December 9/10 Storm

[Bob Chill]

6 minutes ago, nj2va said:

They’ve been bouncing around like a fish out of water...6”, 2”, 1”, 7”, 0”, 2”, 1” and so on.  The ensembles seem less useful this go around for some reason.

18z is unanimous for the first time. Completely lasered in on the op. I don't think the ens have been bad with this event. They have favored the nc/sva hit for many runs. The spread kept us hooked because there were enough good ones in the mix but overall the southern solution was always the majority. 

I do think it's still possible for a shift north but the idea is fading every six hours now unfortunately. 

[nj2va]

4 minutes ago, Bob Chill said:

18z is unanimous for the first time. Completely lasered in on the op. I don't think the ens have been bad with this event. They have favored the nc/sva hit for many runs. The spread kept us hooked because there were enough good ones in the mix but overall the southern solution was always the majority. 

I do think it's still possible for a shift north but the idea is fading every six hours now unfortunately. 

Oh they (OP and ENS) have favored SW VA/W NC for days but they’ve been bouncing around up here (similar to the OPs)...maybe that’s due to DC/NVA being on the northern fringe so any jog will have a significant impact here?  I don’t remember an event where the snowfall means jumped from run to run like it has with this event.  Though honestly, I don’t have a laser precise memory like some here where they remember every event like clockwork.  

We’re on life support but I still think this comes north some.  

[aldie 22]

Dear lord I hope the next threat suddenly appears the day before it hits

[luckyamaha]

Doug Kammerer is live on FB explaining.

[poolz1]

If we all lived in ROA we would highly impressed with model consistency.  Sure there have been a few models here and there that spit out hope in the past 48 hours but this is a big storm and models have done a pretty good job.  We are about out of luck, imo.  I understand that weather can do what it wants and i'll continue to watch every run with hopes for a hail mary but the writing is on the wall....

If 0z gives no obvious shift in the features needed....I'm out....until Friday happy hour!

[frd]

Mentioned this earlier about the role of the PV. Looking at this view you can certainly see how it crushes the storm from making a significant move North.

 

 

[cae]

17 minutes ago, nj2va said:

Oh they (OP and ENS) have favored SW VA/W NC for days but they’ve been bouncing around up here (similar to the OPs)...maybe that’s due to DC/NVA being on the northern fringe so any jog will have a significant impact here?  I don’t remember an event where the snowfall means jumped from run to run like it has with this event.

The GEFS means can bounce around quite a bit due to their underdispersion.  We saw it several times last year too.  I think there's supposed to be a fix for this in the FV3 ensemble, but that isn't expected to be out until early 2020.  Hopefully by this time next season we'll all be complaining about the new para-GEFS. 

[nj2va]

Welp, its the NAM but through 63, the sw ss is stronger resulting in heigher heights in front.  Confluence in NE is north of 18z.  We’ve got nothing to lose so we might as well analyze the NAM.  

[yoda]

2 minutes ago, nj2va said:

Welp, its the NAM but through 63, the sw ss is stronger resulting in heigher heights in front.  Confluence in NE is north of 18z.  We’ve got nothing to lose so we might as well analyze the NAM.  

There is a closed h5 low at 00z 63 that was open at 18z 69 FWIW in the Texas panhandle 

[clskinsfan]

The NAM is closed at 500 over TX at hour 57. But there is a brick wall just waiting for it over central PA. 

[kurtstack]

this is not necessarily scientific but i was in altoona, pa for the march storm and for the november storm and both times models had em on the northern fringe - forecasts 24 hours out were for a couple inches of snow - in both cases they ended up getting 10”+.  forecast confidence for the fringe areas of storms is mighty low - its probably the most difficult area for forecasters with any storm.

[nj2va]

5 minutes ago, clskinsfan said:

The NAM is closed at 500 over TX at hour 57. But there is a brick wall just waiting for it over central PA. 

You’re telling me.  By 75, its pressing down a touch more than 18z.

ETA:  it’s like the giant middle finger stop sign from the NS.  

[yoda]

The h5 low actually moves NE from hr 81 to 84 lol

[nj2va]

7 minutes ago, losetoa6 said:

Small but positive changes at h5 through 63. Spoke too soon .Confluence reared its ugliness again at 75

It looked better early but the wheels fell off the train towards the end.  The confluence does not want to give up.

[psuhoffman]

9 minutes ago, losetoa6 said:

Small but positive changes at h5 through 63

I dunno that looks like a brick wall still in its way. Look at the h5 from previous stj storms. We need that confluence at least 100 miles north of where it is. And that is trending south not north. 

[psuhoffman]

Compare the nam at 84 with the ggem run from this morning. Not even close. In any way. 

[LP08]

ICON is south of 18z...not much precip into VA

[luckyamaha]

Even less of a phase if any at hr 78 on the NAM compared to the 18z run. 

[psuhoffman]

The nam is actually south of the gfs even. Wasn't a good run imo. 

[Ji]

00z runs are going to be off the chains ugly tonight. Icon looks like its going to move south the 200 miles it went North with at 18z

[psuhoffman]

I think there is a trend now. It's just not the trend we wanted. I still think this will do the typical adjustment north the last 48 hours. But it might not matter now. 

[SnowGolfBro]

Sometimes the confluence is overdone on the models. I think that’s the wildcard but it’s getting less wild as time goes by

[psuhoffman]

3 minutes ago, losetoa6 said:

Up to 63 confluence looked a bit better but 75 the hammer dropped

You could see that NS vort coming though and how it was gonna be in the way. 

[Ji]

3 minutes ago, psuhoffman said:

I think there is a trend now. It's just not the trend we wanted. I still think this will do the typical adjustment north the last 48 hours. But it might not matter now. 

psu....if i had to count 10 storms that weve tracked recently that need a positive trend...i would say 9 of those have failed. We can never get the right trend and often they go opposite of what we want. We would of been happy today just maintain status quo

[psuhoffman]

Just now, Ji said:

psu....if i had to count 10 storms that weve tracked recently that need a positive trend...i would say 9 of those have failed. We can never get the right trend and often they go opposite of what we want. We would of been happy today just maintain status quo

Yea but that's just normal. We were on a heater from 2014-16 where we hit an unusual percentage of threats. Since we have been below typical maybe. It evens out. Even in great years they don't all hit. Did you see the euro seasonal. We will have lots of threats this year. And hopefully some will come without a NS death pinwheel off New England to suppress them. I'm banking this won't be the only time the stj throws something like this at us and some will hit. 

[Ji]

Just now, psuhoffman said:

Yea but that's just normal. We were on a heater from 2014-16 where we hit an unusual percentage of threats. Since we have been below typical maybe. It evens out. Even in great years they don't all hit. Did you see the euro seasonal. We will have lots of threats this year. And hopefully some will come without a NS death pinwheel off New England to suppress them. I'm banking this won't be the only time the stj throws something like this at us and some will hit. 

i know but to toss a 1-2 foot snowstorm and hope another comes along is just hard to phatom. Especially when places that shouldnt get snow are taking ours

[SnowGolfBro]

5 minutes ago, Ji said:

i know but to toss a 1-2 foot snowstorm and hope another comes along is just hard to phatom. Especially when places that shouldnt get snow are taking ours

So far they are only looking at digital snow. If this does miss us to the South we are almost certainly going to be having radar hallucinations even though we know it’s out of reach.

[Ji]

Just now, SnowGolfBro said:

So far they are only looking at digital snow. If this does miss us to the South we are almost certainly going to be having radar hallucinations even though we know it’s out of reach.

i was banking on 3 HECS this season....losing this one is going to really my chances

[Roger Smith]

Your chances for a direct hit are one in four perhaps, but 50-50 for 2-4" near the northern fringes of the snow. Those aren't bad odds for first third of December.

Not a very easy set-up for models to resolve, one thing in favor of a storm would be warm SST values offshore, could force a last minute northeast jog and you'll catch at least some of this.

Best bet at this point is 2-5" DCA, but range of possible amounts trace to 15" so lots to play for here. 

[Maestrobjwa]

16 minutes ago, psuhoffman said:

Yea but that's just normal. We were on a heater from 2014-16 where we hit an unusual percentage of threats. Since we have been below typical maybe. It evens out. Even in great years they don't all hit. Did you see the euro seasonal. We will have lots of threats this year. And hopefully some will come without a NS death pinwheel off New England to suppress them. I'm banking this won't be the only time the stj throws something like this at us and some will hit. 

So you mean to tell me we can have something like that even if we are NOT in a nina? And tell me...this...awful entity and wrecker of snow hope that is looking to steal our snow this time...is this a feature where, at long range (like looking for good patterns on the weeklies and such) we can say "Ah, with this setup, NS suppression isn't likely"--Because I don't want to even look at another threat where this particular thing can happen...because it seems to be a pointless fight. (Right now, the mere mention of "northern stream" makes me cringe)