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Virga really isn’t a concern in a setup like this. Yes, the antecedent air mass is dry, but this is a deep, dynamically forced system with strong large-scale lift. Once precipitation starts, the column moistens very quickly. Virga issues tend to happen with weak forcing, shallow lift, or fast-moving systems trying to overcome dry air. A closed H5 low with sustained ascent overwhelms that problem. You might lose the very first echoes to evaporation, but not the storm itself.

Looks like surface temps are closest to the GFS at this point.

So why’s my comment about the 93z thing deleted but the others stayed?

things seems to be zeroing in on a solid to major hit for the southern and eastern portions of the sub would need a real nice needle threading to get the goods this far nw and that's looking less likely than 12 hours ago imo

From H5 (500 mb) height, we are looking at exactly the setup that has a high potential (high ceiling) for the NYC area for a major winter weather event. The ECMWF depicts a then fully closed 500mb low in the Northeast with large negative height anomalies and a slow pivoting flow. It represents a true 500 mb closed low, that is no longer open or progressing as a trough. It is vertically coherent, dynamically mature and no longer associated with the fast zonal flow of upper levels. The closed 500mb low will eventually be around for a period of time, not a question mark of how long. A compact and centered cold pool aloft is also critical to snow production efficiency. Closed mid-level lows create steep lapse rates, which in turn create significant lift and space throughout the region to support snow band formation, and through the mesoscale process create the large snowfall totals in NYC. Most storms that produce over 18 inches of snow are not continuous, steady snowfall, rather they are created by the time and conditions that create the most snow through banding.

Nam might have delivered with weenie extrapolation.

Only to 78 hours here, but a good trend based on surface output. Ignore the numbers as this is probably sleet.

This is the way

AND CLIMBING!!!! *should totally start using DBZ terms to describe the storm*

I just mentiond that a few minutes ago and with this arctic airmass I would suspect there will be virga

The 18z NAM is better than the 12z and was about to obliterate us...and that is the end of my analysis of the NAM at 84 hours.

ITS OVER 9000!!!!

WGAL on the record saying 12 or more likely.

Given the stretch we’ve had the past few years I think most on here should be happy that we are probably going to be able to lock in at least 6”- 10” for most of the SNE forum. If it’s more than that great but I for one won’t be complaining about missed potential if I “only get” 8”.

The secondary low has a fairly tight spread. What is the timing for the secondary low to take over?

Excuse my ignorance but what are the chances this falls as virga since I am assuming the air will be bone dry? I can remember a storm or two where we had the precip overhead but never made it to the ground for the duration.

so 36/51 members are wins?

Composite vs 1km Above Ground Level radars

NAM at 84 hours is about as useful as me trying to draw a random map but given it tends to overamp the fact it's flat in the long range is probably a good sign if you're concerned about mixing.

NAM is out of range so take it with a grain of salt but it had a nice front end thump.

How the hell does this happen??

Virga vs fallen

I think in this setup it's gonna come in hot and heavy and the vast majority of our QPF will be before 18z on Sunday and maybe even before 15z. Without a 2 part coastal thing thats usually how it goes. Just some light stuff from these panels on.

Look at where that big northern shortwave enters the country around 78hrs. Much farther east than 12z. Continuing to 84hrs, part of the difference is speed, but it’s still east. I like that. Would like to see that same thing on the varsity models.