Pattern looks improved for possible KU event 2/18-2/25 time range

[earthlight]

P001 actually phases in the northern stream to the point where it has a closed 500mb low over the Mid Atlantic that moves underneath the area. That would be the best case scenario possible in this upper air pattern.

[blizzardof09]

If there is any EASTERLY component to this keep in mind the Bouy`s around NYC are running 10 degrees above normal this Feb .

so will need this to jog east , have 4 days to sort it .

I think it has a good chance of doing that tham cutting close to the coast like that. Also im not really calling this a shift to a big hit for us until i see what euro shows in a bit when it comes out. Cautiously excited man

[PB GFI]

I think it has a good chance of doing that tham cutting close to the coast like that. Also im not really calling this a shift to a big hit for us until i see what euro shows in a bit when it comes out. Cautiously excited man

yeh i hear ya man

[earthlight]

Euro already not enthused with the northern stream at 42 hr. GFS has a shortwave trough moving much farther west through Montana. Euro not liking it.

[bluewave]

Lows tracking over ORF are usually warm for us here. The exceptions are when the H5 low closes off overhead

like we had back on Christmas 2002. The GFS doesn't move to close off the UL until it's past our area. You'll

need to see the Euro close off earlier or be east of ORF today to have some hope of a colder solution for our area.

[earthlight]

Big northern stream height falls over the Intl border at 60...if it's gonna pull it up the coast, it's gonna do it differently than the GFS. Lots of confluence over the Northeast.

[bass28]

Big northern stream height falls over the Intl border at 60...if it's gonna pull it up the coast, it's gonna do it differently than the GFS. Lots of confluence over the Northeast.

On my phone but "snowman"

[jm1220]

Lows tracking over ORF are usually warm for us here. The exceptions are when the H5 low closes off overhead

like we had back on Christmas 2002. The GFS doesn't move to close off the UL until it's past our area. You'll

need to see the Euro close off earlier or be east of ORF today to have some hope of a colder solution for our area.

It's hard for me to think of a time when we (on the coast) had a favorable outcome after a storm tracked over SE VA. Those tracks favor the Poconos, Catskills, and well inland areas. In State College, that's noted as a big time snow track. We would need the low to close off as you said very fast and track the storm ENE. Or develop a massive comma feature like X-mas 2002, and even that was a huge product of luck with that backlashing, after we had thunder/lightning and heavy rain all day.

[tornadojay]

P001 actually phases in the northern stream to the point where it has a closed 500mb low over the Mid Atlantic that moves underneath the area. That would be the best case scenario possible in this upper air pattern.

500 mb closed low would definitely be the best case scenario... no doubt about it.. If you take the operational GFS for what it's worth, although it's not closed, the positioning of the vort max at about the 102-105 hour time frame is about as perfect as you can get in setting up good deformation type snows... not to mention, there is strong thermal advection as well. Here's one of the key things to watch at the 850 mb level..... perpindicular isotherms and isotachs at high speeds.. and also little temperature change in a given area over time. That shows intense forcing... the placement of the 850 low is a lttle close for comfort, but all in all, pretty good.

Soundings show a classic, strong low level veering pattern and a strong isothermal level.

[earthlight]

Looks like pretty poor timing if we don't get the phase that the GFS shows...the trough swings through the Northeast and the mid level flow is very bad.

[Kaner587]

Looks like pretty poor timing if we don't get the phase that the GFS shows...the trough swings through the Northeast and the mid level flow is very bad.

which actually explains why we have OTS by hundreds of miles and coastal runner solutions at play here

[earthlight]

Will be offshore again...very poor timing. Third or fourth run in a row that the Euro has showed this general solution

[MJO812]

Will be offshore again...very poor timing. Third or fourth run in a row that the Euro has showed this general solution

GFS vs Euro. GFS has been better than the Euro this winter so maybe it is on to something. The ensembles do kind of agree with the op. Still early yet and anything can happen.

[earthlight]

The Ukie looks like the Gfs with this energy over the International Border at 48 hr. That is the feature to watch. If it comes in like this -- there is a very good chance of the upper level flow becoming more favorable for a surface low to track just off the coast. The Euro has this feature much more progressive even at 42-48 hr.

http://www.meteo.psu.edu/~gadomski/UKMET_12z/f48.gif

[bluewave]

GFS vs Euro. GFS has been better than the Euro this winter so maybe it is on to something. The ensembles do kind of agree with the op. Still early yet and anything can happen.

You would rather the EURO be right then correct a little further north next few days as GFS would be a rainstorm here at the coast.

[earthlight]

For comparative purposes...the Ukie and GFS have the northern stream trough I alluded to above over Montana and the Intl border at 48 hr...hanging back and swinging south/southeast.

At that same time the 12z Euro has the trough axis Eastern South Dakota and moving into Iowa.

[MJO812]

You would rather the EURO be right then correct a little further north next few days as GFS would be a rainstorm here at the coast.

I rather have the GEFS be right. All of them show a nice hit.

[jm1220]

I rather have the GEFS be right. All of them show a nice hit.

Some of those GFS ensembles are nice hits around here, but we need the GFS P track to be 75 miles or so east. As is, it's almost definitely rain on the coast. Snow not far inland. But if anything, we need just about perfect conditions due to the confluence over the NE for a hugger track to happen.

[earthlight]

Here's the feature just for an easier visualization. The smaller circle is where the Euro has the trough axis at the same time. Faster and more progressive...which subsequently keep the flow over the Eastern US very zonal as it moves east. We would want this feature to be farther west like the GFS and Ukie if we want a significant storm off the coast.

[mattinpa]

For comparative purposes...the Ukie and GFS have the northern stream trough I alluded to above over Montana and the Intl border at 48 hr...hanging back and swinging south/southeast.

At that same time the 12z Euro has the trough axis Eastern South Dakota and moving into Iowa.

Is it more north than 0z? Hearing in the MA forum that it is stronger and gets precip to DE.

[Porsche]

996 just off NC outer banks at 108.. a good bit west of 0z now, maybe 100 mi? not helping dc area much. far se va all .50+

[bluewave]

I rather have the GEFS be right. All of them show a nice hit.

I would like to see a suppressed solution today as the models still have more time to tick north later on.

[blizzardof09]

Well given that the gfs has been better than the euro this year has me comfortable even the gfs has support for its solutions, though i highly doubt it gets that close to the coast. Whats troubling though is the euro showing this solution in consecutive runs. However we are still outside of 96 hour window and things are gonna change.

[SBUWX23]

The GFS may be good this winter, but when was the last time this winter we had this many shortwaves and this many pieces of energy to model to get to a solution. Its something to keep in mind

Well given that the gfs has been better than the euro this year has me comfortable even the gfs has support for its solutions, though i highly doubt it gets that close to the coast. Whats troubling though is the euro showing this solution in consecutive runs. However we are still outside of 96 hour window and things are gonna change.

[bluewave]

Our best hope is a compromise over the next few runs that works out colder than the GFS.

[jm1220]

Our best hope is a compromise over the next few runs...

Yep. It pretty much comes down to the difference in speeds with that Northern Plains wave. Faster=suppressed flow and and a flat storm. Slower=flow buckles and storm has room to ride north up the coast. If the kicker could be just a little quicker in that case, it's a snowier solution and we don't have to worry about major issues with rain.

[blizzardof09]

The GFS may be good this winter, but when was the last time this winter we had this many shortwaves and this many pieces of energy to model to get to a solution. Its something to keep in mind

I dont think any making these inconsistencies even more evident and the flow being fast isnt helping things. I dont think we have to worry about an inland solution though because of that. We'll see where were at 48 hours from now to really see what transpires

[Rjay]

HPC

...SHORTWAVE TROUGH ENTERING THE PLAINS/MIDWEST FRI-SAT...

PREFERENCE: ECMWF

THE GFS APPEARS TO HAVE WORSE INITIALIZATION OF THE TROUGH'S

PLACEMENT OVER BRITISH COLUMBIA AND NUNAVUT THIS MORNING COMPARED

TO THE NAM/ECMWF. MEANWHILE...THE GFS IS MOST AGGRESSIVE IN

ALLOWING AN UPSTREAM PERTURBATION CURRENTLY OVER THE PACIFIC TO

CUT THROUGH THE SHORTWAVE RIDGE OVER THE CANADIAN ROCKIES ON

THURSDAY...WHICH THEN PHASES WITH THE NORTHERN STREAM AND SLOWS

THE ENTIRE GFS SOLUTION. THE COMBINATION OF WORSE INITIALIZATION

AND QUESTIONABLE AND EVEN SUSPICIOUS PHASING OF THE SEPARATE

STREAMS IS SUFFICIENT TO DISCARD THE GFS PARTICULARLY LATE IN THE

PERIOD. AMONG THE REMAINING SOLUTIONS...THE NAM BECOMES SLIGHTLY

FASTER THAN THE CANADIAN/ECMWF...WHILE THE UKMET IS SLOW AND

AMPLIFIED...WITH ITS GREATER AMPLIFICATION POSSIBLY AN INDICATION

OF ITS STRONG BIAS AT LATER TIME FRAMES. THUS...THE UKMET IS

DISCOUNTED. MEANWHILE...THE NAM...WHILE PLAUSIBLE...IS CONSIDERED

LESS LIKELY THAN THE ECMWF DUE TO ITS NARROWER DATA ASSIMILATION

WINDOW AND ULTIMATELY QUESTIONABLE INITIALIZATION PARTICULARLY AT

THE HIGHER LATITUDES.

CONFIDENCE: LESS THAN AVERAGE

...SHORTWAVE TROUGH OVER THE INTERMOUNTAIN WEST...

PREFERENCE: BEFORE 12Z FRI...NAM OR ECMWF

AFTER 12Z FRI...ECMWF

THE NAM BECOMES SLOWER AND REMAINS STRONGER...WHILE THE GFS

BECOMES MUCH FASTER LATER IN THE PERIOD COMPARED TO THE ECMWF

RESPECTIVELY...DUE IN LARGE PART TO DIFFERING DEGREES OF

INTERACTION WITH A SHORTWAVE TROUGH CROSSING TO ITS NORTH...WITH

THE GFS ACTUALLY PHASING WITH THE NORTHERN STREAM. DUE TO REASONS

DESCRIBED IN THE SYSTEM SECTION ABOVE...BOTH THE NAM AND GFS ARE

DISCOUNTED AFTER REACHING MEXICO...WITH A PREFERENCE TOWARD THE

ECMWF.

[BL03]

Euro is really speeding the southern stream.... reasonable given the pacific fast flow. Years (winters) like these you have to think how the pattern has treated this region and it hasn't been too good.

[Kaner587]

Euro is really speeding the southern stream.... reasonable given the pacific fast flow. Years (winters) like these you have to think how the pattern has treated this region and it hasn't been too good.

true but if it had a similar evolution of the northern stream disturbance that the UKMET/GFS had then it likely wouldn't have been such a swing and a miss.