NYC/Tri-State Area: Stumbling into January Disco

[earthlight]

The holiday weekend behind us, it's time to look forward to the next several weeks which will bring us into the heart of winter. Here we go boys and girls..

[earthlight]

There is some quickly growing support amongst the GEFS for a very anomalous ridge near the Rockies at this time. Although the NAO state is not favorable I wouldn't say we can write off some frozen precipitation if we can time a shortwave well. That ridge position usually means things will at the very least get interesting around here. Also notice the bucking heights near Newfoundland on the ensemble mean 500mb spaghetti plots. Indicative of the fact that if this event occurs, we'll be closely watching an event a day or two prior to it for it's effects on the pattern thereafter.

[Hailstorm]

I agree with what you stated, but I don't like the fact that the GEFS looses the warm North Pole anomalies when it had them in prior runs. Also, on that map, there is virtually no cold anomalies in Eastern Siberia or Eastern Asia; so a -WPO cannot form. The lack of a highly amplified Aleutian ridge on that map also does not allow a good -EPO to form.

[earthlight]

I agree with what you stated, but I don't like the fact that the GEFS looses the warm North Pole anomalies when it had them in prior runs. Also, on that map, there is virtually no cold anomalies in Eastern Siberia or Eastern Asia; so a -WPO cannot form. The lack of a highly amplified Aleutian ridge on that map also does not allow a good -EPO to form.

Well that is only 156 hours so we aren't going out very far in time when you're looking at that map. Things are still changing on the 00z GFS, which oddly enough actually trended more favorably with the 1mb warming (if we're on the topic of a pattern change). It remains to be seen how the downwelling will occur but 51 C I believe was the max near the pole. Now, it's still pretty cold on our side of the pole and at that point hasn't begun to change the pattern at 30mb so we are still a ways away, but it is definitely a start.

Synoptically, the GEFS actually show a half-decent pattern rolling towards the end of the run. Nothing to write home about, but not quite as bad as what we're experiencing and have been for the past several weeks. To see a weak ridge on the West Coast and some positive height anomalies in the vicinity of Greenland is a welcomed sight.

[TheTrials]

Well that is only 156 hours so we aren't going out very far in time when you're looking at that map. Things are still changing on the 00z GFS, which oddly enough actually trended more favorably with the 1mb warming (if we're on the topic of a pattern change). It remains to be seen how the downwelling will occur but 51 C I believe was the max near the pole. Now, it's still pretty cold on our side of the pole and at that point hasn't begun to change the pattern at 30mb so we are still a ways away, but it is definitely a start.

Synoptically, the GEFS actually show a half-decent pattern rolling towards the end of the run. Nothing to write home about, but not quite as bad as what we're experiencing and have been for the past several weeks. To see a weak ridge on the West Coast and some positive height anomalies in the vicinity of Greenland is a welcomed sight.

that looks like a late blooming Miller B pattern to me which can be OK for the city north and east.

[TheTrials]

gfs follows the euro with the new years eve clipper and actually gets it going a little off the coast. Surface is still warm but thicknesses and 850 are good. I'll check the soundings now,.

[supermeh]

gfs follows the euro with the new years eve clipper and actually gets it going a little off the coast. Surface is still warm but thicknesses and 850 are good. I'll check the soundings now,.

Definitely more euro-esqe

[TheTrials]

Yeah, surface is warm but there is room to wetbulb with a dry airmass. Just need more precip and lift.

[supermeh]

Yeah, surface is warm but there is room to wetbulb with a dry airmass. Just need more precip and lift.

Trough axis looks like it is going negative a bit too late. If we can get it to dig a bit more it might turn into something.

[Weathergun]

I would pay more attention to forecast low-level temps than the 850mb temps, over next 7 days or so. The antecedent airmass for each system that pass through, rots quickly.

[earthlight]

I still think the threat for a larger system exists around January 3rd through the 5th. Forecast models are still wavering on the potential development of a large ridge near the West Coast of the United States, which would find itself positioned near the Rockies around the 2nd of the month. The exact positioning and amplitude of this feature are big wild cards in the threat development, of course. Ultimately the lack of NAO support or any semblance of high latitude blocking will hurt us no matter what, as any frozen precipitation will likely changeover (or for interior spots, come dangerously close to doing so). Still, the potential for a fairly dynamic system does exist. The GFS has trended more amplified with the aforementioned ridge feature while the Euro remains by far the most amplified. It remains to be seen exactly how things will play out, but when you look at last nights Euro you can see that the models are definitely trying to catch on to the potential for something big in this time frame.

[ag3]

12z GGEM is more in line with the Euro for the day 8 storm. UKIE is flat like the GFS and has the ridge axis way east.

Here is the GGEM:

[TheTrials]

cmc would be snow to rain to heavy snow in the next frame with gorgeous h5, h85, and h7

too bad its the cmc

[TheTrials]

kicker on the cmc helps too keeps the trough axis moving east so it doesnt cut

[Thunderdude]

I think the storm system next week will usher in the pattern change. We would want it to take the inland cutter track and then MJO phases so that would drop the NAO and start the blocking pattern. Then we could then be brewing something later on and probably the middle of January we could see our change for a coastal storm.

[Weathergun]

I still think the threat for a larger system exists around January 3rd through the 5th. Forecast models are still wavering on the potential development of a large ridge near the West Coast of the United States, which would find itself positioned near the Rockies around the 2nd of the month. The exact positioning and amplitude of this feature are big wild cards in the threat development, of course. Ultimately the lack of NAO support or any semblance of high latitude blocking will hurt us no matter what, as any frozen precipitation will likely changeover (or for interior spots, come dangerously close to doing so). Still, the potential for a fairly dynamic system does exist. The GFS has trended more amplified with the aforementioned ridge feature while the Euro remains by far the most amplified. It remains to be seen exactly how things will play out, but when you look at last nights Euro you can see that the models are definitely trying to catch on to the potential for something big in this time frame.

I think the snow potential is on the backside of this storm. The antecedent airmass is trending warmer. Interior areas have best shot of rain/mix going over to heavy snow.

[TheTrials]

LOL, CMC is pretty much a three stream phase with a piece of the arctic jet phasing with the split pac jet. Yeah, that's gonna happen

[earthlight]

I think the snow potential is on the backside of this storm.

I agree. There is a frontal boundary near the area on most models at this point which would likely buckle north and west for a time and then collapse south and east. If the storm is strong enough, everybody could change over to heavy snow for a while.

That being said, this is all heresay. We are still just seeing the first hints at this system from the guidance -- so it will be interesting to see where this goes over the next several days.

[Weathergun]

I agree. There is a frontal boundary near the area on most models at this point which would likely buckle north and west for a time and then collapse south and east. If the storm is strong enough, everybody could change over to heavy snow for a while.

That being said, this is all heresay. We are still just seeing the first hints at this system from the guidance -- so it will be interesting to see where this goes over the next several days.

Before, the models had a high over SE Canada. That could of been enough for at least inland areas to start out frozen. But now the clipper on New Year's Eve is trending farther south and weaker. There is just not enough confluence to support the high any where there.

[ag3]

Not one member of the 12z gefs has anything remotely close to the 0z euro or today's 12z ggem.

They are mostly all flat with a ridge well east of the east coast.

[IsentropicLift]

Before, the models had a high over SE Canada. That could of been enough for at least inland areas to start out frozen. But now the clipper on New Year's Eve is trending farther south and weaker. There is just not enough confluence to support the high any where there.

Not one member of the 12z gefs has anything remotely close to the 0z euro or today's 12z ggem.

They are mostly all flat with a ridge well east of the east coast.

The goofus was showing something in this time frame last week, then lost it. The CMC has a nice high over SE sliding east with the system.

The surface low gets pulled towards the coast east of the Delmarva, just as temps are crashing towards the coast. This would be a big hit on later frames verbatim

[bass28]

Not one member of the 12z gefs has anything remotely close to the 0z euro or today's 12z ggem.

They are mostly all flat with a ridge well east of the east coast.

Last nights ens had it cheese.

[ag3]

Looks like the euro dug the shortwave a little more and the clipper is stronger.

Anyone with the detailed maps, how do precip amounts look and surface temps?

[earthlight]

Looks like the euro dug the shortwave a little more and the clipper is stronger.

Anyone with the detailed maps, how do precip amounts look and surface temps?

Surface temperatures are warm and precip amounts are light to moderate at the very best -- it looks like a mostly light rain event with a few mangled flakes potentially mixing in at the end.

[ag3]

Surface temperatures are warm and precip amounts are light to moderate at the very best -- it looks like a mostly light rain event with a few mangled flakes potentially mixing in at the end.

Thanks.

[earthlight]

Monster ridge spike once again on the Euro at 126 hours. Looks, so far, to be a bit west for my liking....but it is an extremely anomalous feature -- especially in comparison to what we've been experiencing so far this winter.

[TheTrials]

Monster ridge spike once again on the Euro at 126 hours. Looks, so far, to be a bit west for my liking....but it is an extremely anomalous feature -- especially in comparison to what we've been experiencing so far this winter.

probably will look like CMC to some extent, its def. not aligned in a way that starts out well for us, especially with the +NAO from hell

[earthlight]

570dm heights now well into British Columbia at 132 hours.

[earthlight]

It is good to see the potential for a significant storm system once again on this run so far -- it looks like three or more runs in a row with this type of potential. Whether or not it gives us any snow, I think the potential exists for a rather dynamic event.

[Weathergun]

The goofus was showing something in this time frame last week, then lost it. The CMC has a nice high over SE sliding east with the system.

The surface low gets pulled towards the coast east of the Delmarva, just as temps are crashing towards the coast. This would be a big hit on later frames verbatim

The high comes in behind the cold front. We've seen this setup before. The southern branch speeds up and amplifies faster.