A mild January; but weather pattern change brings much drier weather soon

7:30pm Monday…

The weather pattern these past 3 weeks has been somewhat monotonous; lots of clouds, rain at times, and temperatures a bit warmer than average. The Christmas Weekend ice storm was the beginning of a long wet period; lots of (usually) weak weather systems bringing regular rainfall. The only dry day (without measurable rain) in Portland this month was New Year’s Day!


That gives us 15 consecutive “rainy days” in Portland as of this evening. I make the giant leap of faith that incoming showers will deposit at least .01″ rain at PDX before midnight of course. Which brings up the question…

What’s the longest consecutive rainy stretch in Portland weather records?

It’s 29 days; nope, not quite the biblical 40 day stretch, but close! You may be thinking we MUST have gone 40 days or more in the past. Most likely it’s been a situation with 20 days, then a dry day or two, then another 20 days. Here are the numbers; notice total rainfall at mid-month is about normal.

Wx Blog
Wx Blog(kptv)

In a typical year, we are wettest from late November through December, then (believe it or not), rain starts to back off a little bit in January and February. One of those 3 years sticks out. January 1950. Any serious local weather geeks knows about January 1950. Who would have thought that THE coldest, and THE snowiest month in Portland’s history would also contain the longest “rainy” stretch! 41″ of snow fell that month on 21 separate days! All the melted snow, freezing rain, and liquid rain added up to 10.10″ precipitation for the month…a soaker. BTW, the 2nd coldest month was the previous January…1949.


Quite a change is in store for the West Coast. The persistent westerly flow that brought flooding to California and consistent (lighter) rain to the Pacific Northwest will dry up later this week. The pattern change is a strong upper-level ridge of high pressure developing over or just west of the West Coast. This graphic shows 500 millibar height from the ECMWF model ensembles. Warm colors represent higher than average heights, cool colors lower than normal. This goes from now through the next 15 days.. Each image of the animation represents a 5 day average.


Higher heights mean more sinking motion in the atmosphere = drying and less cloud cover. The result is drier than normal weather beginning this Thursday and continuing for the following 7-10 days. From the Canadian model ensemble average…well below normal all along the West Coast over the next 10 days


Models are in agreement on this big change. See the ECMWF ensemble forecast for Salem rainfall. Not much happens from this Thursday all the way through Saturday the 28th (both circled below)


As of this moment, there’s no strong signal that the big ridge could back up and allow an arctic blast to flow south into the region. Remember we started with dry ridging in mid-December, then transitioned into the cold pattern for a week or so as that cold air came south. GFS temperatures are very stable for the next 10+ days. This IS the ensemble average, but I’m not seeing many members going REALLY cold next week.


Due to the ridge being slightly west of us, I don’t see a long (or significant) period of strong easterly Gorge wind. That’s good, because it has been a ROUGH season so far. At this moment, Troutdale has seen as many “gusty east wind days” as ALL of last November through February!


November and December combined saw more windy days in the east metro than any other November+December since 2006. Too much wind. We will see how many FOR SALE signs go up in Troutdale, Camas, Gresham, and Corbett this coming spring…Remember the wind peaked on December 23rd with a gust to 88 mph in Corbett, 93 mph beside Women’s Forum SP viewpoint, and who knows how strong at Vista House. Oregon State Parks folks tell me they will be replacing the anemometer that blew away that day, hopefully with something a bit stronger.


  • After a bit more rain later Tuesday and Wednesday, we’ll see far more dry than rainy days for at least a week or so.
  • Temperatures cool to near normal or slightly below the next 7-10 days, but nights will cool and frost becomes more common
  • There’s no sign of a long east wind period for at least the next week
  • There’s no sign of cold arctic air or lowland snow through early-mid next week…at least through the 25th
  • I don’t see windstorms or flooding in this weather pattern
  • Your life should remain relatively unaffected by weather for another 7-10 days

57 Responses to A mild January; but weather pattern change brings much drier weather soon

  1. Ken in Wood Village says:

    The GFS looks weird so ignore it. I think someone inputting some wrong numbers. The Euro and Canadian models are in good agreement showing colder temperatures next week. It’s still a long ways off but it’s looking more and more likely we will see colder temperatures. The big question is, will we get moisture with this cold weather? We won’t know until we get closer to the event. It’s a wait and see for now 🤗❄️

  2. There are very strong hints that ridging is going to back up very near a sweet spot by the end of next week. Spring? You’re gonna have to wait a few more weeks, and until then, suck it up buttercup. 😆

    • Ken in Wood Village says:

      I agree Mike. It also looks like there is a possibility of a snowstorm if the storm takes the right track. It’s still a long way out so the details are still not set yet.

      It’s just a waiting game for right now. 🙂

  3. Pgiorgio says:

    Models have trended drier and warmer.

  4. tim says:

    The 18z gfs has a mini blast at the end but it’s the 18zzzz so who cares. Anybody noticed the days are getting much longer now?, here comes spring!.

  5. lurkingsince’14 says:

    As others said feel like this mornings action was understated by the all the mets. Long periods of frozen precip and imagine it got pretty slick in the hills.

    Cool to see some winter weather again! 👏🏻

  6. Longview 400 ft says:

    Currently 34.5
    A few snow showers today along with sleet, graupel, and earlier this morning hail showers.
    What a fun day so far.

  7. Rick says:

    Snowing hard. I’ll bet it’s at least 2” per hour rate. I do see a back edge on radar so it will be short lived. Nice to see nonetheless, wasn’t even in the forecast.

  8. West Linn 200 says:

    Big flakes here, nothing sticking of course, but it’s cool to see. I don’t recall anything about this in the forecast yesterday.

  9. TSL says:

    Snowing in Gaston at about 300 feet. Nothing sticking though. It’s 35 degrees here.
    Thought there was a dry weekend in store, change of weather plans I see

  10. Ken in Wood Village says:

    Some models had shown the possibility of either snow or sleet for today’s storm coming in. As I can see from the comments, that’s coming true. I actually didn’t think it would happen but it got cold enough to happen. I was in Beaverton when it started happening, I’m back home and there is a little sleet mixed with snow. The heavier moisture isn’t here yet but I can see by the radar, that’s about to change 🤗❄️

  11. Charles says:

    Snowing at ~550’ in Cedar Mill. Pleasant surprise!

  12. lurkingsince’14 says:

    Hail/sleet coming down solid bridlemile area. Most interesting weather in a month!

  13. Rick says:

    Full blown sleet storm coming down. Don’t believe this was in the forecast for my area. Currently at 32 degrees with 1/2” of sleet on the ground. All white and looking good outside.

  14. Ken in Wood Village says:

    This is going to be a short post. As you can tell, the operational runs are showing a good turn for the best for cold air by the end of the month. The ensembles on both the Euro and GFS are trending downwards. I hope this will continue.

    • Andrew says:

      The EURO ensembles hadn’t been looking as promising on arrival of cold enough air. That has changed on recent runs. All models now indicate a pattern that can support lowland snow. Nice to see. As things stand today, it look like the week of Jan. 30 is when things might get interesting. The cold pattern also appears to stick around for a while, though I’ve noticed in recent years that it’s common for models to exaggerate this in the extended, as was the case in December when early runs showed cold continuing well into new year. It’s still very early to start forecasting trajectory of arctic air but it’s nice to see in some of the model runs i’ve seen that there may be multiple cold troughs that cycle through. I always like to see that since we all know the setup and timing has to be just right to get a snow event. When that cold stays proximate and keeps reinforcing itself, it only improves our chances of generating the other ingredients.

  15. Evan -- Cedar Mill says:

    6z GFS is an absolute beaut

  16. WEATHERDAN says:

    I will get roundly criticized for the following but I will still say it. I think our chances of getting lowland snow and or Arctic cold are rapidly diminishing. I suspect more crummy weather that will leave most of us disappointed by the time Mark puts a fork in this non Winter. Climate change has pretty much guaranteed that from here on out mild Winters and hot Summers will be the norm. Some of you may disagree but I believe the facts speak for themselves. In the meantime I hope to be proven wrong but I don’t think so.

    • Doinko - Bethany says:

      Climate change does mean winters will gradually warm, but it definitely doesn’t mean we can’t see cold/snow events in February. 2019 was historic in WA and the southern Willamette Valley. 2021 had a major storm, and so did 2014.

      Models also look very cold starting next week

      • Ken in Wood Village says:

        I agree Doinko. The 00Z Euro looks good at the end of the operational run. There is a strong sign that things will turn colder. How cold and will there be moisture when we have the cold air is still a question mark right now. We’ll know more as time goes on. It’s just a waiting game right now. Time to ride the models 🤪

        It looks like we could see a little wind Saturday. Looks like a small low pressure system will spin up but where will it make landfall is still in question.

        Have a good night. See everyone tomorrow 🤗❄️

    • Jim says:

      Sheesh weatherdan it’s only Jan 20. No one knows what weather may come past the next 7 days or so. Always remain vigilant

    • Scott Reeves says:

      Climate change is a hoax

  17. MasterNate says:

    Purely fantasy.
    For entertainment purposes only!

    • icydaze says:

      Wouldn’t surprise me this year. 20 days ago California was in drought. Looks like el nino will take care of there water needs next winter.

  18. tim says:

    Mt snowpack in the cascades is now below 100% , we need cold troughs coming down from the NW to get the snowpack back to normal at least before the summer extreme heat arrives.

  19. Doinko - Bethany says:

    Canadian is very cold

  20. lurkingsince’14 says:

    Folks over at the weather forums seem pretty stoked about what the models are showing in the 10-14 day range 🥶 ❄️
    Curious what Mark sees as it gets closer…

  21. gravatarhojack says:

    Thanks Ken for sharing that PNW weather by Michael. My new go to! I really wish Mark did this. He once joined in on his blog to answer questions and keep us updated but its now just a distant memory…

  22. tim says:

    Cliff mass says the California drought is over but the u.s drought monitor says California is still in a severe drought, the world may never know.

  23. Roland Derksen says:

    A touch of frost here this morning, and the possibility of some mixed showers(rain/snow) tomorrow, so winter’s not quite finished. Even if February turns out snowless, I can still see a chance of measurable snow in March.

  24. Ken in Wood Village says:

    I thought I would post Michael’s outlook. There is something interesting the Euro is showing for the low pressure system for this Saturday.

  25. Andrew says:

    I know the pattern change will eventually expose the region to colder, continental air, but not seeing a true cold snap yet in ensembles. There are a handful of cold ensemble members but no obvious signal of arctic air. That’s not uncommon though. Pattern change is first domino. The trajectory of polar lobes (as Michael Snyder calls them) is pretty hard to pin down this far out. Still hoping for some action but no eye candy yet.

  26. Roland Derksen says:

    Nice to know there’s going to be a break from this dreary pattern. I went for a short walk to the local Safeway store here this morning: fog , steady rain and dark. January weather at its least likeable.

    • Joshua Lake Oswego says:

      Then there are those of us sadists that think that is perfect winter weather.

      • X (Aumsville OR) says:

        Anyone ‘excited’ about the prospect of 110F coming this whole summer and half the state ‘mysteriously’ on fire giving extremely unhealthy air by August? 😲🤣🤮🪓

      • Roland Derksen says:

        Oh sure… I can think of places up the coast that get that kind of weather almost all year long.

  27. Ken in Wood Village says:

    I thought everyone would like to see what Michael Schneider’s post for today and the extended forecast.

    • X (Aumsville OR) says:

      Most of the time he’s clickbait like those ‘Nintendo Switch News’ guys: they fail to get ‘started’ till about the 3 min mark then repeat a lot to I guess meet a certain time usually 12 mins. What they otherwise could’ve said in 6 mins

      • tim says:

        He does make money with his YouTube channel so it’s a scheme.

        • JohnD says:

          He is extremely adept at what he does, guys. Wide ranging professional credentials. And a nice person/family man as well. Professional jealousy is petty at best.

  28. Patrick says:

    At least it doesn’t look like the high will park right over us and get into a temperature inversion setup, with low clouds and fog hanging around all day, at least in places away from the gorge. Need a break from the rain.

  29. WEATHERDAN says:

    I really don’t see any Arctic air in our future. However I do see a lot of freezing nights and cool days in our future. At least it will feel a lot more like Winter then like it has so far this month. And who knows we might just get that Arctic air after all. Peace.

    • X says:

      I never did see any. The dynamics were all wrong but ‘The models say so!’ crowd took over any legit thinking.

  30. Gregory Carstens says:

    Hi Mark

    I post the daily synopsis on my group CASCADE OLYMPIC WEATHER at least once daily from NWS Seattle and I have noticed the pattern shifting in the discussions at times and other times not so much. In fact the other day I did not even post the NWS Seattle synopsis on my group because it was so vague. I see the pattern change coming in the NOAA models from the CPC and El Nino conditions are favored for around July-August-September. We are over due for a quiet winter.

    Greg in Centralia, WA and Admin for CASCADE OLYMPIC WEATHER a WRN Ambassador

    Sent from Outlookhttp://aka.ms/weboutlook

  31. Ken in Wood Village says:

    Thanks for the update Mark 😉 I like the fact he only goes out to the 25th and 26th. That’s when the models start to show the high pressure system retrograde to the West more to let in some Arctic air. I know it’s a long ways off in fantasy land so we just need to wait and see if it happens. 🤗❄️

  32. JohnD says:

    Thanks Mark. Great stuff as always. Good changes ahead. Hopefully that trend continues to evolve beyond the 25th!

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