Central PA - Winter 2021/2022

[pasnownut]

14 minutes ago, GrandmasterB said:

Nice seeing a cluster of lows to the west of the mean.  As pointed out by Blizz93, some of those are strong and close to the coast.  Interesting.

It sure keeps hope alive...and hope the 0z's dont buck that trend.

 

[Ruin]

Snow cut off makes no sense to me. Storm this powerful that trending more West just cuts off snow this drastic ????? Sine people are saying online claiming it's to powerful so it's compact 1 the storm is huge 2 I've seen sub ,960mb dump snow back to Ohio 

[GrandmasterB]

Looks ok to me

[pasnownut]

God I wish the NAM went beyond 84.  We would likely all be a tad more giddy.  Cuts back a bit on the NS precip, but makes up for it w/ a really nice SLP just off NC VA coast and is notably south of GFS.  Verbatim it would give the coastal time to get crankin.  REALLY like the look.  Here's to hopin the rest of the 0z's keep this trend going.

 

[Bubbler86]

@Itstrainingtime   @Atomixwx, the Wiz just made the Sizers Clipper collapse look like Childs play.  Maybe a top ten ever NBA collapse.   Lost a 35 point 2nd half lead and give up 7 points in the last 8 seconds. 

[Blizzard of 93]

3 minutes ago, pasnownut said:

God I wish the NAM went beyond 84.  We would likely all be a tad more giddy.  Cuts back a bit on the NS precip, but makes up for it w/ a really nice SLP just off NC VA coast and is notably south of GFS.  Verbatim it would give the coastal time to get crankin.  REALLY like the look.  Here's to hopin the rest of the 0z's keep this trend going.

 

Yes, very nice NAM run!

More room to improve surface in time if that 500 look holds.

[Blizzard of 93]

7 minutes ago, GrandmasterB said:

Looks ok to me

Lol, that is beautiful.

[Bubbler86]

9 minutes ago, GrandmasterB said:

Looks ok to me

Trough a tiny bit too far west (IMO) at 84 but also think that as depicted, the Nam precip shield should be more expansive at 84. 

[pasnownut]

3 minutes ago, Ruin said:

Snow cut off makes no sense to me. Storm this powerful that trending more West just cuts off snow this drastic ????? Sine people are saying online claiming it's to powerful so it's compact 1 the storm is huge 2 I've seen sub ,960mb dump snow back to Ohio 

Guessing that's because of the arctic boundary pressing/interacting w/ coastal, and causing sharp cutoff.  500's are once again a bit more neg tilt and should help to tuck the LP closer to coast, but that boundary likely is culprit IMO

[Ruin]

Ty no one said this at all hope the storm can blast the boundary apart lol

[vortmax]

Great read from ALY AFD:

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Main story for the long term is a strong coastal storm that may
impact the region Friday night into Saturday. At this time,
there is high confidence that a storm will develop, but low
confidence as to the track. While there is the potential for a
major storm for somewhere in the northeast, considerable
uncertainty in the storm track means that impacts to our
forecast area remain uncertain as well. It is too early to
estimate snowfall amounts, but will include a full analysis of
current thinking and sources of uncertainty below...

At 00z Saturday, long term begins with a large upper trough
extending from Canada down to the Gulf Coast moving across the
eastern third of the country. As this trough moves eastward Friday
night and Saturday, it will become neutrally to negatively tilted,
and surface cyclogenesis will take place off the U.S. east coast. As
this storm tracks northeastward, it is expected to rapidly deepen,
and may undergo bombogenesis (drop in central pressure of 24 mb in
24 hrs). With ample cold air in place, expecting precipitation to
fall as all snow for our region. Also, it will become breezy due to
a tight pressure gradient over the region, with some sources of
guidance suggesting the central pressure of the storm deepens into
the 960-970 mb range. Snow may begin as early as late Friday
afternoon and last into Saturday night, with the highest chance for
snow during the day Saturday.

While confidence is high in an impactful storm somewhere along the
east coast, there are several sources of uncertainty in the storm
track and therefore impacts to our region. One major source of
uncertainty is the degree of phasing on Friday between a northern
stream disturbance diving south from Manitoba and a southern stream
disturbance over Texas and New Mexico. At this time, it appears the
norther stream disturbance will take a favorable track for these
disturbances to phase, but there are more questions surrounding the
southern stream. The GFS is stronger and further to the southwest
with the souther stream disturbance, resulting in a later phase/less
phasing between the two disturbances. The result is a more
positively tilted and progressive upper trough and a storm track
further to the east. The Euro, on the other hand, has a weaker
southern stream disturbance that does not dig as far south and west.
This allows the southern stream disturbance to move out ahead of the
norther stream wave Friday and Friday night. The result is a more
negatively tilted upper trough and a storm track further to the
west. The Euro has held steady over the past few runs, while the GFS
has trended towards the Euro each of the past three runs after the
18z GFS yesterday was much further east with the storm track.

To add even more uncertainty to the forecast, Stony Brook
Sensitivity analysis developed through CSTAR research suggests that
the eventual track of the storm will also be sensitive to the
strength of the upper ridge that develops downstream of the trough
(as is usually the case with these large east coast storms). A
stronger ridge will be associated with a storm track further to the
west; this is seen in the Euro solution as well. Often, but not
always, models underestimate the strength of the downstream ridge in
the medium-range as they cannot resolve the diabatic ridge-building
due to latent heat release. With ample moisture from the Gulf of
Mexico, it is certainly possible that this trend will manifest
itself with this storm as well. Will note at this time that both the
GEFS and EPS have a subset of ensemble members tucked in closer to
the coast than the operational models suggest, suggesting that a
track further north and west remains possible. Finally, right
entrance region of an  upper jet over our region and the fact that
banded snowfall on the northwestern side of major east coast
cyclones often occurs further north and west than modeled, there is
still the potential for a precipitation shield that extends further
to the west than guidance shows. Therefore, accumulating snow is
possible further west than modeled, even with the eastern storm
track. Hopefully, will be able to gain more insights into possible
solutions by comparing model guidance to RAOB observations over the
next 24 hours as upper energy comes onshore.

[Blizzard of 93]

7 minutes ago, vortmax said:

. Will note at this time that both the GEFS and EPS have a subset of ensemble members tucked in closer to the coast than the operational models suggest, suggesting that a track further north and west remains possible. Finally, right entrance region of an upper jet over our region and the fact that banded snowfall on the northwestern side of major east coast cyclones often occurs further north and west than modeled, there is still the potential for a precipitation shield that extends further to the west than guidance shows. Therefore, accumulating snow is possible further west than modeled, even with the eastern storm track.

This is a fantastic discussion, but the part that I just quoted is what should keep us very much in the game.

[canderson]

Don’t think this was posted 

 

[canderson]

0z GFS looks east from its earlier runs fwiw. Friday looks interesting though  

IMO this isn’t our storm - which is fine. This is fun to track for the epic weather it’ll bring SNE. 

[Mshaffer526]

Do yourself a favor and go to bed instead of looking at the GFS 

[GrandmasterB]

7 minutes ago, canderson said:

0z GFS looks east from its earlier runs fwiw. Friday looks interesting though  

IMO this isn’t our storm - which is fine. This is fun to track for the epic weather it’ll bring SNE. 

The 0Z GFS really isn't all that great for SNE.  Boston and Cape do ok but it's nothing historic.

[canderson]

Congrats lobsters? 
 

[canderson]

Just now, GrandmasterB said:

The 0Z GFS really isn't all that great for SNE.  Boston and Cape do ok but it's nothing historic.

Yea I thought it hugged closer - I gave up when it was noticeably east. 

[MAG5035]

Nit picks aside on it shifting it’s swath east a bit (and south some with the initial snowfall development in our neck of the woods), GFS is still showing the same general theme of bombing the coastal storm out later and further east, only catching SNE with the more excessive snowfall. Euro has been exploding this into a big snowstorm starting much further down the coast. It’s a difference between a more run of the mill coastal with localized major snow (GFS) vs a sure fire NESIS cat 3+ considering how much of the megalopolis is within the 10+ in both the Euro and it’s ensemble mean. 

[canderson]

6 minutes ago, MAG5035 said:

Nit picks aside on it shifting it’s swath east a bit (and south some with the initial snowfall development in our neck of the woods), GFS is still showing the same general theme of bombing the coastal storm out later and further east, only catching SNE with the more excessive snowfall. Euro has been exploding this into a big snowstorm starting much further down the coast. It’s a difference between a more run of the mill coastal with localized major snow (GFS) vs a sure fire NESIS cat 3+ considering how much of the megalopolis is within the 10+ in both the Euro and it’s ensemble mean. 

The Euro to me is overamped. (Which seems to be a trend) 

[MAG5035]

1 minute ago, canderson said:

The Euro to me is overamped. (Which seems to be a trend) 

Well on the other hand, we were sizing up 10+ in all the Sus Valley around the D5 timeframe leading up to the 1/16-17 storm and the end game from that was the 980mb low literally going right over my head haha.

Yea that’s probably not happening with this storm but the Euro take is definitely easily in the realm of possibility, or even closer to the coast than that. It depends on the degree of phasing and how quickly it happens. Additionally, this initial area of snowfall that develops with the northern energy is still showing and I personally think with a major amplification like this that this will eventually start showing better QPF wise the closer we get, provided we don’t see a major setback in guidance back towards what it was showing a couple days ago. 

[Ruin]

Models are just sad lol

[MJO812]

40 minutes ago, canderson said:

The Euro to me is overamped. (Which seems to be a trend) 

And the gfs is usually too progressive 

[MAG5035]

Quite cold tonight here, already down to 8ºF. 

[Santa Clause]

Is there gonna be 1 to 3 inch storm Friday either way or was all that from coastal

[Blizzard of 93]

The 0z EPS still gives hope of a more westward track for the coastal with a decent cluster of lows to be he west of the mean low position.

 

[Ruin]

I have another question so yesterday my high for fri was 27 now its all the way to 35? would this signal the storm is closer to the coast? pushing warmer ocean air into our area? or am i reading to much into this I know normally our forecast highs tend to be warmer then they end up being warm bias and all.

[pawatch]

-5 degrees this morning. I need a slight warm up.

Keep and eye on things you never know with these models. But looks like this is up the coast.

 

[Blizzard of 93]

The 6z Euro still gives hope to the LSV.

On to 12z

[Blizzard of 93]

Here is the 6z Euro snow