January 25-26 Winter Storm Potential

[LVblizzard]

7 minutes ago, Kevin Reilly said:

I think this is the typical as the precip tapers lightens up it no longer can pull the cold air through the column and resulting in a little Frz snizzle pellets then cold air crashes back down for another period of snow 1-2” typical in lot of our 12”+ storms. 

February 2014 was like this. Still gave ABE 16”.

[The Iceman]

12 minutes ago, LVblizzard said:

February 2014 was like this. Still gave ABE 16”.

Feb 2021 was like that too. Huge front end thump turning to sleet then ended as light snow. I know my total was over a foot, can't remember the exact amount at the moment. 

[JTA66]

21 minutes ago, Ralph Wiggum said:

Spoken from the Godfather of KU storms, the literal U in KU, the man who co-authored the NE US snowstorm "bible". I am preparing now for the massive letdown over the next 90 hrs. 

Kind of hard to ignore his take. Waiting for 0z with the additional data from the recon flight.

Buckle up!

[Mikeymac5306]

1 minute ago, JTA66 said:

Kind of hard to ignore his take. Waiting for 0z with the additional data from the recon flight.

Buckle up!

 

[The Iceman]

Not sure if this has been posted yet, but great AFD by Mt Holly

 

Quote

KEY MESSAGE 3...Confidence continues to increase the area will
be affected by an impactful winter storm beginning Saturday
night and potentially lasting all the way into Monday. Portions
of the area are likely to see moderate to heavy snowfall but
there remains uncertainty on where the heaviest amounts will
fall.

Low pressure will begin organizing itself near the Texas Gulf coast
Saturday. This will occur as several pieces of upper level
energy dive southward into the base of the persistent long wave
trough dominating over the CONUS. Saturday night into Sunday
these pieces of upper level energy will to at least some degree
"phase" with one another helping to drive deepening surface low
pressure through the southeastern states then north and east
towards roughly around the Virginia coast by late Sunday.
Forecast guidance has continued to trend northward with the
placement and the track of the low due to better phasing of
upper level energy as just noted. However there continues to be
some uncertainty regarding more specific details and this will
ultimately affect the storms track, speed, and strength. This
will impact where the heaviest precip falls along with precip
types. Nevertheless, confidence has grown that much of the area
has a good chance of seeing moderate to even heavy snowfall
totals with this system. The NBM probabilities of 6+ inches with
this storm now range from around 60 percent over the southern
Poconos to the 80 to 90 percent range near and south of the
urban corridor. Guidance is also in good general agreement that
total QPF amounts with the system have the potential to be 1+
inches in many areas. The main challenge is again, the track of
the low which determines who gets the heaviest precip and if we
actually get into any mixing limiting snow amounts. The GFS has
trended north putting much of the area in the "sweet spot" for
very heavy snow amounts. However the GEM and ECMWF have trended
north as well and now track the low close enough to Delmarva
that mixing may occur at the height of the storm late Sunday.
Regardless, expect snow to most likely start breaking out over
the area Saturday night into Sunday morning. All areas look to
certainly be cold enough initially to see all snow. In fact lows
Saturday night look to once again be down into the single
numbers north with teens to around 20 farther south.

Heading into the day Sunday, expect snow will be continuing across
the area and may fall heavy at times along with NE winds starting to
increase, especially along the coast. Late day Sunday into Sunday
night is when southern portions of the CWA (mainly Delmarva into
adjacent portion of south Jersey but potentially as far north as
Philly) could see some mixing if the low takes a close enough track
to the area. However given the strong artic high and antecedent cold
airmass in place, plain rain looks less likely than a mix with or
change to sleet and freezing rain if any mixing does in fact occur.
If this mixing does occur for a time, a change back to all snow is
likely later Sunday night into early Monday before precip winds down
across the area into Monday.

As already mentioned, a lot of uncertainty remains regarding total
snow amounts. 24 hours ago this looked like more of a question
of a near "miss" to the south vs. a big snowstorm. Now it`s
looking like a more or less a lock that this storm will affect
the area with significant precip with the question then shifting
to whether the track actually gets too far north to bring a mix
or changeover into the area. If this occurs, the very heaviest
snow amounts may end up near or even north of the urban corridor
vs coastal and southern portions of the area. We say this while
stressing the fact that the very heaviest snow amounts within
these type of large systems are still often only 100 miles wide
or less. S/E of the snowfall max you get ice or rain vs. N/W
precip amounts are lighter. For this reason, it will still take
at least a couple more forecast cycles to have a clearer idea on
the details of where any "blockbuster" snow amounts could occur
within our County Warning area.

 

[Duca892]

25 minutes ago, Ralph Wiggum said:

Spoken from the Godfather of KU storms, the literal U in KU, the man who co-authored the NE US snowstorm "bible". I am preparing now for the massive letdown over the next 90 hrs. 

would you say the threat is this turns into just an all out slop storm? 

[Franklin0529]

10 minutes ago, Duca892 said:

would you say the threat is this turns into just an all out slop storm? 

Worst case I think would be the CMC. Heavy thump then sleet. I have a hard time seeing this being slop. Not with that cold air in place 

[Kevin Reilly]

57 minutes ago, CoolHandMike said:

Thanks! So it's not an acronym for anything?

No just means huge snowstorm incoming 

[Violentweatherfan]

1 hour ago, JTA66 said:

Stolen from a red tagger in the MA forum...

I had lunch with Louis Uccellini about an hour ago. He's very concerned about a westward trend going forward. Especially with an 850 low going into the OV. He's not convinced (at all) that the current evolution will hold. 

"I'd rather be in Chicago"

Probably referring to the impending ice storm freezing rain mess that is about to hit the MA area

[dssbss]

Hello,

So, just wondering.  I know there is some chatter now around mixing.   We aren't talking regular rain right?   This would be sleet or freezing rain?    I can remember some times probably 1994 when we had 15 degrees and freezing rain in northwestern skook.   That was a winter to remember.

[Hurricane Agnes]

This is why I hate this time frame - the "mid range".  Someone needs to develop a good "mid range" model because the shifts between the long range and mid range, are almost always nerve wracking!  Hopefully when we get into NAM range, which will start tomorrow, we'll see stuff nailing down more.  The 12k NAM is running right  now and the end frames may capture some of it.

[PhiEaglesfan712]

3 hours ago, ChescoWx said:

Our best storms always have some non-snow in the mix.

This would be almost like the January 2022 storm. I'll gladly take this and run.

[Newman]

What I'm really interested in monitoring in modeling over the next couple days, outside of the typical synoptic features:

1. How does the heavy WAA banding translate northeastward towards SE PA? Does it weaken as the primary dies off and the coastal transfer occurs, or does it plow through the area with vigor?

2. Where do our DGZ layers (could be more than one) set up and do we have any deep omega through these layers? Even if the surface is frigid, poor snow growth could still occur if the omega and DGZ do not align.

3. Where the 700mb FGEN band sets up on models, because IRL it almost always ends up further north

[RedSky]

31 minutes ago, Hurricane Agnes said:

This is why I hate this time frame - the "mid range".  Someone needs to develop a good "mid range" model because the shifts between the long range and mid range, are almost always nerve wracking!  Hopefully when we get into NAM range, which will start tomorrow, we'll see stuff nailing down more.  The 12k NAM is running right  now and the end frames may capture some of it.

I think your on to something a mid range model by combing the GFS and the NAM 

OH DEAR GOD NO

[Hurricane Agnes]

18z 12k NAM last frame shows the beginning of it.  

 

[JTA66]

1 hour ago, Violentweatherfan said:

Probably referring to the impending ice storm freezing rain mess that is about to hit the MA area

True. His thoughts may have been more directed towards the Balt/DC area.

[Hurricane Agnes]

18z ICON just got done.  Here is out to 120 hours - 

[Duca892]

1 minute ago, Hurricane Agnes said:

18z ICON just got done.  Here is out to 120 hours - 

ICON took a step north i believe, or QPF is lower, hacked off about 3-4ins from the LV from 12z to 18z

[Ralph Wiggum]

18 minutes ago, JTA66 said:

True. His thoughts may have been more directed towards the Balt/DC area.

Well, icon is a big hit for Chicago with mostly a sleet event for extreme se pa points s and e. Never doubt either one of the KU duo...never.

[Hurricane Agnes]

29 minutes ago, Duca892 said:

ICON took a step north i believe, or QPF is lower, hacked off about 3-4ins from the LV from 12z to 18z

The ICON goes way west, with the Gulf low coming up through the east central, almost like an apps runner, and then it pops out off the Jersey coast. 

18z GFS is running so will see what that shows.  This is why I hate this time frame! 

[Violentweatherfan]

25 minutes ago, Ralph Wiggum said:

Well, icon is a big hit for Chicago with mostly a sleet event for extreme se pa points s and e. Never doubt either one of the KU duo...never.

PSU Huffman said this isn’t going anywhere near Chicago with that monstrosity HP in place

[RedSky]

18z G south

 

[Ralph Wiggum]

15 minutes ago, RedSky said:

18z G south

 

Ai north

[Ralph Wiggum]

An air brigade is currently en route to the pacific to gather data for the 0z runs in an otherwise sparse data area. 

0z runs are going to do 1 of 2 things imo, either really amp this system and track it farther N than we want or guidance will have a better slp handoff and nudged south. I think we will almost certainly see some big ticket changes.

[RedSky]

12 minutes ago, Ralph Wiggum said:

Ai north

ECM Ai looks wonderful

[tcutter]

2 minutes ago, MillvilleWx said:

For clarity sake

Data ingest is ONGOING and will be available for the 00z runs TONIGHT (00z 1/22)

There has been NO RECON DATA FOR TODAY (1/21). 
 

Thanks

 

[Duca892]

GFS definitely south. Think that’s the first model run all day I’ve seen with the LV with less than 10in

[The Iceman]

9 minutes ago, RedSky said:

ECM Ai looks wonderful

It’s barely waffled the last few days either. Definitely N trend but not large shifts run to run. Definitely has been the most consistent at least. It was money last weekend.

[The Iceman]

Leave it to the GFS to swerve south while everyone else ticks N lol

[LVblizzard]

And that’s why it’s known as the GooFuS!