December 18-20 Talking Points - Part 2

[IsentropicLift]

looks like the NAM jumped towards the GFS on this run. What can we take from this? Lends confidence to the location of the PV. Still up for grabs... strength and location of the SW.

[Kaner587]

Agree...also even though the trough is further west than the 6z for this time frame, it is more positively tilted. Looks like a surrender to the Euro and its ensembles.

euro=no southern stream

NAM=southern stream

but because it shows a further east storm its a surrender to the euro...interesting

[RowanBrandon]

This storm won't happen, hate to talk like that, will still stay tuned in but not looking good at all.

Maybe not for west of I-95, but those east of I-95 still have skin in the game.

[Kaner587]

earthlight....300mb looks ridiculously improved at 84...might be too late for anyone but eastern coastal sections but its not a euro type solution

[Dsnowx53]

earthlight....300mb looks ridiculously improved at 84...might be too late for anyone but eastern coastal sections but its not a euro type solution

wow...you're right.

[ag3]

700rh and sims look pretty good at hour 84. I don't see anything close to euro.

[gkrangers]

weenies will now commence bridge jumping.

lets hope it rallies

The bridge jumping is terrible, tho more understood for people west of 95.

The NAM looks to me like it would be more than close enough to keep those nearer the coast in the game.

[IsentropicLift]

Assuming at 84hrs the trough is about to go negative we are in decent shape. The trough axis however looks to be a tad east of ideal.

[goombatommy]

NOAA updated their forecast + AFD:

Saturday Night: A chance of snow. Mostly cloudy, with a low around 23. Chance of precipitation is 30%.

Sunday: A chance of snow. Mostly cloudy, with a high near 35. Chance of precipitation is 40%.

AFD:

THE EVENTUAL OUTCOME OF LARGE LOW PRESSURE DEVELOPING SOUTH AND

EAST OF NEW ENGLAND SUNDAY AND MONDAY.

THE OPERATIONAL AND ENSEMBLE SUITE THAT WE ROUTINELY REVIEW HAVE

BEEN CYCLICALLY VARIABLE REGARDING WHETHER OR NOT A NEGATIVE TILT

TROUGH CAN CUT OFF SOON ENOUGH TO DEVELOP A SIZABLE COASTAL LOW WITH

SNOW AND WIND FOR OUR MID ATLANTIC COAST.

WE HAVE FOLLOWED THE CONSENSUS OF THE 12Z/15 NAEFS GGEM/GFS SOLN ..

BUT KNOWING THAT THE ONCE ROBUST ECMWF AND UKMET HAVE DEPARTED EAST

AND BENIGN FOR OUR AREA.

WE`RE TALKING 4 TO 5 DAYS FROM NOW. THOSE THAT HAVE PLANS FOR

SUNDAY ALONG THE COAST ESPECIALLY...SHOULD MONITOR FORECAST TRENDS

THE NEXT SEVERAL DAYS.

IF THIS SYSTEM MISSES US...THEN WE MIGHT NOT SEE MORE THAN A TENTH OF

AN INCH OF MELTED WATER EQUIVALENT IN MOST OR ALL OF OUR AREA

BETWEEN THE 13TH AND 22ND.

MAY ADD MORE DETAIL AROUND 5PM REGARDING PROBABILISTIC SCENARIOS.-- End Changed Discussion --

[ace0927]

earthlight....300mb looks ridiculously improved at 84...might be too late for anyone but eastern coastal sections but its not a euro type solution

how so? please explain- im not being facetious...want to learn....

[Kaner587]

theres also the 500mb set up up around 50/50 which looks like albeit late wants to break off which would allow nice negative tilting and amplifcation...if this happens 6 hrs earlier who knows. I wish I knew how to draw on those maps. Oh well maybe some one can show it graphically.

[Kaner587]

how so? please explain- im not being facetious...want to learn....

someone can explain the meteorology behind it but if you looks at the 300mb map there are 3 shades of blue, and at the last second the darkest blue is north of us and I believe that shows a connection has been made with the southern stream or something to that effect, and you want to be below and at the left corner of the highest winds or w/e those colors represent. someone help who actually knows whats going on lol

[goombatommy]

Yeah sorry, Im not gonna lie and say I totally understand what the models depict. Maybe just a gut feeling, maybe trying to avoid the let down of totally whiffing with this storm, sorry about the negativity, I'll just lurk and read these very informative posts.

I'm going to assume your from York, PA - judging by your username. As I've stated earlier, this was never intended to be a storm for us. Like Kaner said, anyone west of i95 just forget it - and it does look that way. I do have something to tell you - and that is, always cling on hope. Especially with winter storms - they can be unpredictable up until the ETA. Hell, the storm can take a 180 and clobber everyone north of DC - you never know, you just don't know until closer to and at ETA. I'm up in ABE - everyone has doubted we'll see anything but I'm clinging to a little hope we'll squeeze maybe and inch out of this. Better than nothing! =D Plus, we have the rest of the season to deal with.

And I think this is one of the longest posts I've ever written =/.

[am19psu]

someone can explain the meteorology behind it but if you looks at the 300mb map there are 3 shades of blue, and at the last second the darkest blue is north of us and I believe that shows a connection has been made with the southern stream or something to that effect, and you want to be below and at the left corner of the highest winds or w/e those colors represent. someone help who actually knows whats going on lol

You're describing jet streaks. In the right entrance and left exit of jet streaks, divergence aloft is enhanced. If you are still curious, we can go into the actual dynamics, but let's wait until after this event is over. Bottom line, the stronger the winds in a jet streak, the better divergence in the left front and right rear quadrants.

[A-L-E-X]

Have already done that ..the GFS has NADA to do with what i was trying to get across..

The point I am trying to get across is that the ECM is fallible just like any other model it is not till 48 hrs and under that it would be in its more efficient deadly range..

Well by that method, we shouldnt have a "lock" on this until Thursday night's runs. 

[earthlight]

You're describing jet streaks. In the right entrance and left exit of jet streaks, divergence aloft is enhanced. If you are still curious, we can go into the actual dynamics, but let's wait until after this event is over. Bottom line, the stronger the winds in a jet streak, the better divergence in the left front and right rear quadrants.

This. I personally like the jet streak positioning on the 12z run better especially with the s/w negatively tilted further west. There is some argument the PV could pull it back this run.

[Chris L]

You're describing jet streaks. In the right entrance and left exit of jet streaks, divergence aloft is enhanced. If you are still curious, we can go into the actual dynamics, but let's wait until after this event is over. Bottom line, the stronger the winds in a jet streak, the better divergence in the left front and right rear quadrants.

I was talking about this with another meteorologist,

stronger winds, better divergence and that will in turn create a stronger surface low?

[Kaner587]

You're describing jet streaks. In the right entrance and left exit of jet streaks, divergence aloft is enhanced. If you are still curious, we can go into the actual dynamics, but let's wait until after this event is over. Bottom line, the stronger the winds in a jet streak, the better divergence in the left front and right rear quadrants.

ya it seems I learn a new layer of the atmosphere every season LOL. First it was the surface, then 850 and 700, a couple years ago 500 and then last yr with all the major storms 300.

[Keith O]

Not looking good for NW Jersey either and seems to be the story of the past few years that areas S and E of here or far NE of here have cashed in. Does't seem to matter if Nino or Nina everything has found a way to miss, frustrating but what can you do. Not holding my breath on this one as cards on the table are not promising for MBY. Back to lurking....

I'm going to assume your from York, PA - judging by your username. As I've stated earlier, this was never intended to be a storm for us. Like Kaner said, anyone west of i95 just forget it - and it does look that way. I do have something to tell you - and that is, always cling on hope. Especially with winter storms - they can be unpredictable up until the ETA. Hell, the storm can take a 180 and clobber everyone north of DC - you never know, you just don't know until closer to and at ETA. I'm up in ABE - everyone has doubted we'll see anything but I'm clinging to a little hope we'll squeeze maybe and inch out of this. Better than nothing! =D Plus, we have the rest of the season to deal with.

And I think this is one of the longest posts I've ever written =/.

[Dsnowx53]

This. I personally like the jet streak positioning on the 12z run better especially with the s/w negatively tilted further west. There is some argument the PV could pull it back this run.

The 12z run was better IMO, but the 18z 300mb look was still okay.

[am19psu]

I was talking about this with another meteorologist,

stronger winds, better divergence and that will in turn create a stronger surface low?

All things being equal, more divergence aloft means deeper low pressure and more convergence at the surface.

[bluehens]

The 84 hr NAM maps look like everything gets going just a little too late. I would think this would end up further off shore but not Euro-esque. Probably a matter of 6-12 hrs earlier on the phase and we'd be in good shape.

The idea that keeps me hooked even though the Euro is so far OTS is that some of the mets I really respect here still like the way everything on it looks except for the strength of the southern stream s/w. There seems to be a lot of agreement that IF the s/w came in stronger then we'd be in business. I hope that happens tonight or tomorrow afternoon.

[Kaner587]

earthlight, am19psu et al if you look at the 500mb at 84hr doesn't it look close to splitting a piece of the PV around 50/50 which would allow for more amplification/negative tilting, esp if it occurs earlier?

[Dsnowx53]

The 12z run, though, had a much better jet streak on the left side of the base of the trough, so 12z was amplifying more, and earlier.

I think the 18z NAM would look similar to the 12z GFS, at best.

[ace0927]

You're describing jet streaks. In the right entrance and left exit of jet streaks, divergence aloft is enhanced. If you are still curious, we can go into the actual dynamics, but let's wait until after this event is over. Bottom line, the stronger the winds in a jet streak, the better divergence in the left front and right rear quadrants.

thank you.

left front? as in west of the trough?

[goombatommy]

Not looking good for NW Jersey either and seems to be the story of the past few years that areas S and E of here or far NE of here have cashed in. Does't seem to matter if Nino or Nina everything has found a way to miss, frustrating but what can you do. Not holding my breath on this one as cards on the table are not promising for MBY. Back to lurking....

I'm right across the river in Easton - literally less than 5 minutes from the NJ Border - I'm hoping to squeeze an inch out if that. But hey, there have been years in the past where we have ultimately been the predominant snow spots. Now its the south and east's turn to have some of it. We will get ours, and its not to say we will go this season without any accumulating snow, we will see some lol. Keep the faith!

[earthlight]

The 12z run, though, had a much better jet streak on the left side of the base of the trough, so 12z was amplifying more, and earlier.

I think the 18z NAM would look similar to the 12z GFS, at best.

At the very best, if you ask me. The DGEX will give us more insight, but I think it will end up east of the GFS and further east than the left side of the model envelope. It's just a little too late.

[IsentropicLift]

From Upton : Very well put in my opinion....sort of sums it all up

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN

CONNECTICUT...NORTHEAST NEW JERSEY AND SOUTHEAST NEW YORK.

.DAY ONE...THIS AFTERNOON AND TONIGHT.

HAZARDOUS WEATHER IS NOT EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY.

LOW PRESSURE WILL DEVELOP OFF THE MID ATLANTIC COAST BY SUNDAY

MORNING...AND IS CURRENTLY FORECAST TO TRACK INTO THE GULF OF

MAINE BY MONDAY MORNING. ON THIS TRACK...THERE IS THE POTENTIAL

FOR A SIGNIFICANT SNOWFALL ACROSS THE TRI-STATE FROM LATE

SATURDAY NIGHT INTO MONDAY MORNING. AT THIS TIME...IT APPEARS THE

BEST CHANCE OF SIGNIFICANT SNOW IS OVER EASTERN CONNECTICUT AND

LONG ISLAND. THERE IS STILL QUITE A BIT OF UNCERTAINTY ON THE

TRACK AND STRENGTH OF THE STORM...WITH THE POSSIBILITY EXISTING

THAT THE AREA WILL RECEIVE NO PRECIPITATION EARLY NEXT WEEK.

[Stormlover74]

Yeah but with the exception of last winter, which was a rarety, your area and north will almost always do better snowwise. It's not like we are talking about a climatological shift here

Not looking good for NW Jersey either and seems to be the story of the past few years that areas S and E of here or far NE of here have cashed in. Does't seem to matter if Nino or Nina everything has found a way to miss, frustrating but what can you do. Not holding my breath on this one as cards on the table are not promising for MBY. Back to lurking....

[_AR_]

I'm right across the river in Easton - literally less than 5 minutes from the NJ Border - I'm hoping to squeeze an inch out if that. But hey, there have been years in the past where we have ultimately been the predominant snow spots. Now its the south and east's turn to have some of it. We will get ours, and its not to say we will go this season without any accumulating snow, we will see some lol. Keep the faith!

12Z GFS ensemble member p001.

There's always one, I tell ya.