12z Model Thread 12/8

[Ridingtime]

It's definitely a nice trend and as earthlight said before, the most amazing thing about this is that its 114 hours away. If I were to learn anything from tracking winter storms the past 4 years, its to never really make any definitive conclusions that far out, and I should not have given up on this thing yesterday so fast.

On the other hand, this is a thread in the needle situation. The good components of a snow storm are still missing thanks to the lack of blocking, high to the north, good 50/50 etc. So while I am inclined to hope for some snow, even if its just some backend stuff, I'd encourage everyone (including myself) to not create too much expectations just yet for this thing.

[earthlight]

12z UK is further east of it's 00z position from what I can see

[phlwx]

Sure, that could definitely help our cause. Also if the polar vortex was positioned further southeast, and the wave was less amplified we would be in much better shape too, even without a 50/50 low or the classic setup. But this would have to be pretty substantial even at 114hrs out. There is no avoiding the screaming east/southeast winds at the start of this thing in my opinion. 2nd half of the storm is still up for grabs though I'll admit.

Yep...it's not ideal. However, you folks up there and the folks in Allentown stand a much better chance of getting thumped on the back end of this storm with a nice round of snow if this is the final solution. If the trend east continues things may change altogether...

[The Iceman]

12z UK is further east of it's 00z position from what I can see

wow and wasn't the UK the farthest east as it was?

[cleetussnow]

Now that is incredible. Seriously, what is their record snow depth?

probably like 4-5 feet. Fulton is going to be the ridiculous one at this point.

[bluewave]

GFS raw numbers take NYC down to 13 degrees by 144 hrs.

[Chris L]

Also its the GFS, the suckiest model on earth IMO haha. Hoping to see the Euro hop on board soon.

Well, come on. GFS is miles better than the NOGAPS, KMA, JMA and slightly better than the GGEM.

[NJwinter23]

NYC might get to about 8 in that during December...the calm winds are the problem there....the coldest nights there will happen with strong cold advection with a 20 mph wind.

Yup, though ironically it is looking like we will have a strong caa pattern inside the pressure gradient behind this storm, bringing in -20c air possibly at 850. Though if we thought we were getting ahead of ourselves with this storm 160hrs out, same goes it for the strength of the cold shot behind this storm.

[KEITH L.I]

http://www.nco.ncep....fs_pcp_384l.gif

Christmas Eve.

one thing you can say, with that block in Greenland we will be below average temps wise during Christmas week.All we need is a decent storm track for a white Christmas

[eduggs]

This GFS run clearly salvages hope if not a little snow, but it's still not very good for the cities - especially NYC - unless you're just hoping for short term cold. By the time NYC cleanly switches to snow, the surface low is nearly to VT. Western areas would do better of course. But model output notwithstanding, this does not resemble a favorable wraparound scenario through the metro corridor.

We need to parlay this into an inter and intra model SE trend.

[tombo82685]

here is the gem at hr 84, 0z sunday looks to be a little further north than the gfs

[Ridingtime]

Well, come on. GFS is miles better than the NOGAPS, KMA, JMA and slightly better than the GGEM.

Point taken, but I feel we use those models more in desperate situations, whereas wde are always checking the GFS. And because of that, it is more frustrating when it continues to be a model that flips back and forth so often from solution to the next, even when the storm is a day away.

[eduggs]

NYC might get to about 8 in that during December...the calm winds are the problem there....the coldest nights there will happen with strong cold advection with a 20 mph wind.

Well this could very well be the case for the City. I think anything below 15 is pretty good for this time of year (in modern times anyway).

For me in a sheltered valley to the north, downsloping winds off the Catskills don't seem to help the cause. Calm seems to work best up this way.

[tombo82685]

here is the gem at hr 96, obviously diff than the gfs, but it looks like its devloping a new low over the carolinas or something with all that precip breaking out down there

[earthlight]

The Ukie has been east for several runs now...and it looks like most guidance is showing some semblance of a trend in that direction. So it will be interesting to see if the Ukie can score here.

[Quakertown needs snow]

Man who ever gets a snow pack could have record lows

[Sundog]

What is the actual track on the UKIE? I am not familiar with the track it had on the previous runs either so I would not be able to gauge the level of improvement when told only about the 12z run's position.

[eduggs]

Well the Canadian won't make us throw a party. And run to run changes are always far more complex in nature than given credit for. But I'll commit the error anyway and simply say that at quick glance it seems slightly more favorable leading in.

[SnowGoose69]

Man who ever gets a snow pack could have record lows

Syracuse reached -15 to -25 several times in December 89 which was their snowiest Decmeber on record before 2000, 2002, and 2003 LOL.

[NJwinter23]

here is the gem at hr 96, obviously diff than the gfs, but it looks like its devloping a new low over the carolinas or something with all that precip breaking out down there

That's just the warm front I believe, the kinks in the isobars.

[NJwinter23]

Man who ever gets a snow pack could have record lows

meh...too much of a wind factor going on between the departing storm and the HP.. At least when our 850s bottom out.

[SnowGoose69]

Well the Canadian won't make us throw a party. And run to run changes are always far more complex in nature than given credit for. But I'll commit the error anyway and simply say that at quick glance it seems slightly more favorable leading in.

The GEM has done this before having one of the warmest or furthest west solutions....it doesnt mean its wrong this time but its suspect to me with almost everything else recently going east.

[Quakertown needs snow]

meh...too much of a wind factor going on between the departing storm and the HP.. At least when our 850s bottom out.

yea forgot about that factor... to many isobars

[tombo82685]

here is the gfs ens mean, looks like its the same as 6z maybe a little further east

[earthlight]

12z GFS Ensemble mean takes the low from ACY to Southern New England..988mb. 120 hours the low is south of Long Island. A smidge east from the OP still.

[NJwinter23]

The GEM has done this before having one of the warmest or furthest west solutions....it doesnt mean its wrong this time but its suspect to me with almost everything else recently going east.

Agreed, the GGEM being the warmest/west solution is hardly a surprise..That's not to take away that I believe this will still be mostly a rainstorm for the big cities. We'll see if the changeover idea can build some steam, I'm really hoping so.

[earthlight]

GFS Ens means close the H850 low south of PHL...while the OP has the 850 low closed in Northeast PA.

[Chris L]

GFS Ens means close the H850 low south of PHL...while the OP has the 850 low closed in Northeast PA.

That is actually a very good sign because all significant snow events have a H850 closed low SE of PHL in order for PHL-NYC to stay all snow.

How does H700 look?

[LocoAko]

For its limited worth, this run of the GFS gives RUTG 1.00" of rain followed by 0.6" of snow accumulation.

[Kaner587]

back to the rich getting richer...syracuse has recorded a 4 day total of 56.2 in and its still snowing, with 6-10 expected today and another 6-10 tn. I was there 4 years and have been following there weather since I graduated and this is something I've never seen before. This is already roughly half of their seasonal avg (115in). Pretty incredible