February Mid/long Range Winter Discussion

[griteater]

Gfs continues to amplify the backside of the trough more than running the front energy through the lakes. This should continue to correct towards its ensembles and other models.

Yep, that's helping to hold the sfc high and damming in longer

[rduwx]

12z cmc very similar to the 12z gfs.  It looks to be a little warmer on the back end.

[griteater]

definitely concerning. Wpc tossed the ukmet solution on their morning update.

We'll have to see where the Euro goes....00z Euro Op was a lean more to the amped camp, Euro Para was a lean more to the flatter camp

[griteater]

Canadian has basically had the same solution for the last 4 runs....but it's been consistent, but wrong, plenty of times

[wncsnow]

Isn't the UKMET a little phase happy? This will take a few days to resolve. much like most of our wintry weather setups. Tough forecast for sure 

[Lookout]

WxSouth / Robert spoke of a pseudo / mesoscale high that remains in NW NC and another in C PA after the main high scoots out. Says that this may cause CAD and cold to remain during most of the duration of this storm. Talking about DP being extremely low and hard to overcome to warmth, and this type of system generally arrives quite earlier than modeled. But does say, of course, too early to tell, but is his thinking ATM. This is a pay sight, so did not want to C&P, but thought it was OK just to throw a couple of his thoughts to the forum.

He mirrors my thoughts here..as the 12z gfs looks very promising for meso high formation. Besides the obvious reasons i like the gfs has precip spreading eastward across the carolinas early/first which would only serve to promote such a feature due to the timing of evap cooling. Due to the initially very cold temps and even lower wet bulbs at the start combined with what is likely underestimated pressures which enhances easterly or ne flow...any warming the gfs is showing is almost for sure overdone and too fast.

[Brick Tamland]

I guess we have the GFS, CMC, and Euro para with similar solutions. Hope we continue to see things trend to those three. I think it is a big positive having the Euro para on our side since it has been really accurate.

[SnowNiner]

Wonder why the precip seems so suppressed when the low forms in the gulf?  Seems like there'd be more moisture into  W NC at this point...low just too weak?

 

[cmichweather]

Wonder why the precip seems so suppressed when the low forms in the gulf?  Seems like there'd be more moisture into  W NC at this point...low just too weak?

 

The trough is still positively tilted so you don't get precip developing well north and west of the low. 

[buckeyefan1]

12z GFS Bufkit for cae says it starts at 32.8 and ends at 38.2 with 1.59" of rain     

[burrel2]

He mirrors my thoughts here..as the 12z gfs looks very promising for meso high formation. Besides the obvious reasons i like the gfs has precip spreading eastward across the carolinas early/first which would only serve to promote such a feature due to the timing of evap cooling. Due to the initially very cold temps and even lower wet bulbs at the start combined with what is likely underestimated pressures which enhances easterly or ne flow...any warming the gfs is showing is almost for sure overdone and too fast.

 

CMC really goes to town with the meso-high. You can see the finger of high pressure stacked up against the back side of the app's here.

[NEGa]

He mirrors my thoughts here..as the 12z gfs looks very promising for meso high formation. Besides the obvious reasons i like the gfs has precip spreading eastward across the carolinas early/first which would only serve to promote such a feature due to the timing of evap cooling. Due to the initially very cold temps and even lower wet bulbs at the start combined with what is likely underestimated pressures which enhances easterly or ne flow...any warming the gfs is showing is almost for sure overdone and too fast.

 

the set-up, at least, looks fairly promising...enough to keep my interest for sure.  we have a very cold airmass this weekend with low dewpoints setting the stage.  as long as we can get some precip in fast enough hopefully we can get the cold air to stay in place, at least for a majority of the event.  while it can, and does, snow or ice after warm temps, having a good, cold couple of days to set the stage is always a plus. 

 

lets just hope this doesnt turn into a cutter lol

[SnowNiner]

The trough is still positively tilted so you don't get precip developing well north and west of the low. 

 

Thanks!

 

Of course to get more precip then, we'd need a negative tilt stronger storm, which would drive warmer air in and bring rain.  I'll just move on now....lol. 

[franklin NCwx]

Thanks!

Of course to get more precip then, we'd need a negative tilt stronger storm, which would drive warmer air in and bring rain. I'll just move on now....lol.

the gfs puts too much emphasis on the front running wave and keeps the trough too positively tilted. Its slowly correcting out of its usual bias of doing that and putting more on the backside of the trough. It will correct to a more amplified storm in future runs. How much more I have no idea.

[toxictwister00]

WPC (although this was posted before the 12z UKMET came out) don't seem to be giving any weight to it. 

 

HAVE NO CONCERN WITH THE DAY3-4 DETAILS EMBEDDED WITHIN THE LEAD
PACIFIC WAVE ENERGY AND SOLUTIONS THAT ALLOW THE MAJORITY OF THE
VORTICITY TO SHEAR EASTWARD --- AND EAST OF THE CONTINENTAL DIVIDE
(ACROSS THE ENTIRE STRETCH OF THE MISSOURI AND PLATTE RIVER
VALLEYS). THE 10/00Z UKMET REALLY IS THE ONLY SOLUTION THAT
CONTINUES TO PROJECT A 'WEST OF THE DIVIDE' STORM TRACK SOLUTION
--- AND IS A SOUTHERN OUTLIER OVER THE FOUR CORNERS FOR A SECOND
00Z CYCLE IN A ROW. BECAUSE IT IS A 'FOUR CORNERS' SOLUTION --- IT
WILL CERTAINTY MAINTAIN A MORE VOLATILE AND AGGRESSIVE SOLUTION
ACROSS THE SOUTHERN PLAINS. THE EVOLVING FLOW PATTERN DOWNSTREAM
SEEMS TO 'DEBUNK' THE AGGRESSIVE UKMET APPROACH MID-PERIOD.

 

DO HAVE TO GO WITH A 10/00Z ECENS...NAEFS AND GEFS BLEND (50/30/20
WEIGHTING) AFTER 15/00Z DUE TO THE DETERMINISTIC VARIANCE AT
500MB...SURFACE AND ALIGNMENTS OF THE PRECIPITATION DISTRIBUTIONS
ALONG AND EAST OF THE MISSISSIPPI/OHIO VALLEYS.

 

THE 10/00Z DETERMINISTIC GFS/CANADIAN

AND ECMWF SEEMED TO BE IN DECENT AGREEMENT (INVOF THE OZARKS)
UNTIL 15/00Z BEFORE THE 10/00Z GFS ALLOWS A NORTHERN STREAM
SHORTWAVE TO BECOME THE MORE DOMINANT SYNOPTIC-SCALE ENTITY IN THE
FLOW. THE RESULT BEING...MORE OF A POSITIVE-TILT TROUGH AXIS
(ALBEIT A BRIEF ONE) ALONG THE EAST COAST BY 17/00Z. THIS
SOLUTION...BUT MORE SO---THE 10/00Z UKMET SEEM TO BE THE LEAST
LIKELY DETERMINISTIC SCENARIOS.

 

THAT SAID...THE 10/00Z DETERMINISTIC CANADIAN/ECMWF...10/00Z

GFS-PARALLEL AND 10/06Z DETERMINISTIC GFS (OPERATIONAL RUN) SEEM
TO BE THE BETTER REPRESENTATIONS HEADING INTO DAY 6. GIVEN THE
10/00Z ENSEMBLE GUIDANCE SCENARIO --- AND THEIR PROJECTIONS FOR
MID-LEVEL TROUGH AMPLITUDE EXITING THE EASTERN SEABOARD --- THE
10/00Z AND 10/06Z CYCLES (DETERMINISTIC VIEWPOINT) BEYOND DAY 5
AND HEADING INTO DAY 6 SEEMED TO BE "FAR FROM A PERFECT PROG SNAP
SHOT".

 

http://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=pmdepd

[SN_Lover]

I'm not a fan of the setup. Departing high, degrading CAD, and low to the NE. This looks like a zipper low more than a Miller A cyclogenesis now. We are several days away, so things can change.  

[SnowGoose69]

I'm not a fan of the setup. Departing high, degrading CAD, and low to the NE. This looks like a zipper low more than a Miller A cyclogenesis now. We are several days away, so things can change.

This is more likely to turn into a glorified FROPA I think than it is what the UKMET shows

[SnowNiner]

the gfs puts too much emphasis on the front running wave and keeps the trough too positively tilted. Its slowly correcting out of its usual bias of doing that and putting more on the backside of the trough. It will correct to a more amplified storm in future runs. How much more I have no idea.

 

Thanks Franklin.  Seems like a very thin balanced line needs to be walked here between a little stronger storm, but not too much.  Right now, I'm rooting for the canadian...

[griteater]

00z Euro Para Ensemble is out and it's an improvement from its previous run.  Flatter wave, NE vortex and sfc high a little slower to retreat, colder

[franklin NCwx]

This is more likely to turn into a glorified FROPA I think than it is what the UKMET shows

you think so? Ensemble means continue to imply a decent. system in the coast.

[franklin NCwx]

Thanks Franklin. Seems like a very thin balanced line needs to be walked here between a little stronger storm, but not too much. Right now, I'm rooting for the canadian...

There always is. That's why small changes at 5h can have big differences at the surface.

[Solak]

12z GFS --- crippling ice for RDU --- 3/4"

 

http://coolwx.com/cgi-bin/getbufr.cgi?region=NC&stn=KRDU&model=gfs&time=current&field=prec

[Brick Tamland]

12z GFS --- crippling ice for RDU --- 3/4"

 

http://coolwx.com/cgi-bin/getbufr.cgi?region=NC&stn=KRDU&model=gfs&time=current&field=prec

 

3 inches of snow, too.

[FallsLake]

12z GFS --- crippling ice for RDU --- 3/4"

 

http://coolwx.com/cgi-bin/getbufr.cgi?region=NC&stn=KRDU&model=gfs&time=current&field=prec

That would be especially bad because of the initial very cold surface temps. Basically all that freezing rain would stick straight to the roads.

 

edit: I bet there would be a lot of sleet mixed in to drop that total some.

[SN_Lover]

This is more likely to turn into a glorified FROPA I think than it is what the UKMET shows

Yup, only a week low if anything accompanying the front with the dom low being to the North. Ens members have been persistently projecting this also. 

[franklin NCwx]

Yup, only a week low if anything accompanying the front with the dom low being to the North. Ens members have been persistently projecting this also.

What ensemble members?

[franklin NCwx]

Thanks Franklin. Seems like a very thin balanced line needs to be walked here between a little stronger storm, but not too much. Right now, I'm rooting for the canadian...

12z cmc went to this with less backside energy. So it's less amped and warmer.

[franklin NCwx]

Gfs ensembles

[SN_Lover]

Gfs ensembles

efs_snow_ens_east_30.pnggefs_z500a_noram_25.png

Me and snowgoose are talking about the synoptic setup as a whole. I can't speak for snowgoose but my analysis is not based off of raw snow maps. 

[Tony Sisk]

I'm not a fan of the setup. Departing high, degrading CAD, and low to the NE. This looks like a zipper low more than a Miller A cyclogenesis now. We are several days away, so things can change.  

I'm in agreement with you. With the angle of the NE low, I'm not sure there is enough tilt to get the moisture needed, south and east of the mountains. And if it does, does that SE moisture erode CAD even quicker.