March 12-15, 2023 | NE / Mid-Atlantic Winter Storm

[so_whats_happening]

9 minutes ago, StretchCT said:

Anyone know if the SREF plumes use 10:1 or is it their own special ratio

 

5 minutes ago, MaineJay said:

I am pretty sure they use ratios.  Not sure the calculation.

Pretty sure you would have to look at QPF output in 'snow' and then base the ratio off that but im pretty certain it is 10:1.

[so_whats_happening]

Definitely trying to consolidate the energy off the coast better again still going deeper in the trough and further SW with trough axis and lead vort.

[MaineJay]

27 minutes ago, so_whats_happening said:

 

Pretty sure you would have to look at QPF output in 'snow' and then base the ratio off that but im pretty certain it is 10:1.

This one member is 10.6:1. So not exactly 10:1.

 

[so_whats_happening]

Per this run of the NAM it captures the developing low around 100-150 miles SE of LI. You can see how the PVA or cyclonic vorticity follows the system until the 500mb low is over top it a the end near the tip of Nantucket. Still feel the models are muddy at the beginning of storm development with that vort piece as some of the models tried to do a double low. I think the placement of the low may come in a little closer to Delmarva/NJ area initially rather than being depicted further SE but that is just small changes overall it seems reasonable where we are at now is a solid solution. May have a two maxima snowfall one up in the area south of Albany from just east of Binghamton to western Mass and another showing up near Eastern Mass as the column cools from rapid development. We are pretty close to a bombing out storm 24hr 24mb.

NWS doing a good job at highlighting terrain.

[StretchCT]

43 minutes ago, so_whats_happening said:

 

Pretty sure you would have to look at QPF output in 'snow' and then base the ratio off that but im pretty certain it is 10:1.

I'll try when it's all snow

[so_whats_happening]

Now that seems like a really good look for the potential with this. If only there was an arctic airmass and only if this was say 200 miles SW lol

Feel it may be a little underdone for western Mass

Edited March 12, 2023 by so_whats_happening

[StretchCT]

This comment in the AFD needs to be noted. Gotta go though.

By Monday night, the upper level low forces the coastal low to
rapidly deepen as it passes near the 40N 70 W benchmark. Some model
guidance actually has a separate area of low pressure develop
over the area in the apex of the inverted trough. This will
result in widespread moderate to locally heavy precipitation
Monday night into early Tuesday morning. Rain along the coast
may be heavy at times through the night. This is likely when a
bulk of the precipitation from the event falls with coastal
areas possibly seeing as much as 1.5 inches of rainfall from
sunset Monday to sunrise Tuesday.

[MaineJay]

Mt Washington, same SREF member as before.

12:1 SLR

The SREFs do use ratios, not pegged at 10:1.

[PA road DAWG]

Seems very reasonable imo 

[NEPAsnow]

[JDClapper]

[PA road DAWG]

12 minutes ago, NEPAsnow said:

This won’t verify. I think you’re going to see a late game shift NORTh and northeast.  Just like we’re starting to  see now in the latest model runs  

[PA road DAWG]

Gfs with a big shift north northeast.  I knew this would be coming 

Edited March 12, 2023 by PA road DAWG

[Poco]

18z hrrr was interesting to say the least 

 

[so_whats_happening]

Just now, Poco said:

18z hrrr was interesting to say the least 

 

Wow you can even see the 500mb low over OH/ WV area. That would be something to watch.

[PA road DAWG]

Seems very reasonable imo.  

 

297A492D-4240-43BE-89BD-50F7E5EC8BFE.webp

Edited March 12, 2023 by PA road DAWG

[PA road DAWG]

2 minutes ago, Poco said:

18z hrrr was interesting to say the least 

 

Low over NYC??! 

[Poco]

This is going to be down to Nowcast and how the surface low and precipitation field sets up.  There will features in the backwards J trof that will localize very heavy snows from poconos on north.   Digital snow is cool and all but I’d much rather the real thing. 
 

that is if I wanted snow at all right now, which I don’t.  (It’s boat time, need to fish) 

[so_whats_happening]

8 minutes ago, Poco said:

This is going to be down to Nowcast and how the surface low and precipitation field sets up.  There will features in the backwards J trof that will localize very heavy snows from poconos on north.   Digital snow is cool and all but I’d much rather the real thing. 
 

that is if I wanted snow at all right now, which I don’t.  (It’s boat time, need to fish) 

Yep pretty much, come on down this way been almost boating season for awhile now lol

[Poco]

I think a lot of modeling is still having trouble depicting just how the two parcels of energy consolidate.  I’ve watched multiple models for days now  try and depict the surface low next to a small vigrous vort max that stays spun up at h5 in the southern stream.  I really don’t see that happening as is being depicted.  This type of storm always usually results in a singular energy field and how the ULL occludes as it reaches for the coast.   This ull has trended deeper for days and at this point I’d be surprised if the initial moisture field doesn’t reach over Eastern and east central PA.  How long it stays or if the pivot causes Banding on the westward side of the trowal I’ll just wait and see.  What I won’t be doing is watching anymore gfs runs 

Edited March 12, 2023 by Poco

[PA road DAWG]

1 minute ago, Poco said:

I think a lot of modeling is still having trouble depicting just how the two parcels of energy consolidate.  I’ve watched multiple for days now  try and depict the surface low next to a small vigrous vort max that stays spun up at h5 in the southern stream.  I really don’t see that happening as is being depicted.  This type of storm always results in a singular dnergy field and how the ULL occludes as it reaches for the coast.   This ull has trended deeper for days and at this point I’d be surprised if the initial moisture field doesn’t reach over Eastern and east central PA.  How long it stays or if the pivot causes Banding on the westward side of the trowal I’ll just wait and see.  What I won’t be doing is watching anymore gfs runs 

I guess it’s called goofus for a reason 

[Poco]

1 minute ago, PA road DAWG said:

I guess it’s called goofus for a reason 

I don’t think the gfs even had a storm at 18z 5 days ago.  If I recall correctly 

[Poco]

Just now, Poco said:

I don’t think the gfs even had a storm at 18z 5 days ago.  If I recall correctly 

it’s not my favorite that’s for sure 

[LiveWire_13]

29 minutes ago, PA road DAWG said:

Low over NYC??! 

Low over NYC but no moisture from Manhattan through the Atlantic but only in a narrow corridor? How the hell does that happen, let alone the fact it seems incredibly unlikely.

[Chinook]

I don't really have any interest in who gets a lot of snow or not, as I don't know anybody personally in this region.  Here is the 10:1 ECMWF vs the "dynamic ratio" ECMWF. The 12" contour is almost in the same spots but not quite. Then there are differences when you get to much higher values.