18Z Euro at fast glance without seeing snow maps would seem to have heaviest snows bounded by FWN-CDW or so but it was a rough glance. It seemed less impressive for central to southern NJ and inched its way closer to NYC but not there yet
It looks to me to still have the best snows over NJ to their W-NW but it’s been creeping East with that area. It won’t take much to get it over NYC but with marginal temps the snow accum maps are gonna be way off. I think 4-7 with maxes of 8-9 will be the best anyone sees there
BOS might get a brief window depending how that sleet line advances. One of the mesos, The 3Km NAM I think hinted that they’d change over at 00-01 but then have a period of heavy PLSN at 03-04Z just ahead of the complete changeover to rain
This is the typical early season lousy snow growth setup where radar looks impressive suggesting mod snow 1/2SM but Logan is 33-35 in east flow and does not have temps supporting good snow growth. I had them getting 4-5 but I doubt it happens now.
There has been an ever so slight nudge east it seems at 12 and 18Z today overall but probably still need a 30-50 mile shift. That can more or less occur simply off average model error by this time tomorrow
The temps are so marginal and the band likely won't be as expansive as modeled so those totals will be limited to small areas. I would expect you'd see mostly 4-7 with isolated area over that
The good news for the snowhounds is that the 3km NAM was by far the best model today on ptype/changeover time. If it holds its idea for tomorrow the snow axis is definitely further east than the other guidance.
Winds flipping 070-080 now at JFK. that mini wedge is starting to be punched out. All await that T measurement from NYC now....it was about a half inch here
The temps at 10K tomorrow afternoon and evening are right at the threshold of what you want to get enough boundary layer cooling in and near the CCB behind a system. DT/Cranky often mention this that if you don't have -10C or less you won't consistently get snow or accumulations.
Yeah you’ll usually do well in NYC with a low in that spot when the system is close to stacked and closed. There’s always a rare instance where you can be skunked because of various factors (such as cold air supply as you mentioned earlier) but it’s hard not to at least get a few inches
And it seems the maturing of the surface and ULLs has trended a bit faster today. No question we saw on yesterday's runs that process was getting delayed which led to some of the dud model runs
This is really a bad storm for the GFS weaknesses. Cold air is marginal and its a fairly complicated evolution. Its no surprise the UKmet/Euro look different
I am going with a blend of the Euro/UK for now. GFS I always toss til inside 24-30 on these events. NAM cannot be trusted til it shows the same scenario 2-3 consecutive runs. When the NAM consistently shows something big its usually right. Any jumping back and forth and you can typically toss it
The one change today is the models seem to be starting to mature the low faster again offshore. They slowed that process somewhat yesterday which led to lower amounts
Yeah assuming no massive 00Z shift my guess is at 4am they issue a WWA for monday afternoon and evening for 2-4 or something. I'm not sure they won't issue one for tomorrow too from 10am-2pm just because its first event of year but technically the event tomorrow falls short of criteria