A Warm Ridge

Snapshot  The weather may be boring, but for those temperature freaks, lots to talk about!  A very strong valley inversion has developed across the Pacific Northwest.  As you can see from the image, some spots in the 2,000-4,000' range made it close to 70 degrees today while the valleys sat in the 40s.  The layer of cold air is pretty shallow and has become a bit shallower this evening.  I see the temp on our tower at 1,800' has jumped to 60 degrees at 10:45pm. 

     This is all being driven by a strong upper-level ridge centered over SW Oregon.  Nothing changes the next few days except the center of the upper-level high moves north over Washington by Saturday afternoon.  850mb temps are astounding for mid-January.  They peak out in the +16 to +18 deg C. range.  For kicks, I pulled out the warm season "magic charts" for May and March.  For one, there are no temps that warm for the month of March.  For May, those temps plus easterly wind would get us up to about 90 degrees here in Portland!  So then you might think "we're going to get east wind the next few days, how come the warm air doesn't mix down?".  Well, between now and late February, the east wind is coming in through the Gorge BELOW the inversion top.  It's just bringing in cool air from east of the Cascades, not mixing down warm air from above.  This generally makes forecasting high temps at PDX simple in east wind events in the dead of winter (now).  Except for maybe the 1st day the wind arrives, you can add about 10 degrees from the DLS high to get the number.  Better to remember that in January you're not going to get much above 50 degrees on a good east wind day (except for maybe that 1st day).  45-50 is most common unless/until a good cold pool develops eastside.  I don't see that this time around, so I kept high temps at/above 45 degrees through early next week.

Looks like the surface high is now strengthening quickly in the Intermountain region.  The PDX-DLS gradient has gone from around 2 millibars late this afternoon to about 6 millibars now.  The wind hasn't made it to the Troutdale airport yet, but I would guess it's started blowing a bit up above in "upper" Troutdale and Gresham.  If not, it'll arrive soon.  6 millibars is enough to push wind all the way to downtown Portland by tomorrow afternoon.  With lower dewpoints spreading across the metro area, I have a feeling that tonght's patchy areas of fog will be the last until sometime early next week.  Lots of sunrises and sunsets will be seen from the Portland Metro area through the weekend!  Mark Nelsen

39 Responses to A Warm Ridge

  1. high gust in the past hour is 13.0 i want 30mph

  2. Atmospheric Wrath aka Gradient Keeper - Elevation 300' -Far S.E. Portland- says:

    East wind has surpassed the gusty stage and is now raging 40-45mph (according to my sensor). Corbett is once again at 60mph. We’re now into Wind Advisory levels and I wouldn’t be one bit surprised if we see a Wind Advisory issued before this east wind onslaught is over with. I think Troutdale may gust 46-52mph and Corbett I think will be 66-72mph. Temps in the Gorge and Columbia Basin mid 20’s to lower 30’s fueling a rather chilly east wind. Temp is dropping here despite increasing winds, so that tells me the source is cold.

  3. Tyler in Hazel Dell says:

    Great AMS meeting tonight…packed house (room) too!
    Fun drive home, no fog (and some east wind) from NWS to almost SR 500, then fog to Padden on I-205. After that, on Padden no fog until I crossed St. Johns then the fog is extremely dense and is here as well.

  4. blowmedown says:

    18z has been hinting and showing for two days and now THE 00z. This is a good thing and i believe it’s a bit early(FAST) but i think things will fall into place around Jan 30th to Feb 2nd and if so i find it quite amazing… WINTER WILL COME BACK AND THIS TIME EVEN COLDER!

  5. geo says:

    I have travel plans superbowl sunday(driving that is). Will it be cold/snowy?

  6. u says:

    The 00Z GFS can’t quite deliver the cold air, too much split flow- can’t quite tap into the cold. The 384hr 500mb frame shows potential, still a confused signal this run.
    Still, western WA/NW Oregon get a snow threat out of this, nothing dramatic though.

  7. Mike-multi vill says:

    If you are on this blog long enough you’ll have problems with this typepad. Happens to all of us. Please try again.

  8. Tetraforce says:

    And it’s 33.8F with partly foggy skies.

  9. Mike-multi vill says:

    Hopefully those who attended tonight’s AMS meeting will, share some of the conversation about what the rest of the winter will bring.

  10. Scott says:

    Chucky – if you see a 40% chance of rain in the forecast, do you go for the 60% chance it won’t?
    Has there been a seasonal outlook that goes much higher than 40%? If I think about how they do the maps, there is certainly most of the area where it is equal chances of warm or cold vs. average. I would interpret this as a 50/50 scenario.
    If that is the thinking, then I would think staking an additional 40% on top of what would otherwise be a 50% offering would seem more meaningful than just 60% it could be something else.
    If that is really the case, does it really mean anything at all?

  11. ChuckyD81 says:

    You say that the CPC forecasts are “busting”…when, in fact, they only showed a 40% chance of above normal temperatures.
    You do realize that means there was a 60% chance they would be normal, or…gasp…BELOW normal right?

  12. Andrew (Ellensburg, wa and Portland, Or) says:

    Temperature is dropping like a rock here east side. Had a high of 40 today in Ellensburg, WA, currently 21.3 and dropping fast. Maybe mid teens for tonight.

  13. Tetraforce says:

    Wow Andrew your 1F warmer then me. I am 37.6F and dropping fast.
    This is more like an Elnino then a Lanina. 😦 The weather angels in heaven are beyond insane right now.

  14. cap - Hood River says:

    Cold day. Currently about 32 deg in HR

  15. wendy-silverlake,wa says:

    I have not gotten above 36 degrees for the last two days. Whatever happened to the 50+ degree highs that I saw not to long ago.

  16. Mike-multi vill says:

    18Z is an improvement over 12Z GFS if you like the cold. 384hrs @ 18Z takes us to the end of Jan, next 36hrs the models will see the LRC sweet spot(for PACNW) of Feb 2 -5. I believe we are still on track. One difference between now and early Dec is the MJO signal is stronger. A stronger MJO would be associated with a stronger EPAC jet.

  17. Gordon (Working in N. Portland) says:

    gfs showing back to cold 🙂
    Posted by: yevgeniy.beaverton | Thursday, January 15, 2009 at 03:20 PM
    Anyone else want to chime in on this?

  18. Punxsutawney (aka HIO Phil at work by Sunset High ~280' elevation) says:

    It’s pretty easy to find. If your heading east on 84, just take the 122nd exit. It circles around and you turn right on to NE 122nd heading north. I think it is the second building on the left after NE Marx street and though it’s been awhile, I’m pretty sure it has the round NOAA symbol above the front door. Someone please correct me if that’s incorrect.

  19. yevgeniy.beaverton says:

    gfs showing back to cold 🙂

  20. Atmospheric Wrath aka Gradient Keeper - Elevation 300' -Far S.E. Portland- says:

    Thanks a lot guys (and gals).
    I haven’t had the TV on yet today so just learning of this strange plan crash incident…..
    So back to the weather.
    Amazingly strong inversion continues…
    Horse Creek 3,402′ north Oregon Cascades/Foothills is sitting at 74f ! Meanwhile in sharp contrast Hood River is 33 f and Scappoose is 36 f. East wind has now pushed west to about I-205 and I see Corbett is now gusting near 60mph. The inversion is squeezing the cool air layer thus speeding up the winds. Wondering if Corbett approaches 70mph within the coming days….
    [Surface gradients]
    As of 1 PM——-| +/- Hourly Change
    PDX-DLS: -8.3mb | 0.2mb Increase
    TTD-DLS: -9.8mb | 0.4mb Increase

  21. winter weather monster says:

    he ran into a flock of geese I guess.

  22. Tornado Aly (vancouver) says:

    The only differences I see is that in the Dec map the high in California was more North than what is showing on the Jan 28th map. Also the arctic air in the Dec was more East, and the Jan 28th is in Central Canada. The 492 line is certainly more south on the Jan 28th map, making me believe the coldest air is much closer to us than it was back in Dec. There is also a cold air spot in the gulf of Alaska in the Jan 28th map. Certainly more cold air on tap this go around since it is the dead of winter. Now whether it makes it west of the Rockies is yet to be determined. Or we may just get that low from the GOA come down here instead keeping the true arctic air from Canada from reaching us. I’m no expert by any means but this is what I see.

  23. Silverton500 says:

    There is also a lot of “fluctuation” in our beloved accuweather as well. Last night it said I would have a low of 23 on Jan 22. Now it says 27. And they took the little snowflakes off their 15-day forecast. So I guess what this tells me is that things are still in flux.

  24. Gresham Gal says:

    Ditto to Sarah’s comment. The wind out here in SW Gresham is gusty and strong. One of the gusts around 3:30am woke us up. We are at 472ft.
    Rob, so sorry for your loss.

  25. umpire - NE PDX says:

    A. Wrath, my thoughts are with you as well. Also good to see your observations regarding the east winds, gradients, inversion heights, etc.
    As I recall, the models started being consistent about 10-11 days before the December cold weather. I remember most were surprised about how consistent the models were ten days out. If we are looking at a 50 day (plus/minus a day or two) cycle, then models probably wouldn’t come together until around January 20-24. This gives us a chance to enjoy the sunshine, clean up our yards from all the tree debris, and restock our firewood piles.

  26. Sean (Lebanon, IN) says:

    Tornado Aly – Currently it’s -3F as of 1pm (Wind chill at -20) and that’s with 100% sunshine. We might hit 0, before the sun sets. Currently forecasted to hit -15F tonight, but at my house we could be pushing nearly -20F.

  27. Jake in the Valley says:

    As of 11am CST, every reporting station in Minnesota is below zero!!
    Not many microclimates there right now.

  28. Sarah (E. Gresham) says:

    It’s been reall, really windy here this morning. We had a huge gust around 7:30/8:00 that woke both my husband and I up out of a dead sleep.

  29. Tornado Aly (vancouver) says:

    Wouldn’t call it a bust yet, JohnD. Just delayed. Maybe the LRC thing is onto something… End of January, beginning of Feb.

  30. Atmospheric Wrath aka Gradient Keeper - Elevation 300' -Far S.E. Portland- says:

    Hey thanks so much everyone I appreciate your kind words. In a way you are all like a second family. Thanks Mark! for allowing that to be possible.
    Interesting to note Corbett continues is now gusting to 50mph meanwhile at river level Troutdale airport has no east wind. However if you move just barely south/up from the Columbia River the east wind punches through at about the 100′-500′ elevation range into Troutdale and east Gresham. It is just now starting to develop here…. This is one of the strongest inversions and shallowest east wind I’ve seen.
    [Surface gradients]
    As of 9 AM——-| +/- Hourly Change
    PDX-DLS: -8.0mb | 0.8mb Increase
    TTD-DLS: -9.0mb | 0.9mb Increase
    Rather impressive
    Edit* Wind is just now developing at the Troutdale airport.

  31. Punxsutawney (aka HIO Phil at work by Sunset High ~280' elevation) says:

    I can say Hillsboro sees .10 visibilities on occasions in the fall-winter but I can’t remember any times where it’s been so foggy school was closed, even with the freezing fog that we get at least a couple of times each winter. Or for that matter fog like the Tulle fogs they get in the Sacramento valley where at times you literally can’t see past the hood of your car. A friend of mine was an EMT/Paramedic in Fresno and he had plenty of horror stories about responding to calls in the fog and the difficulty of reaching people. Not to mention the horrible accidents out on the rural roads or Hwy 99 or I-5 down there. Drivers would just completely miss stop signs in the fog.
    I remember driving on I-5 north of Sacramento in January in heavy fog many years ago when the speed limit was 55. I was doing about 55-60 which was probably too fast for visibilities when a guy in a Volvo came out of nowhere and blew by me at probably 75-80mph. A couple of minutes later a CHP came by with all its lights on. A few minutes after that, there’s the Volvo pulled over. If I were that Cop, I would have been pissed to be risking my life to go after that guy; I guarantee the Volvo driver got a ticket, if not a reckless driving citation.
    Some freezing fog reported in Hillsboro this morning but roads were fine.

  32. Sean (Lebanon, IN) says:

    Check this out..
    Hot Coffee tossed into the air at -44.

  33. Tetraforce says:

    As a matter of fact. Have we ever had fog that delayed school and caused serious problems like the Tule fog in California?

  34. mattmann says:

    sorry to hear about your loss wrath 😦
    Hope you and your family get through this with the support of each other and friends.

  35. Mike from Orchards says:

    I’m with you Wrath…a windstorm would indeed be nice…cannot rule one out this winter!….been very stormy in the gulf the past few days….seen a few winters that have combined for snow/cold and a windstorm…like the winter of 1964/1965 and can’t forget 1995/1996 either…..have had windstorms as late as March 27th…like in 1963…..
    It is amazing to have a minus 6.4 gradient and not be very windy…..
    31.4F…..not quite as foggy as it has been here…
    Wrath, Nice to read your blogs again by the way…hope you are feeling better

  36. SnowFlake (Tigard/Bull Mtn) says:

    Typepad strikes again!!!

  37. yevgeniy.beaverton says:


  38. OC 502' says:


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