Cold & Snow Update: Sunday Morning

It’s time to prepare (if you haven’t already) for our coldest weather in 3-4 years; only about 2 days away now.  But if you want snow, that’s likely not going to happen at the lowest elevations.  At least in the next few days.


  • Very mild with light rain at times today.  South wind gusts 30-40 mph possible through this evening.  Rain will be heaviest from 5-10pm.
  • Ski areas have been washed out by rain, 2-3″ overnight!  Meadows and Timberline are just operating a beginner lift each…it’s pouring up there!
  • Light showers Monday…all rain, since sticking snow stays well above 1,500.
  • Showers end soon after sunset Monday.  Snow level at that point may be as low as 1,000-1,500′.  Those areas could get a dusting.
  • Dry from that point all the way until at least Friday.  This means no snow in the lowest elevations from Longview to Eugene is a very good bet.
  • Colder east wind arrives Tuesday morning as cold arctic air pours into the Pacific Northwest.
  • Coldest days Wednesday-Friday with highs near or slightly above freezing for the western lowlands of Oregon and Washington.  We haven’t seen that since a few days in November 2010 and during a cold spell in December 2009.  When the wind drops later in the week, we’ll see low temps well down into the teens, maybe even an 8, 9, or 10 in the coldest spots.  Our 7 Day forecast summarizes high temps and lows (in the city) well.
  • There are hints of some moisture returning this Friday or Saturday, if so, it would be cold enough for snow…all is not lost yet if you want some white stuff!

This graphic summarizes the snow (or no snow) situation well:


Details for the hardcore weather fans…

I was in Reno from Wednesday afternoon until late last night.  It’s interesting to come back and compare what I wrote 4.5 days ago with the maps right now.  Actually they aren’t much different!  I always see comments complaining about how the models are always flip-flopping and the GFS is horrible (partly true), but the big picture hasn’t changed at all.  A wet and warm system just ahead of a cold upper-level trough for Sunday, then cool showers Monday, then dry northerly flow Tuesday and beyond.  Sure, we’ve seen swings between just a “regular” cold spell and a huge arctic blast, but for the average Mr. Public,  they would barely notice the difference between a high of 25 and 35.  I did check in on models and maps off/on the past few days, and I did notice the ensembles of the models have often been colder than the operational runs.  I wonder if they have been misleading a bit?  Possibly, and I don’t know why.  But last night’s 00z ECMWF and this morning’s 12z GFS ensembles are a bit closer to the operation runs; by Wednesday afternoon only one or two ensemble members from each model shows anything colder than a -10 degrees at 850mb.  Finally a little better agreement:

tseries_850t_000-360_Portland tseries_850t_000-384_Portland

They predict a nice blast of cold and dry air, but not a huge event like 1998, or 1989, or 1990.  That said, it WILL be our first real hard freeze since Thanksgiving 2010.  That one lasted only 2 days or so.  So I’d say this will be more like December 2009.  The cold/dry air begins moving in Monday night and by daybreak Tuesday we’ll see dewpoints falling dramatically and a breezy east wind.  Right now the east wind doesn’t look too wild through mid-late week.  But I sure wouldn’t want to go up there to “experience the wind” now.  You thought a 45 degree wind was cold?  Try 25-30!

Now let’s talk snow.  There is an unfortunate disconnect between the onshore-flow showers Monday and the colder air coming down from the north.  A classic case of the moisture and cold air not lining up properly here in the lowlands of Western Oregon/Washington.  Snow levels through 4pm tomorrow are at best flirting with 1,500′.  Then soon after that time the dry northerly flow takes over.  If temps are still well up in the 30s to around 40 in the lowest elevations, that doesn’t do us much good.  Far more likely are wet areas freezing up tomorrow evening and lots of icy spots for the Tuesday morning commute.  I live at 1,000′ and think it’ll be real tough to get anything other than a dusting here.  You can see the WRF-GFS from the UW doesn’t even have hints of hilltop snow that we sometimes see in marginal situations:


But at least 6-10″ in the Cascades to push the sputtering ski season along.  This should be enough to get Meadows and Timberline to open another lift or two; although today’s rain sure isn’t helpful!

Too bad, it would be nice to get something out of this cold air.  There have been hints of a shortwave dropping down in the northerly flow and possibly spinning up some moisture for snow later this week.  This was the 00z ECMWF, showing some snow for Friday night & Saturday morning (the snowflake on our 7 Day forecast):


The 12z ECMWF is coming out right now and it shows (I waited 15 minutes for it to arrive in this spot)….well, well, well, still a little system for later Friday.  A colder shot of air behind it this weekend too!  Note the digging upper level heights coming down the Canadian coast:


Then the surface map showing precipitation spreading over Western Oregon and the cold offshore flow…that’s a great setup for snow.


Then an even colder airmass right behind it on Saturday…brrr!


Great…now that I’m back I’ll be model riding too.

Enjoy the warm rain today, and get those hose bibs covered!

Chief Meteorologist Mark Nelsen





262 Responses to Cold & Snow Update: Sunday Morning

  1. Snowing, sticking, 33F, arctic front still to N.

  2. petecj says:

    Up in Bellevue for work and it’s 50% snow and 38º

  3. Jake-(Gresham) says:

    I don’t mean to sound like a child but as a senior in college… nothing… and I mean nothing would make me happier then to have that massive snowstorm smash through on Monday after I take my finals. It’d be the perfect start to winter break.

  4. David B. says:

    Arctic front is taking its sweet time, as it sometimes does. It *might* presently be edging into Bellingham after hitting Hope just before noon. KBLI is down to the mid-30s with a rain/snow mix, and the wind is just starting to pick up and shift to the NNE there. Friday Harbor is still calm and in the 40s. The forecast for it to hit Seattle in the afternoon today is definitely a bust.

    My guess is that it won’t be until after bedtime tonight and maybe sometime tomorrow before it gets here. Won’t be the first time the timing of such things is off by 6 to 12 hours.

  5. EY (Oak Grove) says:

    Rain/Snow just above Longview. Longview is sitting at 37 right now.

  6. Ryan says:

    NWS confident it will snow Friday, mainly towards Eugene but a dusting still in PDX. Then we get coldest temps yet, followed by a potential bigger system Sunday affecting the entire area. Basically confirms what Rob and others have been saying in the last few hours. What I don’t understand is how a low coming into Astoria would generate more snow in Eugene than PDX?

  7. WEATHERDAN says:

    At 4:00 PM Omak Washington has dropped to 29 dewpoint 13 with North winds at 28 with gusts to 40. Bellingham has dropped to 35. Something special is headed our way I believe.

  8. Rob - Southeast Portland says:

    Heck of an 18z GFS run eh? I normally would scoff at this and say “Nice outlier”, but don’t be so sure. The very real possibility exists unlike many other times.

    We have full and total model agreement through HR 144 on ALL models across the board. GEM/GFS/EURO are all showing the same 500mb pattern evolution with energy digging out of Yukon down into BC. It rides south just inland through BC where it digs slightly off the Washington Coast and allows for a short-over-water trajectory pattern to develop conducive for spinning up an area of low pressure and picking up moisture throwing it up over top of our modified arctic air mass. As this heads south a 2nd shot of arctic air follows it which was shown on all 12z runs. Even 00z/6z GFS and 00z EURO shows this last night. Solid Ensemble support too.

    Now, as far as the bitter arctic blast after day 7? Possible. GFS and EURO show a crazy cold wave moves out of the Arctic regions As the Polar Vortex moves down into NWT, then it wobbles southwest through AB into southern BC. This air mass is not your typical Arctic air mass even for the high Arctic areas. Model show 850mb temps down to a staggering -30c to -33c moves into southern AB/BC. Incredible. Thickness 490 – 484. This is a historic air mass. Now, why do I think we stand a chance at this 2nd major reload next weekend? The Block is shown to pinch off being undercut by the westerlies by HR 168, however the NCEP Discussion said they felt the Block would hold and they did not favor a progression pattern feeling it was premature.

    Also, I think we’re going to see models trend this way after HR 150 That cold wave over BC/AB is so dense and massive it sags into northern Washington and it may very well push south becoming hard for the westerlies to push back against it or stop it, especially if the Block holds longer as the expert are leaning towards. With this deep of arctic air entrenched over OR/WA and especially Gorge/Columbia Basin it is going to be very hard to root it out of here. Models are always too quick to remove arctic air, and this is going to be more extensive especially Gorge/Columbia Basin. Watch for 7 days tonight or tomorrow to trend colder.

    • snodaze says:

      Agree with all of this. — With one small issue keeping me from wiping that smile off my face (re: my lol post below) because of said solid model agreement thru 6-7 days… — But how many times has an arctic air mass been contained east of the Canadian Rockies? Almost always 😦 But my fingers are crossed for 4-5 more days… That type of setup can completely fall apart inside of 36 hours. – ‘model’ wise)

    • snodaze says:

      and well said too b.t.w

    • boydo3 N Albany says:

      The way I read the NCEP outlook, we get 6-10 days or so and the pattern begins to de-amplify. I’l be we get the big rains following the big cold. Give it a week and a half or so and we maybe starting to talk pineapples…………

    • snodaze says:

      That’s sort of “anti-wishcasting” though boydo :-)… Pineapples are equally rare opposed to a colder transition– (in mid December?

    • David B. says:

      @snodaze – Actually the “pineapple express” pattern happens much more frequently than the “arctic blast” one. And 6 to 10 days is *long* for an arctic blast pattern to last — not short. So I can’t see how boydo3 is engaging in inverse (or anti-) wishcasting.

    • snodaze says:

      Naa… It just seems like it because what goes up, must and will come down… It’s normal… just not “pineapple” normal… I know what you mean though bro… (been around a long, long time…) 🙂

      Pineapple transitions create widespread flooding. (which you know) — That hasn’t happened since 96 (but I don’t recall what the weather was like just prior?… I assume very low snow pack.)

    • boydo3 N Albany says:

      Pineapples…don’t necessarily mean wide spread flooding, just lots of warmish rain.

  9. snodaze says:

    lol… Mother nature’s glacier building will be in full swing around PDX hrs. 180-192ish… Interesting it’s almost the exact same days in December, ’08…

  10. W7ENK says:

    Temperature has dropped 6 degrees from 48 to 42 in the last hour or so. ALMOST made that 50 mark in the city, but not quite!

    Losing the sun. Now begins our downward spiral toward freezing…

    The roads all look completely dry from where I’m sitting. Ice shouldn’t be an issue for most.

  11. alohabb says:

    WOW…7 day forecast for KPTV showing colder and opps for snow!

  12. Traci-Gresham says:

    Can someone explain how the models show these runs 7-10 days out that are “epic”, and yet when the time comes, they don’t seem close at all? I don’t know how the models work, and can’t read them, so where do they pick up that from, and how is it so off?

    As for today, when should the cold front get to us?


    • W7ENK says:

      That’s called “hype”. A few people do it, many more buy into it, and it becomes self perpetuating.

      The rest of us just sit back and laugh. But, if you are aware of this phenomenon and use it as a filter to see the reality of these crazy “epic” runs out at 7-10+ days, I’ve learned it’s best to keep your mouth shut, lest you be labeled a “Debbie Downer” or pessimist.

      Reality always comes to fruition. The hype and hysteria will subside come spring, but between now and April, it’s going to be like this almost continuously. Try to hang on and enjoy the ride!

    • W7ENK says:

      To answer your second question, the arctic boundary has pushed across the Canadian border into Northern Washington, into Bellingham on the Westside and Moses Lake on the Eastside.

      Marching Southward, it should be here to PDX by morning I should think.

    • David B. says:

      It’s typically just a few runs. Not worth getting excited over until the preponderance of model runs all start pulling that way. The one thing that may well be “epic” is the simple duration of the event; looks like it will still be going next weekend.

    • GTS1K' says:

      “I’ve learned it’s best to keep your mouth shut, lest you be labeled a “Debbie Downer” or pessimist.”

      When did this epiphany occur? 🙂

  13. Traci-Gresham says:

    What’s the verdict???? Will we see any snow tonight, or will the moisture be gone? And when is the next threat, thurs., fri. ?

    • W7ENK says:

      No moisture. Wait until Friday (at the earliest).

    • Traci-Gresham says:

      Well that sucks….to put it mildly. Unless of course we make up for it this weekend!

    • W7ENK says:

      I may have to eat my words…

      There appears to be some enhancement along the arctic boundary as it pushes across the Canadian border into Northern Washington?? Let’s clear out and dry up these lingering clouds so we’ll drop below freezing by the time it gets here!

  14. EY (Oak Grove) says:

    Sticking snow down to approximately 1200 feet just east of Sandy.

  15. Kenny says:

    OH MY GOD!!!!!!!!!!!!!!!!! The new 18z GFS gives PDX a HUMONGOUS SNOWSTORM! Storms just keep arriving and aint stopping! 1.5 feet to 2 feet are not out of the question! Then after all that snow, it get’s VERY VERY VERY COLD! OMG!!!!!!!!!!!!!!!!

  16. Weather Lurker says:

    Whatever you do, don’t look at the 18z GFS.

    “If it seems too good to be true, it probably is.”

  17. paulbeugene says:

    18z GFS incredulofabulicious

  18. W7ENK says:

    Sunny with very light liquid precip in downtown.


  19. alohabb says:

    Nice little hail storm in PDX.

  20. vernonia1 says:

    here is the 26 rest area……………. @1,400ft…but nothing at the Quartz Creek Br 1,100ft

  21. Andrew (Beaverton, OR) says:

    Rain/Snow mix downtown from the top of the Fox Tower

  22. gidrons says:

    Looking at tripcheck, its snowing on 26 over the coast range

  23. Sean in Sherwood says:

    Anyone know what has happened to the KPTV Tower Temp Page? For about a week now its been blank

  24. David B. says:

    After some wet flurries overnight Bellingham is now up to 41 and calm. But Hope, BC (at the mouth of the Fraser Gorge) is -1C with screaming easterlies (was above freezing there this morning).

    So it’s starting.

  25. DELXV says:

    3 hour pressure rises 4mb/3hr over interior BC and big falls over Nevada. The modified Arctic air is on its way…

  26. Model Rider says:

    Rob must be sleeping. We can usually count on his analysis from 12z.

  27. Ron says:

    A little off topic but it’s important: For all of you that feed birds, esp. hummers, the Anna’s don’t migrate and once you start feeding them they depend on it. Your feeders will freeze up so bring them in at night and set them back out just before sunrise. Have a second feeder always thawed and ready to rotate out. If and when the sub freezing east winds start to blow, feeders will freeze up in a short time. These little feathered friends need to eat every 15 minutes or so or they will die. Bird baths are important too because local available water will freeze up. Keep your water thawed as much as possible. A small aquarium heater works to keep things thawed.

    • Longview 400 ft says:

      Thanks for the reminder! We have humming birds here and I have to remember to do the same, bring in the water feeders at night and put them back in the morning. I guess I will have check them every so often when the temp does not get above freezing. They have thick coats so they should be ok.

    • Lurkyloo says:

      Great post, Ron. Thanks for that info.

      Speaking of birds, why are there seagulls flying around my house? Odd …

    • Dottie says:

      I discovered “cozies” for hummingbird feeders at Backyard Birdshop which I use to keep the nectar unfrozen during the day. Basically they are a cloth pocket that attaches to the feeder with Velcro. The pockets are designed to hold 6-hour hand warmers sold in bulk at GI Joe’s type stores for use by hikers, skiers, etc.

    • W7ENK says:

      Great info! It’s these little things people tend to forget about, or not even think about in the first place. Thanks for the reminder!

  28. WEATHERDAN says:

    How is it that last night while everybody from channels 2,6,12 and the NWS were predicting 30,s at best for next weekend Rod Hill on KGW 8 was forecasting mid 40,s for highs. I notice this morning that Nick Allards morning forecast was in line with everybody else. Any ideas where Rod was getting those temps from. He has had a warm bias the last several days. What gives?

    • David B. says:

      I suspect InAccuWeather.

    • pappoose in scappoose says:

      Agreed. Really hasn’t been himself lately.

    • WEATHERDAN says:

      I suspect dear old Rod might not be with KGW much longer if he continues to be so far wrong. That would be a shame because he seems to be a really nice guy.

    • Chris s says:

      It seems to me that back when he was at Katu, he was always the super bullish one. Now it seems as though he has done a 180, not sure why? But he keeps up with the bad forecasting and he won’t be around at channel 8 much longer one would think.

    • W7ENK says:

      I think he finally learned his lesson last winter (or was it the winter before?) when he jumped the gun calling for a big snow that never materialized, then went and basically yelled at all his YouTube viewers for believing his erroneous forecast. Since then, seems the pendulum has swung the other direction, and he now shies away from any and all mention of snow. This time however, I think (HOPE!) he’s wrong again.

      If he keeps it up, KGW may not have to let him go, he might throw in the towel all on his own? That would be a shame, I really like the guy.

      We shall see…

    • David B. says:

      W7 – Odds are he’s wrong; he’s going against the model consensus. It’s as unscientific to claim a cold outlier is going to come true as it is to claim a warm one is; “inverse wishcasting” is still a form of wishcasting.

    • Andrew (Beaverton, OR) says:

      It looks like those temps have been brought down by 5-7 degrees now.

  29. WEATHERDAN says:

    This is from Steve Pierces facebook weather page.

    Northwest Weather Consultants
    November 30 near Salmon Creek, WA via mobile
    ** Much Colder Weather Beginning Monday Evening **

    Computer weather model guidance continues to advertise the coldest weather so far this fall to arrive Monday night and Tuesday morning across the entire Pacific Northwest. Snowfall levels will crash Monday night into Tuesday. Additional reinforcing cold air is possible later in the week along with moisture from yet another disturbance. The devil will be in the details as we get closer, but residents can prepare for much colder weather beginning Monday and lasting through the week. High temperatures in the Willamette Valley and SW Washington will struggle to get above freezing mid week with overnight lows in the teens and lower twenties.

  30. Kenny says:

    Score, score, score, score! The new models are showing a normal snowstorm for Friday and then a MONSTER SNOWSTORM for Sunday Night! Then snow stays as even colder arctic air settles in! Score, score, score, score!

    • Jethro (Molalla ~320') says:

      And exactly one week ago you said:

      Kenny says:
      November 25, 2013 at 12:21 pm

      The new 12z GFS, GEM and EURO runs all coming into agreement now for a massive snowstorm here in the Pacific Northwest. Everybody gets a few to several inches of snow as the arctic front heads south on Monday. This snow will then stick around as even colder frigid arctic air makes it’s way down, then a massive snowstorm is projected to hit the PNW. I am that close to buying a bigger snow shovel because my current one is too small.

    • JohnD says:

      Good stuff Kenny.
      Love your enthusiasm.
      You rock!
      We’ll be pulling for this!

    • Sifton says:

      LMAO Jethro!! Oh Kenny, Kenny, Kenny………….

  31. Andrew (Beaverton, OR) says:

    Radar looks dry off to the west of the metro area yet i am seeing multiple reports of rain/snow mix and fairly heavy in some areas. Is the radar having problems picking up the precip today?

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