Monthly ECMWF Maps

Just saw the weekly 500mb height maps from last night’s monthly run of the ECMWF.  Ridging wants to hang around the West Coast much of the 2nd half of December.  Here is the first week showing the troughs impacting us at times.  They are weak and splitty, evidenced by the highest anomaly to our south.  This is bad for skiing, no significant snow (2 feet or more) on the way:


Then Christmas Week a change back to the November pattern we saw with ridging hanging right over us or trying to shift back a little to the west.  We turn very dry, although the ECMWF today has warm rain in the Cascades as the ridging is getting established Sunday through Tuesday next week:


It’s interesting to note the ensemble average seemed to be farther west yesterday, putting us on the edge of “backdoor” arctic air invasion.  Even the 12z ensemble average that just came out midday looks like that.  Slightly under two weeks from now:


Back to the monthly run…Week 3:


A bit more north with the ridging, this could let some systems through underneath it…into mainly California.  We saw this in November a bit.  Mild West Coast and cold eastern USA.

And the final week which takes us almost to mid January…looks a classic “El Nino” setup again with a strong jet into California and the ridge has moved farther north.  This could be wet at times over us, similar to what we’ve seen early in December.


Remember this is just one run, although it is many different ensembles averaged together too.  The main message I take away from this is the ECMWF shows no cool/snowy westerly-flow pattern for the Cascades in at least the next 2-3 weeks.  That was totally absent last winter as well.  At least until the floodgates opened the 2nd half of February!

I’ll probably blog more on the pitiful (and possibly record-setting) state of the snowpack in the Cascades late today.

Chief Meteorologist Mark Nelsen

23 Responses to Monthly ECMWF Maps

  1. 18z GFS Parallel(Upgrade) 500mb pattern looks pretty decent. Although I’d prefer it a bit further west, I like seeing the ridge orientation/configuration with the height anomaly nosing into southern Alaska and block amplified up through Alaska/western Yukon. However, we do not see ridging over the southeastern U.S., at least not on this run. It’s still promising nonetheless.

  2. Mark,

    Remember this?

    Rob – Southeast Portland says:
    November 5, 2014 at 3:16 am

    Ski Resorts won’t open until Christmas. Book it. Write it down.

    God I hope I am wrong.

    Mark Nelsen says:
    November 5, 2014 at 8:17 am

    Let the record show…I just did…3:16am November 5th!

    Sadly we might both be wrong as there’s a decent chance it’ll be in January now.

  3. Because why not?….
    [Model Countdown]
    00z GFS 2 hours 10 minutes
    00z GEM 2 hours 24 minutes
    00z ECMWF 9 hours 37 minutes

  4. I saw the El Nino pattern coming about a month ago. Some were not ready to punch the ticket and hop on the train just yet then though. I think things are much more convincing now based on where snow totals are in the Cascades from Mount Baker to Crater Lake. They are pathetic looking even in the higher elevations. The continuing wetter pattern in California along with the snowfall in the Sierra correlate well to at the very least an El Nino pattern even though I don’t think anyone has officially declared one taking place just yet. 🙂

  5. WEATHERDAN says:

    If and I say if we have a record low snowpack this Winter then next Summer really worries me for several reasons. First off would be a lack of water for drinking, also a lack of water for farming. A lack of water in the woods means a greater chance of wildfires earlier than usual. It also stresses out trees which leaves them more susceptible to disease. It also means a greater chance of another hot Summer. Also recreation will suffer. Now a lot could happen between now and next Summer. But if January and February resemble November and December we will be in deep doo doo. What is interesting is that most of the whole Northern hemisphere is way above normal as far as temperatures go. It’s too early to jump off the cliff just yet. But if Winter doesn’t appear by mid January and charts show no cold weather in sight by the end of the month, then yes stick a fork in Winter because it will be done. Merry Christmas to all and to all a good day. Peace.

  6. Jason Hougak says:

    If I could afford a ski boat I wouldn’t have to be concerned about the snowpack…. until the rivers and lakes are dry.

  7. If its this crappy in the mountains early then it will be great later on.

    • Jason Hougak says:

      Optimistic in November has become nail biting but it is December. We need to find old man winter and invite him over for winter before it’s too late.
      ” Save the clock tower!”

  8. Jason Hougak says:

    GFS and ECMWF now showing everything has shifted east since yesterday.

    • Chris s says:

      Don’t lose hope yet. Like mark said the ensembles are really close to a backdoor setup. Let’s not jump ship yet….. Although we are close to cliff jumping!! Lol

    • Jason Hougak says:

      Punch bowl falls is a great one to jump!

    • Sapo says:

      Actually today’s 12z and 18z GFS are pretty cold…the type of cold pattern we had twice in November this year, not backing off from previous runs. If I had to say, I think the 12z GFS was actually a bit colder than the earlier runs. GFS about -4/-5 for the Christmas timeframe, but with the east winds there could be a potential for something…? The GFS ensemble is in pretty strong agreement that we’ll experience some kind of cold on the 24-26th about, ensemble members mostly are about -3/-6, decent. A little improvement and we could have a cold (but not necessarily white) Christmas! Haha it’s still about 216-240 hours out but still something to watch.

    • Sapo says:

      Why does it say my comment is awaiting moderation? I’ve been on here for awhile, idk why its not letting me comment.

    • Sapo says:

      This comment didn’t say so…whatever.

  9. Jason Hougak says:

    My stomach feels like Chunk in the Goonies…

  10. W7ENK says:

    Ask, and you shall receive. 😆

  11. WEATHERDAN says:

    First. Peace

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