18z Models In…Not Much Change

1pm Thursday…

Here’s our latest forecast in a prettier form than the previous post

MarkSnow_TextPanel

And look at this morning’s low temps, the coldest of the season for almost everyone.

PLOT_Lows_Metro

The east wind spots have been colder this season.  The breeze keeps the temperature up, thus the 26 for  a low at Troutdale.

All 18z models (that I use) are in.  This is what I see:

Slightly closer precipitation to the metro area on the 12z ECMWF, but still dry here…it’ll be close!

ecm_12z

18z RPM is almost exactly the same as the 12z RPM at the closest approach to the northern valley, first the 12z, then the 18z:

RPM_12z RPM_18z

But the 18z NAM is definitely a little closer to us.  Compare the two maps:

nam_12z nam_18z

And finally the 18z text output from the RPM.  Check out that cold air!  Notice how it goes perfectly calm Saturday night.  That’s going to be crazy cold for everyone, especially those with snow cover as mentioned on previous posts.

web_RPM_TextPDX_18z

Probably no new posts until this evening so no model info comes out again until after 7pm.  Stay warm as the east wind picks up this evening!

I’ll be watching observations and radar closely as the surface low is now visible on satellite NW of Forks, WA.  So far flurries have spread down almost to Hoquiam.

Chief Meteorologist Mark Nelsen

 

142 Responses to 18z Models In…Not Much Change

  1. AlexQS says:

    Darn, I left Molalla, OR early today heading for Vancouver, WA. I knew traffic would be slow. Seems it’s done snowing here now, at least for the moment. My wife said it’s snowing in Molalla now. I guess I missed it, LOL. Thanks for the links to your favorite radars Mark.

  2. SnowedIn - North Plains says:

    LOOK! (as ‘poose would say)

    http://www.atmos.washington.edu/weather/radar.shtml

    And it begins…. moisture is moving onshore!

  3. boydo3 N Albany says:

    Already down to 24 here.

  4. No Snow says:

    It is quite amazing with all the technology we have that we can’t even say for sure if it will snow in Portland tomorrow.

    • pappoose in scappoose says:

      I’m glad we can’t. Would take all this crazy panic-stricken fun outta the game!

  5. pappoose in scappoose says:

    NATIONAL WEATHER SERVICE PORTLAND OR
    908 PM PST THU DEC 5 2013

    OTHER CHANGES INCLUDE THE MENTION OF OCCASIONAL FLURRIES ACROSS OUR NORTHERN AND EASTERN ZONES…AS THE 00Z GFS INSISTS THERE MAY BE A LITTLE DEFORMATION PRECIPITATION TO THE NORTHEAST OF THE LOW AS IT MOVES ONSHORE. THIS WILL NEED TO BE WATCHED VERY CLOSELY…IF A DEFORMATION BAND DEVELOPS THERE COULD BE ACCUMULATING SNOW ACROSS AT LEAST THE SOUTHERN SUBURBS OF PORTLAND. NAM CROSS-SECTIONS SHOW A DECENT FRONTOGENESIS BAND SETTING UP NEAR PORTLAND ALONG WITH DECENT Q-VECTOR CONVERGENCE AROUND 15Z FRI…BUT NO QPF LIKELY DUE TO THE DRYING EAST WINDS. IT WILL BE A VERY CLOSE CALL…AND MODEL QPF OFTEN DOES NOT HANDLE THIS SITUATION VERY WELL. ODDS ARE AGAINST ACCUMULATING SNOW FOR PORTLAND…BUT CHANCES INCREASE RAPIDLY THE FARTHER SOUTH ONE TRAVELS ON INTERSTATE 5.

  6. schmit44 says:

    ***COLDWAVE WEATHER CONTEST FOR DEC 6- DEC 10***
    See if you can predict high/low temps the next 5 days at Portland Airport. Enter your guesses at the following thread:

    http://www.directpaintsaleswa.com/DEC2013_COLDWAVE/add.php

  7. W7ENK says:

    East winds starting to pick up here now,

    ENE 4-6 G10

    Solid cloud cover
    27 degrees
    RH 40%
    DP +5F

    My grass is crunchy and the air smells like snow.

    • marcustheweathernut says:

      yeah….. i don’t get much east wind where im at but it definitely smells like snow!!!!!:)

  8. Scott Jett says:

    What about Estacada getting a few flakes?

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