First rainy/windy system of the season will be followed by unusually chilly November temps

8pm Thursday…

It’s about time for a blog post! I’ve been very busy the past few weeks; meetings, school visits, new weather branding (more on that below), and working on graphics. Plus we’ve added some time to our evening broadcasts, so…real busy. I strongly recommend you follow me on Facebook @marknelsenweather and Twitter @marknelsenKPTV because I regularly post on those platforms. Plenty of maps, models, and thoughts when I’m working on those sites. Blogging takes quite a bit longer, I need a good chunk of quiet time to do this…my kids would say that’s “because I’m a boomer”. Whatever.

QUICK RECAP OF RECENT WEEKS

October DID end up as Portland’s warmest on record, as did September, and August. All 3 were Portland’s warmest. Of course August was also the hottest of ANY month. We ended up with 12 days at/above 80 degrees (yellow outlines below) and even with the sharp change to cooler/wet the last 10 days of the month we STILL ended up about 6 degrees above average!

I had some people ask me either on social media or email if “the rain will ever come back this winter”. Most likely new transplants; the rain ALWAYS COMES BACK. And that happened in late October. That’s why I somewhat ignored those that were complaining about the 4 months of mainly dry weather. Yes, fires were starting to pick up again after the showers in late September, but we avoided a big east wind episode that could have led to lots of trouble. We ended up with close to normal rain by Halloween evening. And sorry about that Halloween soaker; those have been rare lately

WHAT’S AHEAD

The cooler weather and lots of rain hasn’t surprised me at all. But now it appears we’re headed toward much cooler than normal weather next week. If models are correct, this will end up being the most dramatic change I’ve seen in the fall; from 80s to highs in the 40s (or colder?) in just a few weeks.

Tonight we’ve got an atmospheric river setting up across the region. That’s due to a strong westerly jet stream approaching the coastline. This is the view from jetliner altitude tomorrow…about 30,000′ or so

Then Saturday…a 200 mph jet stream right over us!

Then by Monday a deep upper-level trough has dipped south out of Canada and is just offshore. That’s cold. So we get lots of rain through tomorrow night, then showers Saturday, a colder/wet system Sunday, then back to scattered (even colder!) showers Monday.

THE RAIN

How much rain? Models have backed off just slightly the past 24 hours. This will be mainly a “nuisance” rainfall in the lowlands, especially south and west of Portland. A collection of model forecasts

And the highest resolution model available to local meteorologists; the UW 1.33 km WRF-GFS (from the Huskies of course!). You can clearly see a very sharp rain shadow in the lee of the Coast Range. Less than 1″ around Hillsboro tomorrow, but up to 2.50″ central/east metro areas. I could see some water over a few roads if we do get 2.00″ or more in spots. Heaviest rain will be in the evening.

(kptv)

Another view of the heavier rain in the aptly named “Waterfall Corridor” in the Gorge.

THE WIND

A gusty southerly wind will accompany the atmospheric river/pineapple express tomorrow. That’s normal for these events and in this case it won’t be TOO strong. I think gusts 30-40 mph are likely in a few spots anytime tomorrow. Wind will come and go all day, but should be strongest in the evening just before the cold front passes through between 8-11pm. Normally that would just give us some isolated outages, but there’s a complication this time. You’ve probably noticed leaves have been very slow to change or drop off this year, due to the record warm 1st half of fall. So we’ve got a bunch of extra “wind-catchers” on the trees and I can see that adding to the outage count tomorrow. Regardless, especially if you are in a rural area, keep in mind the power COULD go off in your neighborhood tomorrow.

FOX12 FIRST ALERT WEATHER

For over 15 years at FOX12 we’ve used the branding “First Live Local” for our weather forecasts. It’s been time for a change for quite awhile, plus we are now part of the Gray Corporation. It’s nice working for a company that owns lots of TV stations and knows what it’s doing. So, we’ve taken on the First Alert Weather branding that most other Gray stations use. And I think it’s a good change. I’ll admit that sometimes I get a bit lost in the “meteorological weeds” during a weathercast and this will help focus things a bit more with most important information right up front. Apparently you can teach an old dog new tricks…

When a specific day shows up that really sticks out weatherwise (tomorrow?) we’ll draw your attention to it by marking it as a “First Alert Weather Day”. If we do it right, these should be days in which weather will significantly disrupt your plans or day. Tomorrow is a bit marginal for that; we’ll see how many outages we get and whether local flooding shows up in spots. We have specifically avoided using the terms WATCH, WARNING, or ADVISORY because those are used by the National Weather Service. This is NOT a replacement for those official watches/warnings/advisories! You can learn a bit more from this 2 minute video: https://www.kptv.com/2022/11/02/first-alert-weather-new-way-stay-ahead-weather/

COLDER WEATHER AHEAD

That cool upper-level trough I mentioned earlier drops down along the West Coast and sits there Monday through Wednesday. 850mb temps bottom out around -4 to -6 C during that time; unusually cold for early November. Typically that’s around 1,500′ to 2,000′ snow levels. That’s with onshore flow. But during that time next week, we get a cool north or northeast wind as a cold arctic high pressure area will be sitting over SW Canada.

The low level airmass will also be unusually cold, including north of us. Here’s a Wednesday morning forecast temperature map; keep in mind anything under about -17 (C) on this map is 0 (F). Very unusual to have temps around zero degrees in early November just north of the U.S. border.

With that chilly air filtering south, snow levels COULD dip all the way to sea level. But at the same time it appears we’ll likely be dry from late Monday through at least Wednesday next week. So I’m thinking sticking snow down to sea level is unlikely Monday through Wednesday. It’s a bit too warm still Monday morning, but then when it WILL be cold enough Tuesday/Wednesday we’ll probably dry out. Now later next week, we could see moisture return. Each model is different with timing so we’ll see what happens. Remember that it IS possible to get snow or freezing rain as we head into mid-November. In 2014 freezing rain made it all the way into the central part of the metro area on the 13th!

That’s it for now. Our forecast looks like this…with high temperatures 10-15 degrees below normal Monday-Thursday next week. Stay Tuned!

58 Responses to First rainy/windy system of the season will be followed by unusually chilly November temps

  1. Ted Harris says:

    Mark: comments disabled on the “legacy site” post, so leaving it here…. the newer site has SO many trackers. Ooof. Okay, fine. I can block those. But it’s notably missing an RSS feed. Any chance you can influence one to appear?

  2. Opie says:

    Surprisingly wet again in Salem this morning. About an inch so far and still coming down.

  3. MasterNate says:

    Radar problems? Its been coming down for an hour but doesn’t show it on the radar.

  4. Andrew says:

    Man I really hate wasting this pattern in early november. like three weeks later I have to think this would have been a snowmaker. oh well.

    • Tanis Leach says:

      One of the top analog years I had was 1985-86. There was a 2nd coming of winter in February, in addition to the coldest December on record, after a November arctic blast.

      Though getting this in January would be better.

  5. Doinko - Bethany says:

    Backdoor arctic blast on the 12z Euro

  6. Andrew says:

    Both models appear to still support snow showers around portland metro by this evening. temps marginal but flakes seem very possible. GFS still very cold this week as things dry out. Struggling to see how that verifies but GFS has been impressing of late. There is a lot of cold air to our north. I don’t take for granted that these patterns often only emerge a few times during cold season.

  7. Tanis Leach says:

    6″ at 1400 feet Vinyard mountain at 3:30 pm
    1/2″ in Corvallis so far.

    • Doinko - Bethany says:

      Really impressive for measurable snow in the day on November 6th. CVO was between 32 and 33 from 1-5pm! Looks like they’re down to 32 now.

  8. Brandon Johnson says:

    It’s snowed in sandy a few hours ago. I’d say a little over a inch accumulation. Temp is holding around 34-35. It’s been melting since but was cool to see! I’m just over a 1000ft where I live

  9. OSUfan says:

    GFS was right it’s snowing legit in Corvallis!! Winter comes early this year peeps!!

  10. Roland Derksen says:

    Rain changed to snow here for the past hour, and some was starting to whiten the grass boulevards along the streets, but it’s stopped – at least for now. Have to get down at least 2F lower if this stuff is going to stick around.

  11. Doinko - Bethany says:

    Snowing in Corvallis and Eugene in some places, looks like some sticking near Junction City

  12. Doinko - Bethany says:

    KEUG is reporting rain/snow/mist right now

  13. WEATHERDAN says:

    Today’s weather in a word bleeppp. Peace.

  14. ocpaul says:

    Happy Sunday! Snow and rain mixed here at 650′ in Boring. 39 degrees. Hope this portends a great Fall/Winter. We’ll see…meanwhile “let it snow, let it snow, let it snow” (and accumulate)

  15. Chris says:

    Mix at 400 ft in Gresham

  16. Opie says:

    It’s been a deluge in Salem this morning. Loving every drop!

  17. tim says:

    La Nina is now weakening as forecasted and will continue that’s great news for California and the SW they really need the rain

  18. Roland Derksen says:

    It’s amazing how stark a contrast these past 2 weeks have been with the previous ones for me: The last 2 weeks(Oct.22-Nov.4th) I’ve measured 10.19 inches. The previous 14 weeks, just 0.96 inches. And now tonight, we have a snowfall warning. I could see up to 2 inches on the ground by tomorrow morning! Most likely, it won’t amount to that depth, but if we get half an inch or so, it’ll be the most I’ve seen accumulated before November 11 since 1991.

  19. Andrew says:

    Models seem to be trending slightly warmer for next week. Still unusually cold but nothing that will constitute an “event.” I’m still going to be interested in the runs over next 24 hours just to see if they flip back but the moderation in temps seemed fairly inevitable. Thankfully it’s not even winter yet!

  20. WEATHERDAN says:

    On October 15th Salem hit 92. Next week we might see snow at least in the air. Never have we had such a quick turnaround. I believe we are in for a very active Winter.. One like we haven’t seen the last few Winters. Only time will tell. Peace.

    • MasterNate says:

      Today is a good start. We are due for a good wind storm. Cheers to a fun snowy winter!

      • X says:

        It appears the atmospheric ‘storm’ of the century pulled off the ‘usual’ 90 degree turn and went up to northern WA based on the amount of outages reported north of Seattle.

        A few small gusts here in OR but nothing crazy we haven’t seen before. Even last year I think was a bit winder. Rainfall totals are fairly decent now the front is coming thru?

      • X says:

        Everett WA is blacked out with smell of burnt electronics. A poster said the port barely has any working lights now. It’s good night for them it seems.

  21. Doinko - Bethany says:

    Potential for the block to redevelop in an optimal spot for us mid-month!

    • Oliver says:

      I’d take copious amounts of cold rain and heavy mountain snow over blocking that may or may not deliver the goods. It seems like the last few years we have had so much blocking and more drought and ridging conditions. We need zonal for months on end

      • Anonymous says:

        No thanks.

      • Joshua Lake Oswego says:

        My man! Cool, moist zonal flow for months on end sounds perfect.

        • Michael says:

          Yes, that sounds terrific. So much rain and cold that the economy cools off with it and brings Oregon back to the way it was… very quiet, slowed down and all the Helots move away.

        • X says:

          Annual ski pass people would be jumping up and down for joy unable to contain their glee and so would the ski resorts especially the small mom and pop ones.

    • tim says:

      Summer to winter then back to summer all in a month.

      • Doinko - Bethany says:

        What do you mean back to summer? That’s a very cold pattern

        • Chris says:

          He’s just being difficult. It’s cute.

        • tim says:

          November cold means a mild winter followed by a early spring nine times out of ten, 45 years of experience proves that , kids just don’t understand.

        • Doinko - Bethany says:

          Some examples that prove you wrong:

          November 2017: February 2018 snow/cold
          November 2010: February 2011 snow/cold
          November 2006: January 2007 snow/cold
          November 1996: December 1996 big snowstorms in WA
          November 1978: January 1979 was very cold
          November 1985: Some snow/cold in February
          November 1955: Very cold and snowy winter followed

        • You’re gonna have to excuse Tim. He doesn’t really have a clue what he’s talking about. just making stuff up as he goes along cuz he’s likes trolling ya’ll.

    • JohnD says:

      A PERFECTLY placed ridge is fine by me! All the heavy hitting winters have had them. After that the lows can sneak in when they will.

  22. Evan -- Cedar Mill says:

    This is pretty much a non-event. I’d be shocked if we get below 30F.

  23. Roland Derksen says:

    Some mixed rain/snow here last night, but temperatures are rising now. Good chance to snow though, next week.

  24. GFS has finally come around to the ECMWF’s solutions, showing coldest highs on the 06 and 12z to be near 40 with lows in the mid to upper 20’s. That’s still exceptionally cold for this time of year.
    0 precip after Tuesday too, so becoming highly unlikely that a transition event occurs.

    • Andrew says:

      EURO slightly more bullish on precip than GFS, though I agree both models are pretty dry tues-thur. I don’t think a transition event anytime thurs-sat is completely out of question, depending of course on how much cold air we get. Interestingly, the general cold pattern persists well beyond just a few days next week. Temps should start to climb enough for sea level snow to become unlikely by next weekend, but still well below average and favorable for snow as low as 1500 feet for foreseeable future.

  25. lurkingsince’14 says:

    Thoughts on potential for foothills snow (~1300ft) next Thursday-Saturday? Have a trip planned, looks to be marginal but want to be prepared.

  26. Ken in Wood Village says:

    One thing that bothers me the most when we have a weather event is when you want to use something and it’s down 😠 I’ve been trying to see the satellite images for animation and I can’t use it to see where the front is 😒

    Well, I’m at work and we have been having some good winds and a lot of rain. It’s suppose to get worse as the day goes on so this could be a fun day…lol.

  27. Andrew says:

    Pretty big discrepancy once again between GFS and EURO for next week. They started to come together during the midweek runs but not anymore. GFS is really cold. If it confirms, there is a decent chance that’s the coldest air Portland area sees all “winter,” which is absolutely wild considering it was 85 degrees less than a month ago. The EURO is cold but nowhere near the GFS – highs in low 40s, lows high 20s. As Mark notes it’s really going to come down to how cold the air is to our north and how much filters down into our region. This has the potential to be the ever elusive north to south cold push that flirted with portland last december but never truly got here. I’m still a bit skeptical but the ingredients are definitely emerging. And as we know from previous experience that dry continental air can really entrench and take a while to clear our, something models really don’t reflect well at all. I’m not terribly knowledgeable in this area but I would guess the sun angle in early/mid november has a pretty similar effect as it would in early/mid february. That is to say if cold air is in place there really isn’t a reason portland can’t have a winter weather event that early. Its maybe not as optimal as late December but still very much in the zone of possibility. I still view the April snow event as much more of an anomaly as getting something the second week of november.

    • Doinko - Bethany says:

      The 500mb pattern on the GFS and Euro honestly look pretty similar, the GFS just thinks the air mass will be much colder. A good thing is it looks like both runs show cold air settling in the Columbia Basin which could bring a gorge component.

      • Andrew says:

        Yeah totally. a freezing rain event in second half of next week is not out of question either.

  28. Patrick says:

    Its fine, the so- called atmospheric river will last about 12 hours , in my estimation, then sag south, which is awesome for southern Oregon, but who knows really

  29. Doinko - Bethany says:

    GFS OP is pretty bad but the ensembles are cold, mean 850mb temp of -15c in the Dalles

  30. Paul D says:

    “below normal” is music to my ears! It’s payback for the nasty summer!

  31. tim says:

    I don’t see this being the theme all winter because la Nina is forecasted to weaken to neutral by mid winter therefore we’re getting the cold and possible snow now in November. That’s not being unreasonable but anything can happen of course.

  32. runrain says:

    2nd comment of the First Alert era! At least tomorrow will be a bit milder before the chilly air sets in.

  33. Carl says:

    East wind next week?

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