Potential Winter Storm March 6-7

[Allsnow]

Ccb over NYC hr 75 wow

[Kaner587]

Hr 75 mother of god

Blame it all on the ULL....if it squashes the thing off the NC coast or if it splits and phases is giving us one hell of a lucky snowstorm, it's all the ULLs fault

[Edge Weather]

Wow, I''' be damned.  Nice hit between 72-78 hrs. 

[Kaner587]

There's a poster on the Sne thread who tried to call it early and say it was a huge cave to the euro. Oops. 0.75-1in precip over southern mass and were still sitting in the Ccb moderately precipitating (snowing?) at 81. Big hit

[MJO812]

Still going on  at hour 81. WOW

[earthlight]

New England gets absolutely demolished after 78 hours

 

QPF totals are 1"+ for NYC...more in Central NJ.

 

Looks like 1.75" for Boston

[Absolute Humidity]

I just believe in its ability to see specifics that the lower res Ncep models miss . ( Sref and nam outside 48 hrs ) One day the euro will puke a prog and when it does , us euro lovers will look like idiots.

The NAO s depth creates enough confluence as well as presses on the SE ridge

So it's flatter. I just can't argue with it , as much as I would personally love it to be wrong.

Thers a reason the private forecast community rely on it more. Just sayin.

As I type the 0z GFS is in. Either im genius or a douche. See u after the euro. Lol

Yes, GFS is a wet dream run. It has Great Lakes energy pulling it north. Still, I can't get excited with it and would be seriously shocked if the EC did anything like this. But still wow, what a dramatic shift.

[Blizzardo]

Still need to see the the euro hang a left...

[Kaner587]

Honestly I still don't buy it, however, dynamically it makes a lot of sense. Without that phase it gets shunted se and we see very little a la the nam or euro. Thing is no other model except maybe the srefs shows anything like this occurring. Would love to see some agreement with the 500mb features before jumping on this. But damn what a solution

[Storm At Sea]

This was predictable.

[earthlight]

[earthlight]

The 10m wind field expands pretty dramatically as this thing comes up on the coast on the GFS. The GFS looks like it has 55mph 10m sustained winds on Eastern LI at 84 hrs.

[Mitchel Volk]

If the great and powerful agrees with the GFS then we can say mother of god, until then hold your horses, thou I do like this pattern for this type of storm.

[SnowyCane22]

The real question is how much of the qpf would be snow as opposed to rain? even so proceed with extreme caution...still awesome to see

[Kaner587]

Earthlight drop some wisdom on us here...the wait over the next several model runs will be excruciating. How do you feel about the ULL split and phase? There is tremendous blocking which favors phasing for sure, but this seems so on its own right now

[earthlight]

If the great and powerful agrees with the GFS then we can say mother of god, until then hold your horses, thou I do like this pattern for this type of storm.

 

Yeah I pretty much agree..if the Euro remains the same I will have a hard time weighting more than 10% of the NCEP solutions into my forecast.

[WintersGrasp]

Of course not the final solution but definitely good to see

[sn0w]

Apparently the Ukie is still south of us but north of its previous run?

[KEITH L.I]

Wish I could trust the GFS..I try,ya know.It's like crying wolf,it sucks you in.But experience says wait for Euro to get on board

[NorthNJwx]

There is a 45-50 kt wind contour over the S fork of LI at 84hr. That's a NNE wind; due N or NNW further west along the coast, going down to NJ and the Delmarva. The duration of ENE-NE winds over coastal areas is less on this run due to the increased northerly movement of the storm, so coastal flooding issues would probably be less than on previous runs. 

 

Amazing to see the models diverge again at this stage. 

[Zir0b]

Earthlight drop some wisdom on us here...the wait over the next several model runs will be excruciating. How do you feel about the ULL split and phase? There is tremendous blocking which favors phasing for sure, but this seems so on its own right now

We don't know if the GFS is on its own right now...let's wait for the rest of the 0z global models. Remember the GFS was the first cycle of runs  to bring the boxing day blizzard back, 

[WintersGrasp]

Gfs has hiccuped with this storm already

[tmagan]

Here is an example of blocking... a system which has snow nearly on the doorsteps of KMSP, is forecast to be still affecting us Friday morning via the GFS.

[Kaner587]

We don't know if the GFS is on its own right now...let's wait for the rest of the 0z global models. Remember the GFS was the first cycle of runs to bring the boxing day blizzard back,

HM had a great post over in the mid Atlantic forum. Basically the split doesn't do so much initially but it meanders so far west over and onto Lake Ontario that it allows room for amplification between the original ULL and the new one. Something like this happened during dec 19 2009. The split occurred further northwest I believe, but without it we would have been High and dry.

[earthlight]

Earthlight drop some wisdom on us here...the wait over the next several model runs will be excruciating. How do you feel about the ULL split and phase? There is tremendous blocking which favors phasing for sure, but this seems so on its own right now

 

But isn't that the fun part? In the summer, when we're on here tracking a 40dbz garden variety thunderstorm that has a severe thunderstorm warning on it, won't you wish we were doing this instead?

 

I think the most intriguing part about this entire setup is how the guidance is handling the three features which are on the board (all somehow, magically within the northeast us grid frame on ewall) after 48 hours. If you check out the image below,  the GFS initially looks like it will whiff to the south and east. The entire flow is oriented that way from the get go as the ULL comes out of the Plains and dives south and east underneath the fast flow to the north and blocking. However, some crazy interactions occur aloft that I think most people are missing. These will determine where the storm tracks and where the precipitation field ends up. The two very important features are

 

1) The ULL to the northeast of the main shortwave in the Northwest Atlantic. This feature is crucial for more than one reason as it not only acts as a confluent provider early on, but then it actually begins to interact with the shrotwave over the Mid-Atlantic. Look below and watch the feature highlighted. At first it is situated over the Northwest Atlantic and elongates to move over New England. As our shortwave shifts through the Mid-Atlantic, it actually retrogrades west and interacts with the northern periphery of the shortwave to the south. This is very important as it allows for a very brief but incredibly essential height rise along the coast.

 

As a result of this the precipitation shield can expand to the north and west instead of continuing to be shunted off to our south and east. The surface low can eventually slowly travel north and east along a very narrow highway as that feature moves out of the way back to the west over Western New England. The eventual track of this feature will not only determine the track but also the best jet dynamics and whether or not they will allow precipitation to expand into our area. The NAM has this aligned very poorly and the precip shield never has a chance.

 

2) The northern stream feature dropping in from Southeast Canada. Every run of the GFS has trended farther south and east with this feature with more interaction since last night at 00z. This is arguably more important for New England as it eventually phases in and kicks off new development. This is why you're seeing a secondary QPF max develop eventually over New England on the GFS. It also helps the height field orient in a better manner for us on the tail end of the CCB influence on the GFS.

 

But this is all fun and games for now. Until we see shifts from the more reliable guidance (who am I kidding, the Euro and its ensembles), I think we'll have to take these developments as interesting but not "mother of god" status. The NCEP models have not only had a history of shenanigans in this time frame, but have had a specific history with bringing surface lows and precipitation shields too far north and west. And although every storm system is different, this would be an ideal situation for them to play into that bias.

 

We will see.

 

 

 

 

[Weathergun]

Apparently the Ukie is still south of us but north of its previous run?

 

It looks somewhat further north than last run. Much more northern stream interaction.

 

[Kaner587]

Thanks earthlight amazing explanation. Ukie shows somewhat of a similar situation with the energy over upstate NY and is north of 12z but at 72 hard to say how similar the end result would be to the GFS

[Zir0b]

HM had a great post over in the mid Atlantic forum. Basically the split doesn't do so much initially but it meanders so far west over and onto Lake Ontario that it allows room for amplification between the original ULL and the new one. Something like this happened during dec 19 2009. The split occurred further northwest I believe, but without it we would have been High and dry.

I remember that vividly and alluded to that event yesterday. I definitely recall that PV sitting north of Maine suppressing the storm south...until some of the model runs started magically splitting the pseudo 50/50 low into two pieces like Moses split the red seas...this looks like a different set-up though 

[CooL]

Based on the ukie h5 map posted it looks like it just missed a big time phase

[Zir0b]

It looks somewhat further north than last run. Much more northern stream interaction.

I think that is MORE than somewhat more north.. the 12z ukie below... 0z Ukie shows the northern stream pulling it back further north as well as aligning a classic negative tilt look...but not quite to GFS level but a step towards it for sure