Tomorrow’s Snow & Ice: Looking Better! Not as Snowy/Icy

11am Wednesday…

I’ve taken a look at all the overnight/morning maps and models.  Several things stick out:

  1. There is good agreement now that moisture doesn’t arrive until midday tomorrow (11am-1pm) in the metro area.
  2. Precipitation forecast is quite a bit lighter than what we were expecting 24 hours ago.
  3. I would hate to be a school administrator in this situation


I’ve gotta tell you, this system coming in tomorrow has a bit of a “bust” potential.  By that I mean there are several signs (as mentioned above and more below) pointing to a lower impact event for our metro area roads and there is also a decent chance some of us in the metro get very little snow OR freezing rain.  Don’t get me wrong, there should still be plenty of icy roads tomorrow and I think freezing rain could be a big issue by tomorrow evening for some areas, but not the “frozen hellish metro area” that I was thinking 24 hours ago.


WINTER STORM WATCH continues from the NWS.  A Watch means conditions are favorable for an event.  This could be converted to either a Winter Storm Warning or Winter Weather Advisory (not as big a deal) later today

Dry and turning extremely windy tonight and Thursday.  Peak gusts 70-80 mph in western Gorge by morning and 40-50 mph eastern metro plus west slopes of West Hills.  The rest of us see gusts 20-35 mph.

Snow arrives in metro area sometime between 11am-1pm.  It could immediately change to an ice pellet or freezing rain mix.

Metro Snow:  Nothing to a dusting far south & southeast metro to 1-3″ way out west of Hillsboro or close to the Gorge.  The rest of us should be in-between.  From Clark County to Longview…similar totals Trace to 3″.

Willamette Valley Snow:  Nothing to 1″ along I-5 Woodburn to Eugene.  A little more west valley, quite possibly no snow east of I-5 (Molalla/Silverton/Lebanon)

Gorge:  Snow arrives midday.  6-10″ possible central/east end, lighter west end.  Lots of freezing rain west end tomorrow evening through Friday AM.  Finally warming late Friday afternoon/evening

Coast Snow:  A little too warm for snow, although could be a brief dusting up around Astoria/Seaside midday…maybe

Metro Freezing Rain:  Regardless of the impact to roads (whether it’s warm enough or not), I think freezing rain will continue on the hills in the metro area and near/in the west end of the Gorge well into Thursday night. It might be just on trees and powerlines as temps hang right around or just below freezing, but that can shut down MAX and cause power outages


There are 3 big reasons I’ve pulled back on the forecast quite a bit:

  1. The “freezer door” is open for the next 24 hours (Columbia River Gorge transporting cold/dry air west of the Cascades), but the freezer dial isn’t set that cold.  I know, this blog posting appears to have just run right off the tracks and into a ravine…but hang on.  We’re starting with a warmer atmosphere than we’ve seen in past big events (January 2016, February 2014, December 2008)
  2.  Midday arrival means roads have a chance to warm up a few degrees.  With the strong wind blowing tonight, we’ll barely get down to freezing, then roads will warm to mainly above freezing by midday.  When the precipitation arrives, temperatures will fall back to around 30-32 for most of the metro area, but not much lower.   It’ll be “tough” to get roads to freeze again.  Sure, snow will accumulate on them.  But once we change to freezing rain, temperatures need to be 30 degrees or below to keep a road frozen.  Got it?  As a result I don’t think every single road will be frozen, like we saw back in early January this year and the February 2014 snow/ice events.  In fact it’s even POSSIBLE that many roads stay clear tomorrow afternoon away from the Gorge and in the central/south metro area
  3. Precipitation intensity is far lighter now on all models.  Lighter precipitation (either snow or freezing rain) means a bit less cooling of the atmosphere due to the dry air overhead.  Less accumulation on roads = fewer travel impacts  Check out the ECMWF total precipitation forecast through tomorrow evening at 10pm:


Wow…Less than 1/2″ precip.  That means even if all snow fell and it all sticks, at most you get 2-4″ in the metro area.  This is through 10pm as well.  The last 6 hours there’s no way it’ll be in the form of snow.  Then take a look at the ECMWF snow forecast:


Notice the WRF-GFS is very similar:


You see the light totals as well.  Your next question may be…why no snow on the east side of the valley and very little in Clark County?  That’s due to temperatures warming in the afternoon up around 2,000-3,000′.  Yes, the fabled warm tongue of air pushing north along the west slopes of the Cascades. Yep, it could be a total snow shutout if you live in Molalla/Oregon City/Silverton/Battle Ground.  It starts too late to stick much midday, but by that time it’s already warming overhead and you miss out on the snow!  Quite possible.

East wind will be very strong tomorrow and it appears it’ll continue through tomorrow night in the Gorge and east metro area. Check out the WRF-GFS for 4am Friday…that easterly flow will still be going near/in the Gorge


As a result I don’t expect a sudden warmup in the metro area until early Friday.  Luckily we aren’t starting out extremely cold so by the Friday morning commute it’s likely roads away from the West Hills and Gorge should be just fine.

I know it’s a long post so let’s wrap it up with a few questions…

  1. WILL SCHOOL GET CANCELLED TOMORROW?  Wow, that’s an extremely tough call.  If administrators don’t cancel and snow covers many roads and/or ice at 3pm that’s a problem.  If they DO cancel and most roads remain wet at 3pm…they don’t win either.  Sorry folks, no good answer on this one
  2. WILL THERE BE POWER OUTAGES TOMORROW EVENING/NIGHT?  Possibly in the hills and east metro area (especially east of I-205) with ice accumulating on trees/powerlines, definitely in the Gorge, but they all have generators out there!
  3. IS THERE A BIG FREEZE AHEAD?  No, this morning PDX dropped to 27 and it’ll only drop to around freezing or upper 20s in outlying areas tonight.

Chief Meteorologist Mark Nelsen







81 Responses to Tomorrow’s Snow & Ice: Looking Better! Not as Snowy/Icy

  1. Taylor says:

    Very strong east winds in Happy Valley right now. Currently 32 degrees. It hasn’t dropped much in the last few hours. The National Weather Service tweeted back to me saying they see a weak low pressure system that is developing on satellite that the weather models did not catch. What could that mean?

  2. umpire says:

    Mark, I agree with you that this storm will be much less severe. Just drove to Boise today, and there is no snow cover until nearly to Pendleton. Also, temps from Troutdale to nearly Pendleton ranged from 32 to 35. Lots of sunshine as well. No freezer until the Blue Mountains, with snow and temps in the teens. Baker City did get to -1 last night, according to folks as gas station.

  3. Lee Wilson says:

    well folks we final hit 30

  4. Lee Wilson says:

    still learning to fly this thing.
    Hey Mark would love to see you get a UAV and post some video.
    I hear the news media may start using them..

    • Lee Wilson says:

      This is a Sky Viper 2400 HD, with a camera mod.
      It has live Video feed of 720p.
      earlier units had sme issues and also could not fly in freezing temps.

      Just a word of caution UAVs are subject to the same things like Icing.
      so if you fly them in freezing weather just pay close attention and make your flights short.

      also be mindful to other aircraft in the air.
      this UAV has a range of 360 feet. Some military and other choppers in the area fly right at that altitude, I hear them coming, I drop it out of the sky.

  5. Lee Wilson says:

    Le5 it be known here in Castle Rock , Washington we have hit 32 at this posted time.

  6. Wendy-Silverlake, WA says:

    Well it won’t do anything now. Our school is closing at noon tomorrow.

    • Lee Wilson says:

      You guys have to to have hit at least a bit below 30 up there by now…brrrr…

    • Wendy-Silverlake, WA says:

      Lol, barely got above that today.

    • Lee Wilson says:

      it hit 37 in down town Longview , while taking west side the temp went down to 35 up on hitting Lexington, it hit 35, then coming up that hilly area between Lexington and castle rock it hit 35, when we got home it was back to 35.. then in the last few hours it was dropping. but in the last hour we fell fast. so far were holding at 32..

      My guess is tha they will keep the school open but for those in the hills will have an excised absence

    • angela says:

      I’m seeing Castle Rock has hit 28 now

    • Lee Wilson says:

      hmm weird, my thermometer says 30 …

  7. angela says:

    UPGRADE!!! I hope Castle Rock schools add to the growing list of late starts and closings now. White wishes to all!!

  8. Lee Wilson says:

    Clouds finally covered what sun we had.
    Temp is now 34.
    I swear were dropping 1 degree per 2 minutes

  9. Lee Wilson says:

    Here is to hoping.

  10. Dave_in_Troutdale says:

    Possible bust. It’s getting tougher and tougher these days to combat global climate change ya mostly valley people. You could always move a few miles into the gorge, say Corbett, and enjoy the wintry mess that is about to take place. Stop whining and move.

  11. Lee Wilson says:

    Were at 35°F
    93 percent humidity
    Winds Swallocks 3 mph…

    In coming clouds from the west
    Currently the ground is really freezing.
    Snoopy had an ice ball in his hat…and he had to much eggnog.
    We never did thaw here.

  12. Alohabb says:

    Kids school in Portland already cancelled for tomorrow

  13. Brian Schmit says:

    Weather Group on facebook going crazy with almost 1200 people joined. Come join the fun on Facebook and learn about this current snow event.

  14. runrain says:

    I’ve concluded that weather is like a blind date. The anticipation is almost always greater than the reality…

    • Tyler Aldridge says:

      Does anyone else get the impression that Mark is being a little over cautious because of the wind storm that they predicted that never happened? This blog is all over the place!

  15. muxpux (Longview) says:

    So just enough to make things a mess. But not enough to stay home from work. I leave around 1:30pm and commute from castle rock to woodland. I don’t wanna be “hey it’ll be fine” make it to work and it never clears up then I’m stuck here. Probably just play it safe and call in anyway

  16. Lee Wilson says:

    Just got this about 20 minutes ago.

  17. W7ENK says:


    144 PM PST WED DEC 7 2016

    • runrain says:

      This is fascinating. What are they seeing that “we” aren’t seeing? How dare they challenge Mark! Still, to issue the warning they must be feeling more confident about the stronger storm scenario.

    • Sudnadja says:

      The NWS tweet announcing the upgrade also announced that the forecast was largely unchanged since this morning. I suspect that means a weak system but high confidence that it will happen, right?

    • Ryan (Walnut Grove) says:

      Just following protocol to assure the storm busts.

    • Lee Wilson says:

      Yup..bust that storm…it’s weak and pathetic…gives us snow 50 MPH winds…now that’s a storm…mother nature is getting weak with her winter storms…
      I remember a time of 3 feet of snow in the hills and 1 to 2 feet in the valleys. .and tobagoning down out hill..we used…Pam non stick spray…weeeeeee….that was fun….they we tried our to bogins to a saddle horn of a horse and yahooo…we kids had a blast…

      Ok, had to get that out..

    • HAWKEYES23 says:

      Ya they used to get a lot more snow back in 1648, that year killed off a lot of the magical unicorns as well.

    • Diana F. says:

      That’s so weird–when I went to the same site, it still had the watch up and no updates since about 11!

    • Sapo says:

      Runrain, it looks like NWS is almost exactly following models (GFS/NAM/WRF/ECMWF) snowfall maps as the average is about 2-5″ on the latest runs. Mark seems a little more cautious, and for good reason, because there’s some bust potential and qpf is lower.

      Just a guess, but I’ll venture to say we get widespread 1-4″, with higher accumulations westside and light ice accumulations. We’ll see though, it’s almost GOLU time

    • runrain says:

      Yeah, I’m a GOLU person. I just don’t have the technical know how of a lot of folks on here. I’ve GOLU’ed for many a year in these parts, though, so I’ve got that going for me!

      Thanks for the insight on the NWS, Sapo.

    • Lee Wilson says:

      Eh that three feet was back in 80 something.

  18. Lee Wilson says:

    Well, I will still be getting fuel for the generator lol. Just to on the safe side.

  19. GTS1K' says:

    Perhaps with the judicious use of an illudium Q-36 explosive space modulator we can turn things in our favor…

    …mine’s in the shop.

  20. Bianca Neve says:

    Can we cancel work for the next two days? Mark?

  21. WEATHERDAN says:

    28 here this morning. First frost in 262 days. A new record. 25 of the last 26 days have had at least a trace of rain. Weather certainly not boring this Winter. Merry Christmas and Peace to all.

  22. Joshua Downtown PDX says:

    The NWS is much more bullish than Mark. No changeover from frozen precipitation until tomorrow evening and 2-5″ of snow for PDX. I wish Mark wasn’t always right. Haha

  23. Windsday says:

    If we didn’t have a rapidly warming planet (I won’t debate the causes as there are many) we would be looking at a moderate snow/ice event back then known as a silver thaw.

    Eventually (sooner then later) match the 1,000 AD levels of warmth which didn’t happen exactly 1,000 AD. It was a 200 year cycle of ups and downs. Mostly up.

    We are seeing the beginning signs of it and likely have 200 years of it.

    That doesn’t mean it won’t ever get cold but the chances will be lowered as we reach the peak then it will slowly reverse assuming we don’t have anything that interferes with our planet’s orbit which I doubt.

    There are lots of active underwater volcano’s that continuously spew small amounts of lava and we are still in the ‘dark’ ages of having a real grasp of undersea knowledge.

    JK: Dammit! Where are our alpha sea bases we were promised as kids to live and study?!

  24. WWM says:

    oh myyyyyyyyy, why am I not surprised? laaaaaaaaaaaaame

    bust city USA

  25. John Fairplay says:

    You know, Mark, most of the time you seem like a pretty forthright forecaster, but this blog post is pretty bad. Seriously, you didn’t know yesterday that the atmosphere was “warmer…than we’ve seen in past big events”? How much did it warm up since 5:00 last evening and given all the temperature sensors available, how could you ever be surprised?

    In instances like this, I’d encourage you to stop posting snow and/or ice storms so long in advance of their actual possible arrival. If you had waited until today and it was still as significant as you thought it was yesterday, everyone would still have had plenty of time to get prepared and you could avoid being so incredibly wrong.

    • HAWKEYES23 says:

      WOW!!!!!!!!!!!!! Sour grapes man. Dont get your little dick in the dirt if you dont get a 2hr late start to school or work. I bet any info you could have provided would not of had any different type of outcome. If your that upset maybe start your own blog and get the fuck out of this one captain weather star.

    • runrain says:

      This blog is a forum for discussing possibilities, not the official stuff that’s broadcast widely. That’s why I always like Rob’s thoughts. Yeah, must times they don’t come to fruition. But the possibilities are always out there. In fact, for me, I almost find the buildup to be as rewarding as the outcome!

    • Washougal1100ft says:

      You act like it’s marks fault for weather maps changing like he has the power to change weather! Last I checked its his job to inform the public and the weather blog on what the maps show today! If you want more weather action move up a 1,000 feet in elevation and you will be surprised the difference. That’s what I did and we have had snow since Monday about 3″ still on the ground. You never know models could change still 24hrs time to do things either way it is what is dont wine to mark because your disappointed with the outcome!

    • HAWKEYES23 says:

      We will get some amount of snow, how much well I guess we will know in 30 hrs or so, no need to be a prick!

    • Jack says:

      Please disregard everything in the parent comment.

      Many of us appreciate the longdated analysis and predictions. And we understand your thoughts, analyses, and forecasts can significantly change, even hour to hour, as data and models are updated/revised. The experts I trust the least are those with certitude. Nothing is certain.

  26. Patrick Gump says:

    Let’s just hope there is enough snow to keep me home tomorrow!

  27. Diana F. says:

    Son a a Nutcracker!

    Well, at least there’s some wind to watch right now. It went from what I thought was the proverbial “calm before the storm”, to some great big, gusting winds. The neighbor’s flag tells me they are coming from the East!

    Pretty much accustomed to finding myself completely and utterly disappointed pretty much every single time there’s supposed to be a big snowstorm in PDX. Since WAY back when, it seems all the really fun stuff surprises us!

    Well… least I know I’m not alone~!

    (And the forecast prompted me to schedule a chimney sweep! Or, I should say, TRY to schedule a chimney sweep. It’s apparently the busy season & 1st available is 12/15.

    So…here we sit with a new heat pump that decided it’s leaving town for the month of December. I am currently wearing 3 shirts, 2 pairs of pants, and a fleece pullover. Oh and sheepskin Boot slippers. IN THE HOUSE where the thermostat reads 54.

    And I STILL want cold storms!!


  28. W7ENK says:


    Oh man…

  29. Max in Fairview says:

    “I would hate to be a school administrator in this situation”

    Yeah, I have a feeling they are screwed no matter what with this. Just a slight change in the Low placement can make all the difference. At this point, it may be better to look at the satellite loops, try to track the Low and compare to the models for placement.

  30. marinersfan85 says:

    Remember when I said yesterday that there wasn’t enough cold air on the east side and a few of you got insanely sensitive? I do.

  31. washougal1100ft says:

    flip, flop, flip, flop one more flip tonight and we should be good to go.

  32. No Snow says:

    Well hello there. Time for my yearly check in. The models have spoken and Mark concurs. No snow will be sticking downtown Portland. Bust-O-Rama 🙂

  33. Jesse-East Vancouver says:

    Better would be more snow, not less!

  34. We want snow to cover ALL THE THINGS

  35. Paul D says:

    Snowpocalypse has been canceled. Please resume your normal duties.

  36. Lurkyloo says:


  37. Roland Derksen says:

    19.2 F for a low here this morning. That’s my lowest temperature since Nov.30, 2014. The snow is predicted to arrive here late in the afternoon or early evening, but once it starts, it could stay as snow through Friday.

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