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

[Absolute Humidity]

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.

"THE GFS APPEARS TO HAVE WORSE INITIALIZATION" Kinda reminds of Boxing Day HPC disco 36h before the 1st flakes when the GFS's blizzard spanked down the ECMWF's OTS solutions.

[earthlight]

SREF mean at 15z has trended towards much more northern stream interaction when compared to the last two runs. End of the run obviously, so little confidence, but worth noting.

[blizzardof09]

SREF mean at 15z has trended towards much more northern stream interaction when compared to the last two runs. End of the run obviously, so little confidence, but worth noting.

Overall john take into account the model runs so far today we've seen somewhat of a more northern stream interaction making the storm jog every so slightly north

[RUNNAWAYICEBERG]

it would be nice to see tonights euro run trend to a more slower northern stream, not scooting it so quickly to the E but having it dig to the S instead. we dont necessarily need it to show a complete phase bomb, just a trend towards the GFS will work... that would deff raise the interest level that the gfs is not off its rockers. also, im not sure this is your typical big system where we need the GFS to be S and E 3/4 days away where it then starts the NW trend. those that are worried the gfs is too NW already shouldnt imo. if anything, it is ironic you have the euro and gfs basically flip flopped from their usually positions this far out.

[Allsnow]

12z euro ensembles def better than 00z ensemble mean. North, amped, and better digging.

[Kaner587]

Snowman (on iPhone lol)

[Allsnow]

I can't see QPF on the ensembles unfortunately. But definitely much much stronger than 00z ensemble run and a deeper troiugh that's held back a bit.

[ag3]

The euro ensemble mean has very little precip making it to NYC though. Yes, they are more north and amped then the operational and last night's ensemble, but not as good as yesterday's 12 ensemble mean.

[Allsnow]

They definitely are better looking than the op, and rather significantyl so. Still not good enough to get QPF into SNE from what I can tell...but it's better than the op. Still a very large spread even at hr 90, at 500mb.

Yeah agreed. Better than op and better than 00z ensemble. Nice to see a noticeable trend NW.

Euro Ensemble Mean is ~ 100 mi. north of the OP at 108-114... and 120 is NW by ~ 150. Mean takes the storm on a more SW to NE trajectory vs. the OP which shunts it East (while developing an eyewall on the western edge of the LP) ... this is a positive development.

[earthlight]

NAM farther west with the shortwave north of Montana at 30 hours. Height field closely resembles the GFS. But the flow to the south of that doesn't look quite as favorable to get it as far west as the GFS shows. We'll see.

[Allsnow]

Ok, so about 5-8 members are solid hits for the East Coast. So, the ensemble mean is spitting out 2-4 for PHL, but I think it is a boom and bust mean. The median is probably 0.

Huge red flag....Idc what 4dvar text ag3

[Snow_Miser]

NAM farther west with the shortwave north of Montana at 30 hours. Height field closely resembles the GFS. But the flow to the south of that doesn't look quite as favorable to get it as far west as the GFS shows. We'll see.

Well if it hypothetically would not come as far west as the GFS, then that would be a good thing, considering the GFS was a rainstorm for us, and it was WAY amped.

We need the GFS to deamplify and the ECMWF to amplify, although the ECMWF appears to be doing that from what trends I've seen from today's 00z Operational and ENS, compared to today's 12z Operational and Ensembles.

[ag3]

Huge red flag....Idc what 4dvar text ag3

He did not text me anything. I have access to the mean precip.

But the spaghettis do look very impressive.; just saw those also.

[supermeh]

He did not text me anything. I have access to the mean precip.

But the spaghettis do look very impressive.; just saw those also.

The OP on those spaghettis is pretty far south compared to everything else.

[ag3]

The OP on those spaghettis is pretty far south compared to everything else.

The most impressive thing on the spaghettis is that the majority of the members are clustered well north of the operational and also the strength of the individual members is quite impressive.

[bluewave]

The OP on those spaghettis is pretty far south compared to everything else.

That would be good news for us. Hopefully the GFS moves a little further south and east the next few days.

[blizzardof09]

He did not text me anything. I have access to the mean precip.

But the spaghettis do look very impressive.; just saw those also.

It was a step in the right direction today though ag3. I mean there wasnt a real swing and miss run yet like not even close to a phase or anything

[bluewave]

Notice the lower ENS mean heights over the Ohio Valley.

[blizzardof09]

Notice the lower ENS mean heights over the Ohio Valley.

Good thing i take it? Im trying to understand it man

[Ericjcrash]

Notice the lower ENS mean heights over the Ohio Valley.

Much better then the OP

[bluewave]

Good thing i take it? Im trying to understand it man

Much better then the OP

Yeah, that would support a surface low coming further up the coast.

Hopefully the OP Euro doesn't get as far NW as the GFS did next

few runs. Just east of ORF to east of Cape Cod would be great

for us since the winds would stay more NE than ENE.

[psv88]

Notice the lower ENS mean heights over the Ohio Valley.

540 thickness pretty far north...

[NYCSuburbs]

Is it even a possible thing to not have a complicated forecast this winter with the bigger storms? Having the GFS show a borderline rainstorm and the CMC way to the south certainly doesn't help

This set up is more favorable than the other ones this winter and certainly has the potential to produce something bigger, but the pattern is still generally progressive and the western ridging isn't very supportive, and with the pattern and trends so far, I'd rather see a better consensus emerge among the models supporting either the southern slider or big northern storm scenario before going with one of them with higher confidence.

[earthlight]

540 thickness pretty far north...

That's the 540dm height line at 500 hPa..not the 1000-500mb thickness.

[bluewave]

Is it even a possible thing to not have a complicated forecast this winter with the bigger storms? Having the GFS show a borderline rainstorm and the CMC way to the south certainly doesn't help

This set up is more favorable than the other ones this winter and certainly has the potential to produce something bigger, but the pattern is still generally progressive and the western ridging isn't very supportive, and with the pattern and trends so far, I'd rather see a better consensus emerge among the models supporting either the southern slider or big northern storm scenario before going with one of them with higher confidence.

At least the models slowed down that kicker coming into the West Coast today but we still have to get through

Thursday PM/Friday AM runs to get within the 60 hr window. I am just hoping this does not hug the coast.

[SBUWX23]

Thats geopotential height, not thickness on those maps.

540 thickness pretty far north...

[NYCSuburbs]

At least the models slowed down that kicker coming into the West Coast today but we still have to get through

Thursday PM/Friday AM runs to get within the 60 hr window. I am just hoping this does not hug the coast.

Some of the latest changes on the models have been favorable, but there's still issues with the phasing. We're probably going to have to get the right amount of phasing as this isn't an ideal set up, too much phasing would take this to our west or make it too warm, and less phasing would keep it to our south.

[psv88]

Thats geopotential height, not thickness on those maps.

My bad.

[Isotherm]

18z NAM looks like it would probably be a big hit for the southern Mid atlantic, with a ton of confluence across sern Canada and New England, W-E mid level flow, and the 50-50 pretty far SW. I tell you though - ton of moisture with this system. First time all season we finally have a juiced up STJ short wave with decent antecedent synoptics over SE Canada/Northeast.

[bluewave]

Some of the latest changes on the models have been favorable, but there's still issues with the phasing. We're probably going to have to get the right amount of phasing as this isn't an ideal set up, too much phasing would take this to our west or make it too warm, and less phasing would keep it to our south.

It's a least nice to see the pattern finally throwing the models a curve ball in relation to run to run swings.

We'll need a few more days to know that exact track though.