Extreme Cold, Snow & Sleet: SECS 1/24 - 1/26

[SACRUS]

[Winterweatherlover]

GFS went from the coldest/snowiest model all week to now one of the warmest models.

[nycsnow]

Gfs has a snow hole over NYC like Ukie 

[SACRUS]

[nycsnow]

Pretty bad & now the GFS is on its own 

[jm1220]

1 minute ago, SACRUS said:

Looks lame/warm again like 12z. If we’re punching sleet up to I-84 here, people near the coast might barely eke out a warning event. Hopefully tonight 0z we resolve this one way or another, if not we watch the radar in the morning to see how the snow advances in. That’s really the difference maker here. 

[MANDA]

Just now, SACRUS said:

Based on most guidance going to see intense rate of snowfall from roughly 11am through 4pm along and north of a TTN to Sandy Hook to Montauk line from SW to NE.  The bulk of the snow is going to fall during those roughly 5 hours.

[nycsnow]

Just now, jm1220 said:

Looks lame/warm again like 12z. Hopefully tonight 0z we resolve this one way or another, if not we watch the radar in the morning to see how the snow advances in. That’s really the difference maker here. 

Shouldn’t we be putting less thought into these models and focusing more and meso

[nycsnow]

The gfs snow map don’t even make sense?? It’s not like there wasn’t snow or precip falling over the metro 

[wthrmn654]

As one of the NWS mets just told me, in regards to the nam. 

 

That degree of warming aloft might not be wrong. European seems slower to bring it in though. See what I wrote above about snow falling down south in some places where sleet was expected, don't know if that idea will work out east of the Appalachians as dynamic cooling from strong lift when the heavier snow falls here could delay any change to sleet and keep it farther south

[SnoSki14]

2 minutes ago, Winterweatherlover said:

GFS went from the coldest/snowiest model all week to now one of the warmest models.

Which should tell how of crappy it really is.

Also crazy how SNE could score 2'+ amounts with this when they thought it was gonna be suppressed 

[psv88]

I don’t see orient getting 12” and the city 3” in this setup 

[jm1220]

1 minute ago, nycsnow said:

Shouldn’t we be putting less thought into these models and focusing more and meso

Starting to get to that point but I’d say tonight we pay more attention. In any event we’ve seen the HRRR gradually getting warmer although still impressive at 18z. 

[MJO812]

2 minutes ago, nycsnow said:

The gfs snow map don’t even make sense?? It’s not like there wasn’t snow or precip falling over the metro 

It has a weird dryslot 

[nycsnow]

1 minute ago, jm1220 said:

Starting to get to that point but I’d say tonight we pay more attention. In any event we’ve seen the HRRR gradually getting warmer although still impressive at 18z. 

I mean I’m sure hrrrrr will fluctuate run to run but it’s been pretty locked in. Nam and gfs by far have been moving around the most of any suite  

[danstorm]

This is BARELY sleet (GFS sounding near me) and likely snow/sleet… with heavy rates it’s probably snow 

This is not the kind of storm that flips to sleet and done, that’s why I think my 8” call here may be low… I had 4/5 inches after mixing with sleet in Mar 2017 and this could be similar 

[jm1220]

Just now, SnoSki14 said:

Which should tell how of crappy it really is.

Also crazy how SNE could score 2'+ amounts with this when they thought it was gonna be suppressed 

The nature of this storm is pretty clear that New England would get nailed a few days ago. It was pretty clear to everyone this wouldn’t end up a VA/Mid Atlantic snowstorm. Retreating high, retreating confluence, trough in the west and SE ridging=SWFE that favors I-90, Boston over to Albany and S NY. The initial high pressure/overrunning gives people like us down to DC a fighting chance but the best is along I-90. I-84 should do very well too. 

[wthrmn654]

5 minutes ago, psv88 said:

I don’t see orient getting 12” and the city 3” in this setup 

Don't forget orient is farthest north versus the city or the island but yeah that is wonky 

[binbisso]

5 minutes ago, psv88 said:

I don’t see orient getting 12” and the city 3” in this setup 

Or dc 7" Philly 6" and nyc 3.5". Gfs should be retired

[EasternLI]

I think this is closer to reality from that run

 

[wthrmn654]

1 minute ago, EasternLI said:

I think this is closer to reality from that run

 

Yeah, where long island or cap cod doesn't even exist.  

[NJwx85]

4 minutes ago, danstorm said:

This is BARELY sleet (GFS sounding near me) and likely snow/sleet… with heavy rates it’s probably snow 

This is not the kind of storm that flips to sleet and done, that’s why I think my 8” call here may be low… I had 4/5 inches after mixing with sleet in Mar 2017 and this could be similar 

Couldn’t agree more. I think the heavier rates will help to overcome the borderline mid level warming. The charge to sleet probably only happens once a majority of the precip has already fallen, sometime after 02-03z.

[Prue11]

NOAA has me getting up to 32 degrees tomorrow for a high. 

[donsutherland1]

Prior to the warming of the mid-levels tomorrow afternoon, soundings showed a strongly saturated dendritic growth zone (DGZ) between –12°C and –17°C. That is almost ideal for producing large, fluffy dendritic flakes. There was also strong lift and high saturation supporting very efficient snow growth and high snow-liquid ratios, especially in areas with stronger banding. In short, for 3-4 hours there could be snowfall rates of 1" per hour and perhaps 2" per hour at times. That's when most of the snow will fall in and around New York City. The visibility could fall under one-quarter mile during the periods of heaviest snow. Thundersnow seems unlikely in most of the area as there isn't a convective signature in the soundings. 

It is these dynamics, not 10:1 snow-liquid ratio maps that tell the story of what continues to look to be a significant snowfall in and around New York City. On account of the system's dynamics ahead of the changeover to sleet and the storm's forecast QPF, I have little reason to deviate from my thinking based on today's 12z and early 18z guidance. 

Through early portion of the 18z cycle, it appeared that even as differences persisted among the guidance, the models were slowly moving toward a consensus with the exception of the 18z GFS. As 100% of individual EPS ensemble members from the 0z and 12z cycles had 6" or more snow, the 18z GFS's < 4" figure is not within the realistic range of possibilities. The strong dynamics noted earlier also suggest that the GFS's solution is unlikely.

Overall, a reasonable low-case snowfall for New York City remains 5". A reasonable high case is 12". 

New York City and nearby areas remain in line for 6"-12" of snow and sleet. Areas to the south and east of New York City could see 4"-8" amounts (even farther south beyond the New York City area, places like Atlantic City should see 3"-6"). General 12"-18" amounts are likely well north and west of New York City, most likely in parts of northeastern Pennsylvania (Pike County, Lackawanna County), Orange County, Dutchess County, Sussex County into at least the northern half of Connecticut.   

For perspective, the last time New York City saw a 6" or greater snowfall was January 28-29, 2022 when 8.3" fell from a rapidly deepening blizzard that buried parts of Long Island into southern New England under two feet of snow. Its last 10" or above snowfall occurred during the long-duration January 31-February 3, 2021 snowstorm when 17.4" accumulated. 

Up in southern New England, Boston appears on track to see 14"-20" of snow. If so, that would be that city's biggest snowsorm since the January 28-29, 2022 blizzard, which dumped 23.8" of snow. 

[NJwx85]

1 minute ago, wthrmn654 said:

Yeah, where long island or cap cod doesn't even exist.  

cap cod sounds like an elegant fish dish.

[SACRUS]

 

21z rap

snow between 2 - 5 am sunday

 

 

 

 

 

 

 

[NorthShoreWx]

1 hour ago, Rjay said:

19 and sleet lol

 

I'm not sure everything melts in that melt layer.  50mb is enough, but it looks like no more than 1⁰C.  OTOH, I'm not sure how much is even falling into that layer.  I'm thinking that's a mix, including some fairy crappy snowflakes from below 775mb.

[NJwx85]

Just now, SACRUS said:

 

21z rap

snow between 2 - 5 am sunday

 

 

 

 

 

 

 

Most of what falls before sunrise is probably virga.

[EasternLI]

Just now, wthrmn654 said:

Yeah, where long island or cap cod doesn't even exist.  

Well the GFS doesn't see us as important enough to include in the country so we have to extrapolate.

[jm1220]

3 minutes ago, binbisso said:

Or dc 7" Philly 6" and nyc 3.5". Gfs should be retired

It has crappy resolution which results in the weird snow map outcome but it doesn't have a heavy consolidated snow shield like the RGEM group does. Has an inch per hour maybe which is moderate snow.