is the bomb! I grew up in Spokane. Enjoy!

    • sds says:


      Are you the same Kirk that used to live up above “Camas Mom” ? You are going to get SNOW.

  17. Currently 37.2°F and raining. . . Went for a walk a couple hours ago (between showers) – it was brisk but beautiful. . . Can’t wait to see what happens early next week. . .

  18. I’ve picked up 6.02 inches of rain this month so far…that’s pretty crazy! And since February 38.88 inches of rain has fallen out here.

  19. Kirk (Sandpoint Idaho) says:

    Camas Mom-This morning we did. Snowed all day on and off but did not stick. Supposed to get 1-2 inches tonight. They are saying low temps below 0 next week.

  20. B1900 Pilot says:

    For those who may be lurking and need all of this weather lingo to be deciphered (example “I can’t wait till the 00Z GFS initializes!”) here’s a good website that explains all of this, especially in regards to snow down at the valley floor.

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