January 7th 2022 Snowstorm Threat

6z Euro is west, looking a bit more like the meso models. Pretty much just leaves the GFS in the eastern camp

As one would expect guidance on the track is all over the place. Some hugging the coast and others east of the BM. 06Z Euro op is BM track, but ensembles are well east of BM. More clarity today's runs most likely. Due to the cold temps I think 2-4" is reasonable expectation and any more depends on the strength of the s/w. If that is vigorous it will will tend to hug the coast more (as per Canadian) and parts of the area will have a shot at 6".

Here’s a good look at the upper levels leading into this storm valid on Thursday. All that energy draped across the Great Lakes into northern New England really hurts this storms prospects, because it depresses heights over the east coast.



But the NAM is successful in developing a trough and consolidating the energy at the base much earlier than the GFS, which allows the low to mature faster and raise heights along the east coast. This keeps the storm tracking more west instead of slip east.

Frank- you buying the NAM? Or, you think this slips East and is not a big deal?

I think the east track is more likely, but I definitely think the GFS is under doing the precip considering how much energy is passing over our area. So a blend of both models would give us a 2-4” snowfall. Which could be locally higher where ratios exceed 10:1.

Called last storm well as did SR models. Hope it can go 2 for 2!!

The first HRRR run is in range for Friday’s storm, and is not only quite amplified, but showing a strong signal for an intense snow band that should it verify, could lead to an overperformer along and/or NW of I-95. pic.twitter.com/mzlHLUNeyy

— Tomer Burg (@burgwx) January 5, 2022

This was my first guess map as of yesterday — I’ll update it again later this afternoon.

I’m going to be cautious here since my last guess siding with a NW trend failed, but I do see a *potential* here for a slight NW adjustment & narrow 5-10” corridor from N NJ northeastward. pic.twitter.com/bQCHZj2MIt

— Tomer Burg (@burgwx) January 5, 2022

12z NAM is a wide right

NAM much slower development of the s/w. Absolutely no consistency on this right now.

NAM 06z/12Z are the goal posts with this. Think most everyone sees some measurable snow, but that s/w must develop quickly as this system is moving too fast for dilly dally.

IMO the NAM, at least for now and until it can stumble upon two consecutive runs that are remotely similar, has to be discounted regardless of whether it brings us a widespread warning criteria event or a barely nuisance level event.

MattyICE wrote:IMO the NAM, at least for now and until it can stumble upon two consecutive runs that are remotely similar, has to be discounted regardless of whether it brings us a widespread warning criteria event or a barely nuisance level event.

Yeah, NAM is always going to give extreme solutions, but both solutions ATTM are extremely viable. It's very complex on how that s/w develops. Just the right or wrong tilt/spin makes all the difference in the world.

This is what I'd like to start seeing on the models.  

12Z GFS notice the s/w energy starting to increase before it hit the coast.  That's the path for 6" for someone in the area.

heehaw453 wrote:This is what I'd like to start seeing on the models.  

12Z GFS notice the s/w energy starting to increase before it hit the coast.  That's the path for 6" for someone in the area.

Yupp but the 12z run verbatim was quite ugly

Key to Thursday night snow and how much resides with this weak low coming north from the Bahamas. NAM/GFS jumps the primary to this low quicker resulting in less snow N/W of the low. RGEM, HRRR, and Euro do not as quickly, and more snow is found NW since the primary holds longer. pic.twitter.com/l8By4RpACx

— Bobby Martrich | EPAWA Meteorologist ☈ (@epawawx) January 5, 2022

Interesting

There will be meso banding under where these strong vertical velocities are in the mid levels

3K NAM has had this signature of banding from IBM to LHV for a couple runs now. Interesting.
Rayno still harping on a 3-6" snowfall for NNJ through ELI and into CT.

Same read from Paul Dorian

https://arcfieldweather.com/blog/2022/1/5/j0gsdi9byd5urzlcq0gi82zlyoditb

It’s becoming apparent that the global and hi-res models are having convection issues. The 12z RGEM for example had a low just off the coast then it jumped to a convection blob offshore. Then it inexplicably transferred back to the coast followed by transferring once again to an offshore low. Like that’s going to happen. Also we’re dealing with a small disturbance north of the Bahamas that can throw a monkey wrench into the forecast. I don’t think the models will have a clue until 0z or even 12z tomorrow. Until then windshield wiper is in effect.

HREF in line with other SR model on meso banding. This is a tough call.

That’s a fairly large area of a half inch of liquid which of course is almost double that in the meso bands. I’d sign up for that without a second thought, even without being under one of the bands.

Of course the reality is always if you’re five to ten miles outside or God forbid in between two of the bands you’re most likely scrooed.

Euro 12Z looked much better. It's a step in the right direction. Not really looking at surface panels.

Get to this look about 3 hours earlier and then it will produce.

nutleyblizzard wrote:It’s becoming apparent that the global and hi-res models are having convection issues. The 12z RGEM for example had a low just off the coast then it jumped to a convection blob offshore. Then it inexplicably transferred back to the coast followed by transferring once again to an offshore low. Like that’s going to happen. Also we’re dealing with a small disturbance north of the Bahamas that can throw a monkey wrench into the forecast. I don’t think the models will have a clue until 0z or even 12z tomorrow. Until then windshield wiper is in effect.

I wouldn’t focus so much on where the specific “L” shows up. No it wouldn’t happen like you say, but it would be indicative of there being strung out energies and multiple centers trying to figure out who wants to be primary and who should transfer energy to whom. That’s my interpretation Which is very real and what will limit how powerful a storm can get.

Globals are starting to resolve the meso and ingredients set up I would assume but the mess have the physics and algorithms to pick this up.
SROC pointed it out before with the 3K NAM and the HRRR and HREFs have it as well as the RGEM. Very interesting for sure.

Where and if this PVA sets up can be the difference between 2" and 4".

Also ratios will be 12:15-1 in NNJ on North.

CPcantmeasuresnow wrote:That’s a fairly large area of a half inch of liquid which of course is almost double that in the meso bands. I’d sign up for that without a second thought, even without being under one of the bands.

Of course the reality is always if you’re five to ten miles outside or God forbid in between two of the bands you’re most likely scrooed.

CP, that map that Mugs posted is indicating how much snow could potentially fall per hour depending on the max banding we get, not liquid QPF. In our areas we could potentially be in .50-.75 per hour for a time if we get some banding. I think us folks N and W will see 2-3, maybe 4 if things work out. It's better than nothing I guess.

hyde345 wrote:

CPcantmeasuresnow wrote:That’s a fairly large area of a half inch of liquid which of course is almost double that in the meso bands. I’d sign up for that without a second thought, even without being under one of the bands.

Of course the reality is always if you’re five to ten miles outside or God forbid in between two of the bands you’re most likely scrooed.

CP, that map that Mugs posted is indicating how much snow could potentially fall per hour depending on the max banding we get, not liquid QPF. In our areas we could potentially be in .50-.75 per hour for a time if we get some banding. I think us folks N and W will see 2-3, maybe 4 if things work out. It's better than nothing I guess.

Thanks Hyde. I thought that was to good to be true.

The EPS low pressure members are mostly inside BM at 48 hours.  Ultimately I believe that's going to verify and think it could be closer than this.  It's a question of the speed of intensification as the system is going fast.  Also, it's not necessarily about how low the pressure is when it hits our latitude it's about how fast it's dropping on its approach. A cyclone that maxes out before reaching latitude is like a dead carcass.

amugs wrote:Globals are starting to resolve the meso and ingredients set up I would assume but the mess have the physics and algorithms to pick this up.
SROC pointed it out before with the 3K NAM and the HRRR and HREFs have it as well as the RGEM. Very interesting for sure.

Where and if this PVA sets up can be the difference between 2" and 4".

Also ratios will be 12:15-1 in NNJ on North.

Looks like from that map the same for NYC on north into my neck of the woods, just been watching the forum as been busy with work. Reel this one in guys! Looking more or less or the same in terms of seeing 6+ somewhere?

18Z NAM


18Z HRRR


Glad we have agreement