jm1220

It's probably some ensemble forecast. And no that's not great forecasting. I still remember the debacle that happened when Channel 4 showed 26" of snow from the NAM in Central Park right before Nemo 2/8/13. People freaked out for the 11" it ended up being-significant but not crippling. My guesses for totals: Central Park 2.5" JFK 1.5" LGA: 3" Long Beach: 1" EWR: 3" New Brunswick: 1.5" Morristown: 5.5" Middletown NY: 7" Newburgh: 5.5" Danbury: 6.5" New Haven: 6" Huntington (IMBY): 4" Islip: 3.5" RIverhead: 3" Places I have 3-4" on LI and Newark etc might easily be only 2" or less if we see sleet crashing in, breaks in the precip etc. Tough call.

35 here. Hopefully first flakes soon.

Models don't really have a warm surface push coming in beyond maybe the very immediate coast since the ESE winds aren't especially strong and the water temps are about as cold as they get for the year. It'll be interesting to see how cold the south shore gets. Latest HRRR (admittedly might be a little too cold) has my backyard at 32-33 by 6z but Captree at 36. That'll make a big difference in terms of getting the snow to accumulate and keeping away any rain mix. Mid level warmth is a different story and we need the coastal low to take over as soon as possible so the mid level warm push stops and the surface winds veer to more ENE.

Down to 36 here.

Your area will be a good test case. If the ABE area goes to sleet fast or can't accumulate, NYC and LI won't either most likely. NAM is concerning but hopefully a bit too warm.

Hopefully. Depends on how heavy the snow comes in and can stay, and how much the warm easterly winds warm up the surface. Usual caveats being on the south shore. If we see large breaks in the snow, that’s where the mid level warmth will also have an easier time getting in.

If it’s moderate or better it will accumulate. Temps will wetbulb down and it will be dark.

HRRR still looks good away from the immediate beaches. Hopefully by now that’s meaningful.

We should start dropping off soon with the sun going down and with any kind of decent precip rate we’ll wetbulb down. Real question is if coastal areas can get down to near freezing too.

Euro once again too cold in a SWFE 2 days out but hopefully the front end thump idea happens.

So far I’m glad the 12z models got a little more encouraging but it’s a nowcast situation with this IMO. Hopefully we don’t see the sleet line racing north tonight.

HREF essentially a carbon copy from 0z-4-6” for most of the city and LI, 2-4” extreme S shore, 6”+ for most north of the city. A little surprised. Hope it’s right.

It’s maybe a little better for the immediate coast since winds veer more easterly then ENE into the event but if the snow breaks up, could be dealing with 35-36 and trying to restart the snow/accumulate which will be very hard. Eventually warm mid level air probably will make it in which means it goes to sleet or more likely rain. That’s why these maps showing the N to S shore accumulation contrast make sense. On the N shore and just inland temps are near freezing or a little above which makes accumulating a lot easier.

It’s why I haven’t even commented on this storm yet. It’s impossible to be excited about anything more than 4-5 days out. Maybe the confluence can press it south but the SE ridge is going to try and make it cut. I plan to enjoy whatever falls tonight/tomorrow and hopefully at some point by the end we can get a little more.

Held steady. Hope it’s right.

Your dew point is 18.5 so when precip comes in it will cool down quite a bit.

Another reason we want the snow/precip to come in like a wall.

I don’t think rain will wash away what falls at least away from the Rockaways. Might change to rain but 2 or 3” will stick around into tomorrow.

Has more of a front end burst which helps a good amount. It still warms up the mid levels overnight and flips us to sleet. But after a few inches falls already.

Hopefully you’re right and it would also help keep the warm air at bay for a while.

If it totally covers the grass I’d call that something of a win. When we see these warm layers start showing up in a SWFE they 95% of the time happen. And at least sleet lasts longer.

The Euro might be too cold in a situation like this with strong WAA. Hopefully I’m wrong. It’s pretty likely at this juncture that at least NYC, LI and maybe close to I-80 get scalped for a while. Hopefully it doesn’t shave too much off but the NAM would probably be mostly sleet on the north shore and sleet to rain on the south shore.

NYC finished with 5” or so in 97-98 not 0.4”. The all time record is 2.8” in 1972-73 which would still be in danger if NAM is right.

Yeah if we get a shredded up initial burst, the sleet line will race north and we'll accumulate less anyway. If it comes in like a wall it will fight back the warm air for a while and accumulate faster. I'm never ever optimistic about SWFEs here as you can tell, but we do get the ones that can snow here every few years or so. It's been about 4 years since the 11/2018 good bust...

It has a nasty warm layer around 800mb overnight. It's worse than the other models but it'll likely be the closest to correct. NYC and my area at least would definitely be sleet on that and the south shore and East Brunswick area etc would probably just be rain. You're likely good.