eduggs

Sign me up for the 12z GFS. Some snow to long duration frozen mix. Nice trof axis and pretty cold surface. But unlikely outcome.

12z GFS is pretty interesting around the 10th. That would probably work. But it's a long way off and too much run-to-run variability to have any confidence. The threat for the 8th keeps decreasing in likelihood.

Is that persistent band near Franklin County Airport in Vermont typical with these setups? It looks like some Lake Champlain enhancement from the Ontario LES band. The low elevation also probably enhances the reflectivity relative to the terrain due to better line-of-sight. I feel like I've seen that feature before, but I don't usually look carefully for it. There doesn't seem to be any mention in the NWS BTV forecast. Kinda cool.

Well first week and probably into second week of December looks below normal. And you have to weigh the nearer term more heavily based on lower forecast skill in the long term. The second half of December could be average to slightly above and you'd still end up with that monthly temperature forecast in the northeast.

18z GFS is a sweet run for coastal Maine and SE NH and pretty intriguing for EMA and the rest of New England for the Dec. 8th potential event. Too late for us. But it demonstrates potential for rapidly translating a flat mid-level shortwave into a deepening cutoff with SLP capture. Eastern New England is clearly favored and there still isn't much inter-model support, but at least it's something to watch.

Me too. I think north of I-287/I-80 has a 50-50 shot at 1". South of there will be tough. We're going to need some luck.

We need more STJ involvement. Or we need a ridge axis further west with the s/w for the 8th diving further southwest. As is, the modeling is not close. Any cyclogenesis would happen too late outside DE Maine and the Maritimes. If the STJ links with the follow up wave around the 10th, chances increase for rain. Low expectations are advised for now.

12z GFS and CMC not very good. Still barely trackable threats. The lead up to the elevation event a week ago that delivered accumulations to southern Westchester was far more interesting.

Winter is too short for patience. We will only have a few windows of time where we can get snow locally. Treasure every snow shower.

Rain

The next 10 days looks to favor New England, and Maine in particular if ensembles are to be believed. Positive 500mb anomalies make it as far east as MN, which creates a steep NW flow angle that doesn't usually deliver us much precipitation. Maybe something changes moving forward. It wouldn't take too much to get some snow showers at least. Web cams from ALB to Glens Falls look nice today. But it always seems like it's snowing somewhere else.

Yes we all agree 10:1 is arbitrary. But if a chart specifically defines the output as representing a 10:1 liquid to snow ratio, the model just needs to get the ptype and QPF correct. The snow map is just a visual representation of data... like a graph or plot. It's not a forecast.

A factor of 2 is a big difference IMO when people still post SV maps on this board and then you start referencing those maps. Go check how StormVista compares to Pivotal or TropicalTidbits or whatever others are out there in terms of snowfall. Yes 10:1 is an arbitrary starting point. But if you don't get that part right, your starting point makes it hopeless to even be in the right ballpark.

You and your dumb ass buzzer are confusing yourselves. Whether a 10-1 ratio is correct is irrelevant to the point. When a snow map shows "total snowfall at 10:1", the primary model parameter in question is QPF, not accumulated snow. The secondary model parameter, which is often calculated by 3rd party algorithm, is ptype. If a model correctly predicts QPF and ptype, a snowfall map that multiplies liquid equivalent by 10 and displays it as total snowfall at 10:1 would be absolutely correct. It just might not be an accurate prediction. Some 3rd party maps do this task pretty well. StormVista does not.

Obviously all snow maps are coarse approximations because many factors affect snow accumulation. But some algorithms are semi-accurate at identifying ptype under most conditions and then multiplying QPF by 10. StormVista is different. It will show 4" of snow based on 2 tenths of liquid and a min temps of 37F. StormVista snow maps are garbage and distinctly worse than most other maps. This is a relatively simple and hopefully non-controversial point.

No. Some snow accumulation maps accurately convert modeled liquid precipitation to snow at a 10:1 ratio. StormVistaWx does not. So it's in a different category altogether from other so called clown maps. Hopefully this is understood when people consider what they would take in terms of fantasy snowfall.

1. Most of the ens modeled snow comes in weenie range outside of NNE. 2. StormVista snow maps are inflated by approx. a factor of 2.

It will be difficult to get more than a tenth of an inch liquid out of any of those. And the GFS still has ptype issues for the immediate coastal plain. But still an entertaining run. The CMC has a less favorable trof angle with the ridge pushing further east giving us more of a NW flow instead of WNW on the GFS. Subtlety in the evolution and progression of the shortwaves will determine if we can score an inch or two of snow over the next 7-10 days. There should be at least a few periods of snow showers, possibly even lake-effect streamers. It's nice to have some coldish weather. But no significant storms on the foreseeable horizon for now.

The 12z GEPS likes Dec 5-6 for a potential coastal storm - miller B style. GEFS and EPS have a weak signal there too, but nothing exciting. Cold and dry after Thanksgiving until further notice but enough interest to keep checking model runs.

It was elevation dependent in that area. 6"+ in all direction from Walt D, including east and south, above 1100ft.

Based on the OKX PNS, it looks like those areas did pretty well, even below 800ft!! Good start to winter! ...Orange County... Port Jervis 12.8 in 0630 AM 11/22 COCORAHS 1 WNW Monroe 8.2 in 0700 AM 11/22 Trained Spotter Chester 8.2 in 0815 AM 11/22 Trained Spotter 5 N Port Jervis 7.4 in 0530 AM 11/22 Public Warwick 7.2 in 0700 AM 11/22 COCORAHS Warwick 3.9 W 7.0 in 0600 AM 11/22 COCORAHS 0.8 N Port Jervis 4.0 in 0700 AM 11/22 COOP

Modeling was fairly accurate IMO and the weather gods delivered! Also good call by you if I remember correctly.

Overall I thought guidance performed very well for this storm. The complex synoptics were well modeled by midrange guidance and the thermals were fairly accurately depicted by mesos and even midrange with hi-res thermals. Models correctly predicted the major snows in elevated parts of Sussex, the snow into lower Westchester, the approx. snow line at 700ft or so, and even flakes in the air for much of the region. When the model output shows a snow event, IMO it's a good idea to believe it... especially when you have inter-model and multi-model support. I know in previous decades it was unpopular to practice so-called modelology, but weather models have come a long way. Medium and especially short-range models are pretty accurate. Despite this event being well-advertised, it still seemed to sneak up on some people. Welcome to winter!

Driving around NE Morris County... couple observations: Slushy accumulations began at about 600ft and rapidly increased above 1000ft. No acc. at 500ft Coating at 600ft 1" at 750ft 2" at 900ft 6" at 1100ft

On radar it looks like heaviest bands will be shifting towards the NJ-NY border area into SENY over the next few hours. The SLP is pretty far east.