A Week of Cold Wind Ahead! Plus Cold Nights

6:30pm Monday…

The bright sunshine today was nice wasn’t it?  It always raises my mood this time of year.  In December we “hit bottom” west of the Cascades with respect to the cold season.  It’s our darkest, cloudiest, and typically our coldest month of the year

Of course that is the average.  In some years January is colder (2017).   

Right on cue a very long period of cold east wind has begun this evening.  Why?  A split flow in the jet stream sends a wet system into California this week, keeping us all dry.  There will be no weather systems moving through the Pacific Northwest through at least Friday. 

We have long winter nights this time of year.  The airmass east of the Cascades in the lower elevations loses more heat than it gains during the day; not enough daytime sunshine to overcome the overnight cooling.  The result is strong high pressure centered east of the Cascades through at least next Monday!

There is only one sea level gap through the Cascades and that’s the Columbia River Gorge.  The cool airmass is less than 4,000′ thick so this will be what we call a GAP WIND.  Air will be flowing through this gap.  We don’t get air flowing up and over the mountains in this case (a downslope wind), so only those near the mouth of the Gorge will feel the wind.  That’s the central/east Portland metro area and hills around town too.

Right now the wind is just getting started with gusts around 60 mph at Vista House and 50 in Corbett.  Easterly breezes have begun to show up in the West Hills and east metro too.  Pressure gradients are up to around 4 millibars from The Dalles to Portland.    Models push it to 8 millibars by Tuesday morning and keep it in that general range all the way through next Monday!  This is going to be a long episode of cold wind blasting through the west end of the Gorge as the cold pool deepens east of the mountains. 

Peak gusts will reach 35-50 mph east metro, 60-70 mph western Gorge, and of course 100+ on the Vista House steps either starting tomorrow or Wednesday.

The dry air coming in from the east will minimize morning fog in the metro area tomorrow.  Then eliminate it the rest of the week.  Spots that go calm the next 3-4 nights will be COLD. 

  • Windy areas will likely not drop below 32 all week.
  • Calm areas will be down in the 20-25 degree range each night
  • The coldest outlying areas (Vernonia, Yacolt, etc…) could drop down into the upper teens.

That brings up an interesting point.  This pattern COULD produce the coldest temperature of the winter.  5 of the past 9 winters the coldest temp was in either November or December.  Of course we never know until we get to late February.

Try to stay warm this week and stay out of the wind if you can.

Chief Meteorologist Mark Nelsen

37 Responses to A Week of Cold Wind Ahead! Plus Cold Nights

  1. tim says:

    GOES 17 non operational until january 2019 now instead of dec 10th another setback .

  2. Die Fleas Die!, bring on the cold weather death to those vermin called fleas.

    On the more pleasant side, nice to see some sun. Been learning how to fly my Drone…unfortunately, it is not HD as described on the box but hey, that is what modding is for right? and as large as this drone is, I could probably fit my small JVC camcorder on the thing, or…grab an old cell phone that I have and get a gimble and use the cells phones “remote viewer option” and get some video that way.

    I hope to get some cool drone footage… now only if we can get a snow storm.

  3. alohabb says:

    The low temps have not planned out.

  4. K says:

    Alright, I’m quite pessimistic about the weather but next week into the week after looks (as of now) at the very least decently wet, if not quite stormy. Keep a lookout, as this isn’t a weak 50 mph jet over us at this point like last week and the week before (but rather models are forecasting a howling 200 mph jet stream right over us).

    • Ken in Wood Village says:

      What I did find interesting about the 12Z Euro was on Tuesday the 11th and on the 13th it had wind gusts over 50+ mph. There was another run (I think 2 runs ago) were it showed those gusts too. I know a week away but just wanted to point it out.

  5. Ken in Wood Village says:

    I went up to Crown Point today even though the winds were not as strong as I like them to be but I was a little impressed on how they were able to move me around. I think because it’s a “cold air mass” (which cold air is heavier and more dense) it was able to move me more than warmer air. I didn’t fall but I had to stand my ground really good to keep up. I will admit, after about 30 minutes, I was getting cold and needed to go back into my warm SUV…lol. Next time I will have my boots on with two pairs of socks and bring my heavier gloves…lol.

  6. Paul D says:

    I see the lows in the 20’s have completely disappeared from the 7-day forecast.

  7. W7ENK says:

    Unrelenting wind in downtown today, the trees outside my office were swaying non-stop. Took a lunchtime walk around the river, and despite the bright sunshine, the wind was cold on the hands and face!

    On that note, here’s a handy little graph that could come in useful for some this week. I’m not entirely sure, but I think this might be referred to as the Garbujita Scale? When I got home this afternoon, one of my three cans had the lid flipped open, and one was knocked onto its back, evidence of some “yellow force” wind gusts. The other one and the glass bin were just fine tho, so no worries, damage was kept to a minimum. 😂🤣😂

  8. Ken in Wood Village says:

    I see some eye candy in the 12Z GFS run. I also see another eye candy in the 00Z Euro too. At this point, it’s just eye candy..lol 🙂

  9. W7ENK says:

    If this turns out to be the coldest weather of the entire Winter season, then I’d say we are getting royally screwed over this year. Though, I didn’t really expect any different, so…

    • Roland Derksen says:

      23f here this morning. I was having the same thoughts- I’m HOPING this isn’t it for the season, but with El nino and the blob present, we’ll see…

  10. A crystal-clear, frosty 29˚F here this morning.

  11. Garrison says:

    Low of 25F in Aumsville

  12. Joshua Lake Oswego says:

    The temperature at my place has dropped less than a degree in the last 10 hours. Holding at 39. Nowhere near freezing.

  13. Jake in Gresham says:

    Early morning everyone. Man I was really hoping and thought I saw the end of this split flow for a day or two there last week. But this is boring weather no way around it. Weather station reporting:

    41 degrees and wind 9mph | gust 11. So the winds are for sure here.

    In other news, in Alaska the ice is way off from reaching the Bering Strait:

    Source: https://www.opc.ncep.noaa.gov/AK_tab.shtml

  14. Diana F. says:

    Somebody wake me up if it ever looks like it’s gonna snow, k? Cuz I am bored to sleep with this lack of weather, if ya know what I mean. The wind IS blowing pretty hard here right now, 2:18 AM Tuesday morning, but STILL! Come ON! Ice, Snow, Something? A huge rainstorm even!

    I’m up wrapping Christmas presents…shhh…..big ears on a 10 year old……..which I do every year in the middle of the night, several nights during December, and some years are FULL of awesome MON weather, but this year, OMG. We might as well be living in a California town where it’s 72 degrees year round! No thank you! I grew up in that!

    It’s years like this that I threaten to uproot and move to Buffalo or somewhere similar, ideally near water AND winter weather so maybe Michigan or Chicago? I dunno, I just want some dang winter weather and I don’t see it here, and I don’t see it on its way either!

    • Roland Derksen says:

      We might possibly see either mixed rain/snow or even some freezing rain here in BC on Saturday, but even that chance is small.

  15. Ken,when this cold starts to back can west snow?

  16. Ken in Wood Village says:

    Thank you for the update Mark. I will be heading to Crown Point tomorrow…hehe. 🙂

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