2-5

2/4 As I type, snow is observed in Caldwell ,Teterboro, NYC and White Plains.  But just plain rain here.  We had snow radar returns from 9am to now at 2pm, but didn't make the ground.  Dew point is up above freezing now so evaporational cooling will not help. Areas in PA are getting a good on though.

2/2  Two camps on this one.  GFS/NAM current camp is all the energy and focus on the clipper through the lakes and just a frontal passage for us.  Perhaps some front end snow, not depicted here, but usually happens.

Vs the Euro/CMC camp where the clipper dies off and transfers energy to the southern system.  This is also a common solution.

Right now, neither solution brings much in the way of snow to the immediate area, but the cmc/euro solution could change that very easily, and does bring snow to the Poconos, Catskills and Berkshires.

I'm not sure where the NWS is getting their current forecast.  They have 20% chance of snow Saturday night, Snow all day on Sunday with 1-3 inches, and Sunday night turning back to snow with additional 1-3 inches.

The last two runs of the SREFs are under an inch, while yesterdays 21z and todays 3z runs are  2.5 and 3 inches.  Maybe its based off the SREFs.  They don't mention the source of their forecast in the AFD, just that inland areas could see 1-4 and up to 6"



1/31

This looked like a great opportunity yesterday. However, todays trends are to bring it too close to the coast for all snow. Most concerning is the NAVGEM which trended further west all day.

GFS is also trending west with precip

EPS showing large spread

ICON with a warmer storm, though low placement suggests otherwise, plus there were front end snow.

And the CMC

Its a little complicated - I'm 50% total snow for Northern Fairfield to 50% mix right now.  I think things are leaning towards a mix though.  Coastal areas definite mix, though snow could still accumulate.

Swings and misses

1-29  This mornings GFS run shows the precariousness of a weather forecast.  Yesterday all these storms brought snow.  I'm calling the #3 and 3.5 a miss because they were supposed to combine, and still may.

Miss 1 - today

Miss 2 - Feb 2

Miss 3 OTS

Miss 3.5  - Should have merged with 3

Miss 4 - another case of energies missing each other

Miss 5 - not really our storm

Miss 6 - way out there.

Groundhog day

2-2 Results.  Despite it getting down to the 33 degree mark around 7pm, it took until about 1:30 to change to snow.  It seems like there is a layer of ice, sleet, then crunchy snow everywhere.  Schools delayed.  Measured just under a half inch, close enough to call it that as it didn't get into the sleet layer much.
 Picture of radar at 1:30am

 Flurrying out as I type.  The NW corner got 2-4 inches

1-30  Still looks more like a frontal passage. The 700mb vertical velocity is pretty impressive though the boundary layer is warm south of NYC  From GFS - could be good quick dump either rain or snow.

NAM is a bit more optimistic

CMC not so much

Euro puts down .2 qpf on its text, with 850s supporting snow and sfc temps 1.6c to -2.8C







1-29 This is becoming more of a frontal passage situation.  The odd thing is it may end up being anafrontal, precip coming in the form of snow after the front passes as the trough tries to go negative, bringing moisture up the backside of the front.

What we need to watch is that a low doesn't pop off NJ right before this, not to dissimilar from todays situation with a wave riding up the front.  This is demonstrated by the ICON model

1-27 So like the storm a few days before this, another frontal passage with a wave of low pressure moving up. Not too much time for analysis, but here are some pics for the record.  Looks like a minor event today, not so the previous days on the GFS.  So something else to watch.  Also the 6th?

yesterdays jma

1/27 evening - NAM trending?

1/28 - 1/30

1/30 results - no model got this right consistently.  Indeed it was a coastal scraper, with snow totals in the Trace to 1" range NYC and west.  East of NYC different story with totals 2-4 in Nassau and Fairfield, 4-5 in New Haven, 3-9 in Suffolk, 5-7 in Middlesex and New London.  Jersey Shore saw 2-3".  SE Mass saw up to 8" as did RI. These were the snow maps from 0z

1/28 morning  Front is passing, still like the idea of scraping the coast.

NavGEM

 NAM still just nicks ACK and the Cape

CMC a little wider with precip

GFS with my idea

Again, just a T-2" for coastal, perhaps 2-4 at the Cape.  0-2" inland, with ULL snow showers included. 





1/27 morning

Still at the 50% coastal scraper (.05-.25 qpf coast/.05-.1"qpf inland) 35% out to sea and 15% inside BM/hugger.  Some of the models have switched around and as energy gets ashore as I type I'd expect changes. Focus remains LI,SECT, SEMA to Maine.  NJ/DE/MD/VA may also get scraped.  Not getting into the snow showers from the trough coming through or any inverted troughs, other than to say there will be some.

So the NAM came into range yesterday with two very out to sea runs.  Today's 6z run had the idea of scraping the coast with LP around 68W

12z further east around 66W - still counts as a scraper since the cape gets some precip

GFS which has shown the idea of a coastal grazer for most of its runs is at 6z similar to the NAM at 66W.

Euro which had been the only out to sea model for the last few days went to coastal scraper  yesterday, now is borderline out to sea again.  Looks to be around 65W

6z NAVGEM logically placed where it should be, the furthest east (note the Euro is really close)

And then there's these which show a real storm for most of the area east of the DE river.
The Icon which takes it to 67 W but has a wide precip field.

UKMET

And the JMA

I've said this for other storms...models should line up in following order west to east:  NAM/UKIE/Euro/GFS/NAVGEM but now its UKIE (68ish)/GFS(67)/NAM(66.5)/Euro(66W)/NAVGEM(65W)

So keeping the same call - and also looking at a storm for the 2nd.




1-26 Leaning 50% coastal grazer, 35% out to sea complete miss and 15% coastal hugger/inland

Euro is still a miss.  EPS really slowed down its trend west.

GEFS still coming back

Meanwhile in operational land
12z ukie looks like a coastal grazer

18z icon  - Icon has had this for many runs now.

JMA looks good - bombs

And the gfs still supports my idea

as does the CMC

1-25

Picking up from the last post today.  Number of models are showing the potential for some snow.  There are red flags for this everywhere, but I decided to open a post on it even if it whiffs out to sea.

Basic set up is that a disturbance in the gulf, south of AL, triggers a low pressure that rides up over or just east of the outer banks.  From there it moves somewhere between the benchmark and 40/65.  All modeling shows this.  Differences are a benchmark or east of benchmark path, and strength.  The differences are due to how much energy gets into the trough, how deep the trough digs and the position of the ridge out west.  All of these have been moving towards a bigger storm, at least as of 0z.  The trend this year is for these storms that look out to sea to come back west as more energy is sampled out west and input into the equation.  The exception was New Years when a monster high was coming out of Canada and suppressed the entire flow.  So for now I'm leaning towards a low impact system grazing the coast as 50%, an out to sea solution at 40% and an inland system at 10%.


UKMET is a little too east and weak.

ICON puts a double barrel low out there, just SE of 40/70 BM

GFS is also just east of the 40/70 - GFS is rarely the furthest west

NAVGEM, usually the furthest east, is at 39/69. Indicating other models are too far east.

The furthest east looks to be the Euro - it passes 40n at 66w.  The red flag here is that the Euro is not usually the furthest east.