WxUSAF

You got to be all in all the time this winter. LET'S GO

This is helpful

That 500mb pass is really nice on the Euro. Get that northern stream out of the way just a pinch more and if that slides another 20-50 miles farther south, would be possible to see a changeover back to frozen east of the mountains on Friday morning. Could get some brief heavy precipitation that can drag down some colder air and get a few minutes of fatties.

I think you're in it

FTFY

lol Ukie says you get ~12" with 10:1 ratios.

Kuchera (or Kuchera divided by 2-10) is the way to go with this event.

I'm feeling optimistic that most of us see our first frozen precipitation Thursday. But I'm still very skeptical of any accumulations outside of the mountains or maybe Hoffman's house/Mt. Parkton.

Final spreadsheet 2018 First Freeze Contest.xlsx

Can’t see skewt’s for the FV3 GFS but looks a touch cooler and drier at the surface and a bit warmer at 850 relative to the op GFS. Lord almighty the TT snow algorithm is f-cked up for the FV3.

GFS is probably a sleet/snow/snow grains mix to start with the dry air aloft, but goes over to rain fairly quickly. Probably stays rain/sleet mix for you through 18z. I’m pleased looks like a solid chance of first frozen for most of the subforum.

Euro is still that much slower than the GFS? GFS has precip across the area before 12z Thursday.

ICON calculates snow ratios directly in the model, so what’s shown on TT is not using a post-processing algorithm. It’s still not going to snow 8”.

It me

Heh...I find it interesting, and encouraging, that our warm up keeps getting muted/delayed. Was looking like next weekend, which now has a major arctic blast. Then was looking like around Thanksgiving, and now 18z GFS has a wicked cold shot on Thanksgiving. 10 days out so normal caveats apply, but 18z GEFS is BN through 384. It's all a response to the now forecast -AO/-NAO. Bring it on

Drumroll please! The 2018 Mid-Atlantic First Freeze Contest winner is: @2010 extreme! @2010 extreme won with a total departure of just 9 days, @Cobalt came in 2nd place with 11 days, followed by @yoda with 13 days and @nj2va with 15 days. Our combined average dates resulted in a departure of 32 days.

This is certainly the fastest green-to-bare tree progression I can ever recall here. Basically 4-5 weeks between noticeable color and generally bare trees.

You’re getting about as cryptic as another one of our regular posters.

First freeze contest is over! I’ll post results later today.

26 IMBY and at BWI. DCA hit 32 and RIC down to 29.

Yeah, no way we have a ridge long-term over the Aleutians/Barents Sea given the Pac SSTAs. So it's just a matter of time. You're right of course that our snow climo isn't great the first half of December, but if the pattern keeps evolving in that way, I'd WAG that we'll have chances (insofar as a supportive long wave pattern) during those 1st 2 weeks and then probably some sort of reshuffle after. Who knows though. I still don't see anything I don't like for the winter as a whole, so even if December doesn't work out, let's all remember that's to be expected in a Nino winter.

I don't hate the long range GEFS 500mb look, that's for sure. Scand/Kara Sea ridge builds westward into Greenland as a -ENAO and we start to get some troughing near us. AO goes negative. Only thing that's annoying is that -EPO/-WPO ridge doesn't want to budge much eastward of the Barents Sea. Last night's Canadian ensemble does start to do that, but I haven't seen any suggestion of that in the varsity models yet. Hopefully the Canadian is just rushing it and it will eventually move towards the West Coast. Around the post-Thanksgiving weekend/early following week, the MJO should be rounding the bend back into the favorable phases, which should encourage an eastern trough around 1 December. How persistent that feature will be in early-mid December, assuming it eventually develops, is the big question.

Nope. BWI did though.

Freeze warning up for DC, Baltimore, and SE burbs for Saturday night.

Based on what I hear about the euro weeklies, the pattern evolves as we expect through the first week or two of December and then craps the bed the last two weeks. But whatever, very low skill at that range.