December 26-27 Storm Threat

[cpickett79]

someone said after reading the OP gfs that they could see from WV that there was more northern stream digging energy headed down thru canada now.....and to the effect that this makes sense with 12z gfs op....do we toss this also.

[ORH_wxman]

someone said after reading the OP gfs that they could see from WV that there was more northern stream digging energy headed down thru canada now.....and to the effect that this makes sense with 12z gfs op....do we toss this also.

Being still 60-72 hours away, I think its way too early to tell too much from the water vapor loops. You might be able to tell if something is slightly off in one area, but we can't account for how much difference that will have when the complex phasing occurs. So yeah, someone could see the energy diving through Canada is pretty strong, but just how much does that affect the phasing potential?

[Typhoon Tip]

I don't know. If it's that big of a deal, why did the 00z GFS look so similar to this 12z run. Other than nit picking, the sensible weather difference between those to runs is negligible - both are solid clocking with similar deep layer features.

I just analyzed the field; I wish James would be more clear on "how" he is making that determination because from what I see those 'errors' seem exaggerated.

[CT Rain]

Well 150 miles would be pretty massive, but I said "shocked" not expected. Models work buy incorporating previous run's data so I'm not sure how valuable the 18z run will be.

Agreed.

[moneypitmike]

What did those look like?

I'm just catching up.

Why do people give a crap about the GFS ensembles? If the data was incorrect going into the model, why would you put any credence in the ensembles? Do they use a different data set? I'm puzzled.

[cpickett79]

well i'm not sure if this was copy and pasted but i do put faith in reading Don's thoughts for today

we will not like them (unless boston gets.....7 or more from this system ) putting them over 10 for the month.

Morning thoughts:

1) After taking some time to examine the synoptic pattern and having a look at some of the KU snowstorms for more ideal patterns, I suspect that a good idea for the range of solutions is between the 12/24 0z and 12/24 6z runs of the GFS. There is still a possibility of a solution outside those two, but the opportunity for that outcome is waning.

2) Translated into real weather, parts of New England have the best chance at seeing a 4"-8" snowfall with locally higher amounts. The Jersey Shore, New York City, and southwestern Connecticut have a decent chance of picking up 1"-3" maybe 2"-4" locally (farther east) but there is still an uncomfortably high risk of even lighter amounts.

3) The severe shot of cold shown at the end of the 12/24 0z run of the GFS does not fit the emerging synoptic situation from the Ohio Valley eastward. A more modest shot of cold is still possible there. Stronger cold is possible north of the Canada-U.S. border.

Disclaimer: Those who are faint of heart should stop reading here.

Ugly snowfall Statistics: ENSO Region 3.4 Anomaly -1 or below in both December and January

Boston:

December snowfall < 10": 6/7 (86%) cases had < 40" seasonal snowfall; < 10" December snowfall and no measurable November snowfall: 5/5 (100%) cases had < 40" seasonal snowfall

New York City:

December snowfall < 2.5": 9/10 (90%) cases had < 20" seasonal snowfall

Washington, DC (DCA):

12/12 (100%) of those La Niña cases had < 20" seasonal snowfall; 5/12 (42%) of those La Niña cases had < 10" seasonal snowfall

so don like's somewhere between 0z gfs and 6z gfs.....ok but ensembles were awful for 0z gfs ....even thou the op was good.

[DeVries]

After today, only one more week until 2010 is finally over.

Looks like I'll be able to drive out of Boston on Monday morning after all.

[Boston-winter08]

NAM can't come soon enough; i'm not giving up on this one, especially considering the last westward trend we saw with the most recent one

[Zeus]

Why do people give a crap about the GFS ensembles? If the data was incorrect going into the model, why would you put any credence in the ensembles? Do they use a different data set? I'm puzzled.

The post I was responding to was pointing out consistency in the GFS ensembles; I figured this was threading several runs together; I haven't been keeping up very much with this one.

Hence, if the 12z GFS ensembles from yesterday matched -- relatively -- the 00z ensembles and even the allegedly false as Hell 12z GFS vittles, I am curious as to what that broad stroke painted.

[cpickett79]

i hope the euro ensembles appear more amplified. read that the 0z euro ensembles went progessive last nite.

will be waiting to hear from them. 0z gfs ensembles were awful compared to the op.

[isnice]

I don't know. If it's that big of a deal, why did the 00z GFS look so similar to this 12z run. Other than nit picking, the sensible weather difference between those to runs is negligible - both are solid clocking with similar deep layer features.

I just analyzed the field; I wish James would be more clear on "how" he is making that determination because from what I see those 'errors' seem exaggerated.

Yea that's what I was thinking. But, that does not explain the misery euro

[ski MRG]

Why do people give a crap about the GFS ensembles? If the data was incorrect going into the model, why would you put any credence in the ensembles? Do they use a different data set? I'm puzzled.

Mike, c'mon man, weenies are just trying to find a reason to believe, regardless of how flawed the logic may be. We're still in the game BTW.

[Boston-winter08]

Thing is, in reality, the 12z run is not all that different from 00z...it just happens to suddenly shift a few degrees longitude to the west to suddenly affect millions more people down I-95, and all of a sudden question marks are raised...i'm not saying the 12z run is on to something, but there could certainly be some truth to it

Not to mention i could care less about the Euro's sol'n inspite of its successes last year

[moneypitmike]

The agreement between the GFS ensembles in mind boggling to me, initialization errors or not. Have never seen that! That tells me that at very least this is trending west. We still have 48h to trend this a little more west. GFS OP not out of the question but not likely either. EC op may be a wobble, have to wait for the ensembles.

That makes no sense. That's analogous to someone telling you a made up story that you think is try. Then have 9 people tell you a similar story. Just because more poeple tell you a fake story doesn't make the story and more real.

[Baroclinic Zone]

Mike, c'mon man, weenies are just trying to find a reason to believe, regardless of how flawed the logic may be. We're still in the game BTW.

You receive snow like 300 days of the year. Your odds of <4" are slim with this one.

[RICoastalMan]

Barring an Xmas miracle, I will always remember this as the holiday season with two:

[cpickett79]

weenies in SNE giving up at this stage is a coping mechanism so there not deflated when not much happens. it is based party off emotion and thus not helpful with accuracy

we saw last week that our fantasy thread was started with barely any model support (perhaps a couple gfs ensembles) and then it backed west anway and gave several parts of the cape a foot and the south shore and south bristol county a half foot. unless most ensembles take this out to sea.......it will be a now cast to a degree IMO.

[Typhoon Tip]

Yea that's what I was thinking. But, that does not explain the misery euro

I don't know about that either, the Euro still incorporates our input data into it's own assimilations/initialization

[MaineJayhawk]

18z American models will be flawed ... will be disregarding at this end. 0z will be very interesting.

Merry Christmas all.

[moneypitmike]

I'll take my 10-12" on that and run. ....actually I'll take 1-2" out of this thing.

People in southeast NE are getting a bit greedy, but maybe I would also. They are still well in line for 6" or more probably.

Even before this data debacle, the NAM's been consistent in giving me that. I'm clinging to the NAM--lol.

[CCPSUSuperstorm2010]

Not at all worried about today's 12z runs, I have confidence in my 35n/75w to 41n/69w low pressure track, low should be around 975mb as it reaches 41n/69w around Monday morning.

[Baroclinic Zone]

weenies in SNE giving up at this stage is a coping mechanism so there not deflated when not much happens. it is based party off emotion and thus not helpful with accuracy

we saw last week that our fantasy thread was started with barely any model support (perhaps a couple gfs ensembles) and then it backed west anway and gave several parts of the cape a foot and the south shore and south bristol county a half foot. unless most ensembles take this out to sea.......it will be a now cast to a degree IMO.

Giving up on what? Therein lies the problem. Never get yourself emotionally vested into one model solution. There is a clear consensus coming on board for this upcoming storm and it does not involve substantial snows for just about everyone except maybe CC.

[CT Rain]

I have to say... the Euro isn't all that far from the GFS.It closes off the 500mb low near Asheville, NC.... but it remains positively tilited. It's amazing that even with a much better phase the Euro is still east. Won't take much to get a more exciting solution than the Euro shows.

[Bostonseminole]

Not at all worried about today's 12z runs, I have confidence in my 35n/75w to 41n/69w low pressure track, low should be around 975mb as it reaches 41n/69w around Monday morning.

i hope you are right.. the 6hr 12Z gfs did not look that much different from the `18Z 500mb analysis real time analysis, but as Will said so many things need to happen for phasing to occur that may not matter at this point, but by tomorrow it will.

[TalcottWx]

Agreed.

I would toss the gfs solution at 12z, obviously. A disheartening sign from the euro earlier but is their data affected at all like the american's? That's the only question to be raised imo. If the gfs comes east at 18z and it incorporates previous runs we obviously know if the correct data is finally being ingested that the correct track right now is somewhere east of that. This all comes to the fact that the 12z gfs is horribly off and should be east of its 12z beast solution. There is the slight chance that the american models are correct and the hpc hooplah is all about nothing but LOL how much money would one want to bet on that? Take the people over the models and the weenies. I feel like confidence is still extremely low and we don't have a probable solution. I don't know how you would be able to be confident. All of the fllipping and flopping of the models in the last couple days and the horrible initialization errors that the hpc claims, wow. I still feel like we see a solution over or just outside the benchmark. Warning snows to BOS and I-95 and the Cape gets blitzed.

[Zeus]

I have to say... the Euro isn't all that far from the GFS.It closes off the 500mb low near Asheville, NC.... but it remains positively tilited. It's amazing that even with a much better phase the Euro is still east. Won't take much to get a more exciting solution than the Euro shows.

This is a storm I actually don't want, for selfish reasons.

I hope that little bit of magic it takes to get a blizzard simply buggers off this time.

[weatherwiz]

I think pretty much the only thing left to figure out is if eastern sections get moderate accumulations in something like the 4-8'' range or if there will be possible accumulations of greater than 8''. The signal is becoming a bit more clear of where this storm is likely going to track but with some minor adjustments to be worked out. Probably the exact same areas that got hit on Monday with maybe this being expanded a further bit west and north as well.

[moneypitmike]

Well 150 miles would be pretty massive, but I said "shocked" not expected. Models work buy incorporating previous run's data so I'm not sure how valuable the 18z run will be.

I'm not sure why they would run an 18z cycle. Outside of intellectual curiosity and perhaps a learning opportunity, you'd need to dismiss its depictions. Of course, maybe there are some areas of the country that are immune from the intiialization defects so it would be worthwhile.

[CT Rain]

I'm not sure why they would run an 18z cycle. Outside of intellectual curiosity and perhaps a learning opportunity, you'd need to dismiss its depictions. Of course, maybe there are some areas of the country that are immune from the intiialization defects so it would be worthwhile.

Well you don't have to dismiss it. I'd be more leary of it but I won't dismiss it.

[weatherwiz]

From Southland's wx blog. Discussion can be found here:

http://adiabat.wordpress.com/2010/12/24/boxing-day-storm-tko/