Midweek Vacation Extra

Here is a note I sent to a few weather friends last night around 10pm…Too bad I didn’t take the time to put it on the blog too, but hey, I’m on vacation this week.


I”ve been out of the loop, trying to forget weather for a week while off.  But I just looked at 12z and 00z info and I don’t see how the metro area could get freezing rain tomorrow.

1.  Very little moisture at first.
2.  Airmass coming through the Gorge is barely cold enough to get freezing rain to Troutdale.  Corbett is 30 this evening with a dewpoint in mid-upper 20’s.  It needs to be 28 or less there as the precip starts to get freezing rain into Troutdale, at least that’s what I’ve noticed in the past.
I’d say 33 for at low at PDX tonight, but a quick rise to 35 when precip starts at midday (00z ETA doesn’t have it here until afternoon).
I think this will be a bust.  Just doesn’t look cold enough with precip even arriving at the right time…okay maybe a pocket or two if precip arrives before 10am, but freezing rain needs a sustained inflow of cold/dry air to continue more than an hour, and I don’t see that anywhere other than Troutdale east…

308 Responses to Midweek Vacation Extra

  1. Andrew---Ellensburg, Wa and Portrland, Or says:

    arg, i just can’t decide if it will snow or not. This is going to be VERY close.

  2. Max - Fairview says:

    New 7-day up with a snowflake for early Wednesday morning.

  3. Justin- Brush Prairie says:

    Sure timmy, I just want to get the facts straight here. For one, nothing on the 00z GFS shows the low coming in south of Newport, in fact the GFS finally agrees here with the NAM and shows a northern coast landfall, NAM now even thinks perhaps around Astoria. I think these are facts that need to be reported here since we’re all drooling over the low, the models clearly are trending north with every passing run.

  4. Andrew---Ellensburg, Wa and Portrland, Or says:

    Timmy, i don’t think this is a “us” and “them” blog. Everyone has their own thoughts.

  5. Justin- Brush Prairie says:

    What are you talking about south of Newport? Look at 30 and 36 hours, it shows the low at 997mb, weaker than previous runs, around Tillamook moving ENE, passing over Clark County. I’m sorry but get real here, we have no chance of snow ahead of this low, 00z GFS/NAM basically confirm that for me. We WILL have cold enough 850mb temps AFTER the moisture runs out. 00z GFS gives us our only chance for snow between 42-48 hours, with some scattered showers behind the front, NO CHANCE before then.

  6. timmy - scappoose says:

    thanks for joining us justin, its nice to have someone who feels the same on this one.

  7. Derek-West Gresham- says:

    Looks fine to me as well. -7 850mb with precip is snow. But oh well, we will see how it happens.

  8. Andrew---Ellensburg, Wa and Portrland, Or says:

    I was on the snow wagon at first, but am starting to doubt it now. Seems the models are taking the low further north giving us less of a chance.

  9. Justin- Brush Prairie says:

    Okay, I’m here at home, just came back from dinner with relatives. I’d say right now this is looking like a repeat of December 1, 2005, only the low may landfall a little further to the north. Why I say that is that we simply won’t have COLD enough air east of the Cascades, td’s in the Columbia Basin look too warm to suppor evaporational cooling, and temps themselves will be horrendous. The cold upper level support doesn’t arrive until AFTER the low passes to our SE, at which point thhe lower level moisture promptly runs out. Could a few light snow showers be possible Wednesday afternoon/night? Maybe, but I don’t see any overwhelming signs. A weak deformation band paralell to the low may also be possible, but if we want that OVER US then we need to NAM solution to the north to verify, right now that’s the only chance I see with this for sticking snow around PDX, may get some wet flakes Wednesday morning when the low is over us, but sticking appears very unlikely. I’d put the chance for sticking snow in the valley at 10-20%.
    After that, next weekend/week looks interesting, dare I say I am already seeing some similarities to late December 2003 with this cool and stormy pattern? But for now I am comfortable calling for NO STICKING SNOW anywhere in the Portland area with this WEednesday system.

  10. Jerry says:

    00z is looking good. 🙂

  11. Derek-West Gresham- says:

    GFS ends up taking it just south of Portland because it shifts the low a bit north. But what it does is shift the center north as its coming inland, something that wont happen if the low is stronger, which it will be. 🙂 So the low will come inland about where I have said I still feel. Even if it does go just to our south the models still give us heavy snow Wednesday.

  12. Derek-West Gresham- says:

    Looks like new 00z GFS is going to send it into Oregon south of Newport a good ways. Don’t doubt, its coming!

  13. Derek-West Gresham- says:

    Impressive satellite with rapid strengthening right now, I estimate the low at 992mb currently.

  14. Derek-West Gresham- says:

    That low was ALREADY 995mb at 4pm and has since strenghened rapidly. Already WAY ahead of strength models had it, VERY good sign.

  15. timmy - scappoose says:

    yeah i have been looking at the weekend as well, it seems more impressive than a lot of these snow teases so far this season. but is still 6 days out. will have to wait.

  16. Derek-West Gresham- says:

    GFS took that out in the 18z run but has been toying with it. Well -6 to -7 but yes.

  17. Jerry says:

    Check out hour 168
    IS that -7 to -8 850mb temps over the willamete valley with northly flow?

  18. Derek-West Gresham- says:

    Ok Steve. As with the last one I am going to trust GFS over NAM for track. And your correct sort of Timmy. Its going to produce its own cold air as it comes inland as is the case with strong low pressures, count on it being 10mb stronger than GFS has at least. I recall the last windstorm had it at 980mb while it strengthened to like 968mb or 970mb or something like that.

  19. Steve Pierce - Vancouver says:

    Tim: Cool!
    Derek: Let me get out of here (Clackamas) and get back hime in Vancouver and I will post in the 9pm hour after the MM5 is done. So far the NAM MM5 run is finished out to 30 hours and it takes the low right over PDX and only birngs it in at 995mb. That is a lot weaker than the previous run. The GFS has not started yet.
    There is one more thought. Maybe this deepens even more so than models predict and the low curves north up the coast. That would be very interesting for the wind lovers out there.
    More later!

  20. timmy - scappoose says:

    the track of the jan. 1st storm was further south, sexton summit, not far from the cal. boarder. and the air with this one will not be as cold, i really dont see the L pulling in that cold of air. just cool.

  21. Derek-West Gresham- says:

    Here is snow over PDX at 10am. NAM has low moving over PDX, will go south of there I am quite sure.

  22. jake says:

    does the NAM still have it making landfall around astoria?

  23. Derek-West Gresham- says:

    So Steve, what are your current thoughts based on location, elevation, and storm track. Any thoughts would be helpful. You may have noticed low is a bit south of where models put it so it should landfall a little south as well.

  24. timmy - scappoose says:

    yes i corrected myself afterwards.

  25. timmy - scappoose says:

    i repeat the chances of snowfall are not good, im suprised so many models are showing anything.

  26. Steve Pierce - Vancouver says:

    I am not one to normally correct people on this site, but you made a comment earlier that I just wanted to correct / clarify.
    About 2 hours ago I posted something on the blog comparing this event to the Jan 1, 2004 event. What I was referring to was the sneak snow storm we had on New Years Day, with no arctic air in place. Vancouver had 7″ that day. Then the door opened from the north on the 3rd/4th and that is when we got the real cold stuff in here prior to the overrunning event two days after that.
    Do you see which one I was talking about now?

  27. Derek-West Gresham- says:

    Thats true, and GFS WILL place it further south. Has been the trend all along and will continue with 00z. Low is still south of where NAM says it should be right now so I have no reason to believe its solution of low placement will be correct. Low will be a little further south.

  28. jake says:

    why is the IGES showing virtually nothing as far as snowfall? All the other models show at least a small amount

  29. -100F says:

    Well anyway, the NAM sucks at the placement of lows compared to the GFS.

  30. Derek-West Gresham- says:

    It does -100F, but it also gives us -7 or so with heavy precip. It dumps all of Portland with 3+ inches of snow.

  31. -100F says:

    Apparently the 00z NAM takes the low farther north, this weakens our chance of snow. Hopefully the 00z GFS takes it farther south.

  32. Jerry says:

    I think before we hype we should look at a couple more model runs. We dont want this thing to go any farther north.

  33. Derek-West Gresham- says:

    Lets not forget that that thundersnow a week or two ago produced sticking snow at -5. This could be convective as well at times so it may be good. 🙂

  34. Derek-West Gresham- says:

    -5 is cold enough for sticking snow at my place, so yeah its cold enough here.

  35. jake says:

    not until they issue a weather advisory or waning

  36. Andrew---Ellensburg, Wa and Portrland, Or says:

    They show 3 inches of accumulating snow at 1,000 feet and above so far.

  37. timmy - scappoose says:

    the nws curse.

  38. Andrew---Ellensburg, Wa and Portrland, Or says:

    NOAA now calling for rain/snow mix wednesday!!!!!!!!!
    Tonight: Mostly cloudy. Chance of rain showers. Probability of measurable precipitation 40 percent. South wind 6 mph. Low 35.
    Tuesday: Ocasional rain. Probability of measurable precipitation 80 percent. Southeast wind 12 mph. High 42.
    Tuesday Night: Rain. Probability of measurable precipitation 90 percent. Northeast wind 10 mph. Low 34.
    Wednesday: Mixed rain and snow. Probability of measurable precipitation 90 percent. Northwest wind 14 mph. High 39.
    Wednesday Night: Mostly cloudy. Chance of rain showers then patches of fog. Probability of measurable precipitation 30 percent. Low 31.

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