Some Fresh Snow On the Way…In the Mountains


Our very slow weather pattern continues through the next 7 days as high pressure dominates the eastern Pacific Ocean.  That means we don’t get any wet systems coming at us from the southwest or west.  But that does leave the door open for a “quick hit” as systems come down the back side of the ridge offshore.  Basically a weak system can come down out of British Columbia.

One of these will move through Thursday with a few sprinkles possible, or flurries in the mountains.  Then a stronger one drops in over us Friday night and Saturday morning.  It’s gone by Sunday as the ridge pushes closer to us, but it’ll bring a quick shot of showers in the lowlands and snow in the mountains.  Here’s a graphic showing what I expect (right now):


Notice that out of the next 7 days there is only a 24-48 hour period with any appreciable precipitation, and “WEEKEND” is probably a bit much…it’s really later Friday and the first half of Saturday.  Still, we’ve lost most of the snow below 5,000′, so this will get a base going again below those elevations.

You may also notice the lower snow levels?  This will likely be the first time this season we see at least a dusting down to 2,000′, maybe a little lower.  Models have been all over the place with moisture and amount of cool air moving in over the weekend.  The 12z/18z GFS would barely get snow down to 2,000′, while the 12z ECMWF is a little colder; thus the 1,500′ snow level on the graphic.  Just 24 hours ago models had the cool system much farther to the east as it moves south, keeping us mainly dry!  And that could change again in the next 24 hours.

What does this mean for the lowlands?  Not much, except high temps will be a little cooler starting Friday through early next week and it’ll be wet for parts of Friday and Saturday.  Expect highs only in the 40s for a few days (assuming current models are correct).  We’ve been near to a little above normal so far in November, so this will bring that average back down to normal or below.  We may see the gusty east wind return Monday-Tuesday.  If so, it’ll be a 10 degree cooler east wind compared to what we just saw Sunday and Monday.

In general the drier than normal weather will continue through the next week or so.  As you can see from the chart above, that means no fresh snow for the first half of next week.  So, as of now it looks like a long shot to get ski areas open for the weekend before Thanksgiving (Nov 23rd-24th).  Beyond that, the last week of the month is a big question mark though…we’ll see if the pattern turns wetter.  A lot can change in two weeks!

ed forman

By the way, three of the FOX12 weather folks will be on the ED FORMAN SHOW this evening.  Yes, the King of Late Night in PDX.  It’s a (very interesting) talk show in downtown Portland and we’re part of his NEWSvember.   Brian Macmillan, Joe Rainieri and I will be at Dantes (3rd and Burnside) around 9:30-10:00pm.  Should be fun!  You’re welcome to come on down too.

Chief Meteorologist Mark Nelsen

61 Responses to Some Fresh Snow On the Way…In the Mountains

  1. Rob - Southeast Portland says:

    00z GFS has trended towards the 12z GEM which followed the 18z. Ugly Ugly. I’m sure 00z EURO will too.


    • BoringOregon says:

      So does that mean. Some thing is going to happen or not!?!?

    • Benjamin (West Salem) says:

      “Ugly Ugly” makes it sound like no, nothing exciting… 😉 lol

    • boydo3 N Albany says:

      Yeah, longer range looks like inversion time. But the weekend drive by cold shot is still mostly intact. I’m thinking this is a bi-monthly pattern. Seems to be so far. But when we break out? Who knows…..

  2. JJ78259 says:

    Well Sifton we are going thru our first arctic blast here in San Antonio down to 36 tonight. Last night 34 but back to 82 and 85 Saturday and Sunday with lows in the high 50’s. Just a quick update!

  3. Dave in SW PDX (235') says:

    For those who have been asking for it, here’s the link to NOAA’s Model Guidance page:

    You’ll still have some work to do, though. First select the Model Area; I usually select North Pacific (NPAC). Then select the Model Type (GFS, NAM, etc.), and you’ll be directed to another page where you can select the Model Cycle (00Z, 06Z, 12Z, 18Z) and other parameters to view the latest model output. Have fun!

  4. Rob - Southeast Portland says:

    00z NAM
    528 thickness PDX…. but the trough isn’t digging south or southwest enough. Chilly

  5. Marcustheweathernut says:

    Does anyone have links to the Nam, gem and gfs models?? I seemed to have lost mine ..

  6. Rob - Southeast Portland says:

    00z NAM in 1 hour

    00z GFS in 3 hours

    00z GEM in 3 1/2 hours

    00z EURO in 6 hours 3 minutes

  7. BoringOregon says:

    ****Amazing sunset alert****

  8. Brandan says:

    All of the runs combined to create the ensembles.

  9. High Desert Mat says:

    Rob, what do u get from todays 12z euro and the 18z gfs. They seem like they have flipped again for the better from what I get from them. But it is 18z.

  10. stevied (North Portland) says:

    18z GFS is some eye candy in la la land…chilly temps.

  11. Marcustheweathernut says:

    12z euro looks a little cooler than last nights 00z run…. But nothing exciting yet!!!

  12. Jethro (Molalla ~320') says:

    Time to issue a cold rain warning for PDX this weekend… may need to issue a breeze watch as well for Friday night.

  13. Rob - Southeast Portland says:

    6z GFS Ensembles were a bit colder than the operational with some members -8c to -10c… But we’re losing agreement amongst the EURO/GEM. We’ll see what 12z runs show later this morning. Ya never know…

  14. Rob - Southeast Portland says:

    Unfortunately I bring bad news.
    Both 6z NAM/GFS look to be trending towards the GEM/EURO.


    • High Desert Mat says:

      Uh Rob, look again, 12z Euro is back. But it looks like a really quick hitter. Then on to a weak type of zonal flow.

  15. schmit44 says:

    11/12/2013 Oregon (All) Temperature Summary

    High:66 at Lorella(4160 ft)
    Low: 54 at LINCON Lincoln C(187 ft) & Gold Beach (US 1(60 ft) & CW8449 Charlesto(322 ft)

    High:41 at Rim(7050 ft)
    Low: 24 at RED BUTTE (4460 ft )

    Largest Diurnal Change: 37 degrees
    LAKEVIEW (65/28 ) (4770 ft )

    Heaviest Rainfall:
    1.32″ at RED MOUND(1753ft)
    1.05″ at QUAIL PRAIRIE LO(3183ft)
    0.93″ at BROOKINGS(79ft)
    0.81″ at Brookings Airpor(459ft)
    0.77″ at DW0237 Lees Camp(699ft)

  16. Marcustheweathernut says:

    00z ecmwf don’t look cold to me…..??

  17. Rob - Southeast Portland says:

    00z WRF alert!

    Now THIS is a strong east wind event. Very impressive modified arctic air into the Columbia Basin fueling a PDX-DLS gradient perhaps -10 to -12mb maybe as high as -13mb. 100mph+ at Crown Point likely(along the south facing stairs)

    • High Desert Mat says:

      That east to west gradient looks fierce. Hope that comes to fruition since I live where that cold air is coming from kind of. I’m in Redmond.

    • High Desert Mat says:

      Mark what do u think my highs and Los would be looking at this one graph? Please answer so I can get a good idea not coming from interns lol.

    • boydo3 N Albany says:

      Looks pretty frosty on the east side. Surface temps might get into the teens or lower depending on winds. With a bit of snow followed by clear nights…………..burrrrrr
      How’s your pipes?

    • Jake-(Gresham) says:

      Well hopefully this is the first real run of several and the model trend holds. I wouldn’t mind a strong east wind event even if it can be brutal at times.

    • BoringOregon says:

      No way really?!?

    • High Desert Mat says:

      Pipes on this side of mts. are good. Think they’re dug deeper in the ground. They never freeze unless its below 0.

  18. Marcustheweathernut says:

    This May be a stupid question…… I keep hearing the term * modified arctic air* what exactly does that mean???

    • Ben T says:

      From what I gather, it means that it is an arctic blast which is not as full-fledged. Like it would be cold but not bitterly cold and wouldn’t last as long, as a legitimate Arctic Blast would. Those more well read on this feel free to correct me.

    • Marcustheweathernut says:

      Ok cool thanks Ben

    • Benjamin (West Salem) says:

      I think modified arctic air is when we get more of a glancing blow, with the gorge as the only source of cold air. The bulk of the really cold air goes well east of us into Montana and the Dakotas. I think of Dec 1990 or Dec 1998 as a full arctic blasts and Dec 2005 as a modified arctic air mass.

    • SilentReader says:

      actually i believe all air that originates from the arctic (and northern regions near) are considered modified. the path the air takes to get to us causes the air to modify (warm). depending on its path it can modify more (over the ocean for example) or less if comes directly from the north or funneled in from the east. No matter how you slice it all arctic air is modified by the time it reaches us.

    • pappoose in scappoose says:

      I believe the same, SilentReader.
      (although I don’t think it’s referred to as such after a trip over the ocean)

  19. NAM cold enough that there could be some snow up here at 84 hrs.

  20. Muxpux (Castle Rock 175') says:

    Dante’s is much more fun on Sunday nights

  21. Sifton says:

    Dante’s huh?? Right on, I’ll buy the 1st round Mark!!

  22. Rob - Southeast Portland says:


    Thanks for the update, Mark. We’ll see if 00z is colder or if 18z was a trend towards a slightly warmer scenario. Either way as you point out it will be chilly, just how chilly is unknown as of yet.

  23. Been by Dante’s several times but never went in. Glad to see the chance of some mountain snow coming up too, thanks.

  24. BoringOregon says:


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