XMAS Miracle: Blizzard of 2010 Lead-in Dialogue

[weathafella]

Sorry to be this guy, but would driving to NYC from Boston starting at 10 AM Sunday be a bad idea?

Bad idea to me.

[weatherwiz]

Do you think that the GFS is somewhat showing that subsidence zone with that "V" that Tip talked about? heavy snow for W MA, Heavy snow for E MA, Screwed in between?

Well I certainly think anything is possible and when dealing with a storm as intense as this is modeled all factors need to be thrown on the table here, sometimes when you see something that is looking as great as this is you tend to overlook negative factors...just b/c the model QPF maps show 1-2'' QPF everywhere doesn't mean that is actually going to happen...this is where bufkit comes in handy.

If any locations see a more northerly component to the low level winds, especially in valley areas that is most certainly going to draw in some drier air now I didn't check to see exactly how dewpoints looked to our north but a quick glance at the dewpoint map from UCAR (for the NAM) looked like they were in the single digits trying to read the contours. That is some pretty dry air and if something like this occurred the question would be how long does it take the air to saturate?

If some places see a NE wind direction, mainly areas they lay to the SW of the hills then we'd have some places starting to get into some serious downslopping problems, so this is another factor to weight in as well but I'd think again this would be confined to the CT River Valley...right now I don't think this will be that large of an issue.

Not saying any of this is going to happen but it's certainly important to keep this into consideration and carefully watch wind trajectories and RH numbers at ALL levels of the atmosphere, not just sfc or the H7 fields.

[dryslot]

NW of the OP I think, pretty heavy snow into ski country

You picked a great time to head to Sunday River, Enjoy your vacation........

[moneypitmike]

New from NCEP:...just have to watch the NE speed on this thing everything else looks great.

THE 12Z GFS HAS A SUBTLE BUT SIGNIFICANT CHANGE FROM THE PREVIOUS

2 RUNS WITH THE SURFACE LOW BEING FARTHER NORTHEAST THAN PREVIOUS

RUNS. BY SUNDAY/18Z WITH A RAPIDLY DEEPENING LOW EAST OF THE

VIRGINIA/MARYLAND COAST...THE 12Z GFS IS ABOUT 40 MILES NORTHEAST

THAN THE PREVIOUS RUN. BY MONDAY/06Z...THE DEEP SURFACE LOW IS

ABOUT 60 MILES NORTH NORTHEAST OF THE 06Z RUN SOUTH OF LONG

ISLAND. AT THE SAME TIME...THE 12Z GFS IS ABOUT 75 MILES WEST OF

THE 12Z NAM POSITION SOUTH OF SOUTHEAST MASSACHUSETTS.

THEREFORE...THE SPREAD BETWEEN THE TWO MODELS HAS DIMINISHED

SOMEWHAT INDICATING MORE OF A CONVERGENCE OF SOLUTIONS THOUGH THE

NAM REMAINS FARTHER EAST.

Great to hear about convergencce--now it's a matter of who's cheering/weeping wrt the prior runs.

[SnowLove]

Bad idea to me.

My parents are so oblivious to everything weather that they literally did not comprehend when I said I wanted to stay home for the blizzard.

They don't realize it's a stupid idea to drive through a snowstorm on Christmas.

[Damage In Tolland]

I'm close to locking in 8-15 here in CT

That's it?

[Clinch Leatherwood]

You picked a great time to head to Sunday River, Enjoy your vacation........

Will wait until tonight to make the decision post 0z. We were going anyway this week...if it's a substantial hit here I'll stay right now it looks like a few inches and then a mix/change/dryslot. I think any increased progression just favors Maine in some ways.

[weatherwiz]

The dryslot does concern me a little, but the models are hinting at big low level frontogenesis..perhaps even extending into midlevels.

This is something to watch closely as well, this would certainly enhance the CF and could lead to some pretty big totals if a CCB can set up over a particular location long enough. Wouldn't even be surprised to see some t'snow reports if something like this were to occur...we do have some positive cape values in place.

[TalcottWx]

What a great day!!! My father proposed to his long time girlfriend and bought her a hell of a ring!!!

[weatherwiz]

That's it?

What would you go with? Right now I'm leaning towards widespread 8-12'' totals with some isolated higher amounts likely.

[Damage In Tolland]

What would you go with? Right now I'm leaning towards widespread 8-12'' totals with some isolated higher amounts likely.

I would lock 10-18 and mention there will be lolli's higher than that due to banding impossible to pinpoint..but 10-18 is certainly reaonsable for all of CT

[weatherwiz]

Wow...nearly 1400 users online

[Organizing Low]

What would you go with? Right now I'm leaning towards widespread 8-12'' totals with some isolated higher amounts likely.

i think thats a cautious and good approach right now.

this is one of those tricky forecasts that youll want to see to see the 00z NAM/GFS/RGEM/SREF trends.... before throwing out any final numbers

[weathafella]

Nice winter snow sky today fully 24 hours out from the big event. Cold....snow's on the way.

[Clinch Leatherwood]

What would you go with? Right now I'm leaning towards widespread 8-12'' totals with some isolated higher amounts likely.

I'd go 6-12 from Kev to Will up from the 5-10 arcing into NH/ME and points SE. 4-8 on the immediate coast south of Marshfield/(south) , from about the north river I'd cut a line SSW towards west wareham on the 4-8 to close to HYA, will be less east of there as depicted now. I'm not sold it doesn't end up more progressive which would pinch it off further ENE and have me a lot less worried about contamination down here. If the low is as far left as it's currently being modeled by the GFS/GFS ENS, it's going to rain in SE MA.

Someone will get more than that in this depiction, probably someone between bob and will and there will be the upslope favored spots and other local totals that could be higher.

I'm probably leaning more towards the GFS track now not sure why, maybe just pessimism and I'm sick of this storm...and I really want it to snow about 1-2' at sunday river

[weatherwiz]

I would lock 10-18 and mention there will be lolli's higher than that due to banding impossible to pinpoint..but 10-18 is certainly reaonsable for all of CT

Well I certainly think there will be some spots that get over 10'' but if you're going with 10-18'' that means the majority of the state would be looking at those totals and when telling that to the public they are going to be thinking more towards the 18'' totals. I don't think the majority of the state gets into the 10-18'' range. In fact I could still see the highest totals and best banding setup more towards the western part of the state as well as higher totals.

For one bufkit at HVN and BDR have 35-45 units of omega located right around 12k-15k in the best snowgrowth region.

Plus NAM QPF has generally around 1'' for CT..with 10:1 ratios and other factors at hand that would probably yield to between 8-12''...hence why I'm leaning towards a widespread 8-12''.

[Typhoon Tip]

Though my opinion counts for nothing ... still, I find the blase language of some of these AFDs to be somewhat spun down and a little miss-guiding as to the potential of this system.

"* HAZARD TYPES...HEAVY SNOW...STRONG WINDS AND LOW VISIBILITY." should equal at least the potential for "Blizzard watches and or warnings may

need to be issued" type special statements - yet we are not seeing much respect given to what is both conceptually indicated, and detailed by the bevvy of guidance types.

Clearly this event could/should produce 3+ hours of 1/4 mile visibility particularly further N along the eastern seaboard where steep pressure gradients and heavy snow fall rates will combine. Someone needs to get some coffee to these boys and girls and crank up the discussion dial a notch!

[DeVries]

That's it?

8-15 is really a bust-proof range for a big storm. If you get 18-20 then you can say you at least called for 15. If you get only 6 then you can say you called for 8.

[Damage In Tolland]

Well I certainly think there will be some spots that get over 10'' but if you're going with 10-18'' that means the majority of the state would be looking at those totals and when telling that to the public they are going to be thinking more towards the 18'' totals. I don't think the majority of the state gets into the 10-18'' range. In fact I could still see the highest totals and best banding setup more towards the western part of the state as well as higher totals.

For one bufkit at HVN and BDR have 35-45 units of omega located right around 12k-15k in the best snowgrowth region.

Plus NAM QPF has generally around 1'' for CT..with 10:1 ratios and other factors at hand that would probably yield to between 8-12''...hence why I'm leaning towards a widespread 8-12''.

Who cares what the NAM has for qpf? Has it ever been correct one way or the other on any event? We've got a slow moving snowbomb enroute

[Damage In Tolland]

Though my opinion counts for nothing ... still, I find the blase language of some of these AFDs to be somewhat spun down and a little miss-guiding as to the potential of this system.

"* HAZARD TYPES...HEAVY SNOW...STRONG WINDS AND LOW VISIBILITY." should equal at least the potential for "Blizzard watches and or warnings may

need to be issued" type special statements - yet we are not seeing much respect given to what is both conceptually indicated, and detailed by the bevvy of guidance types.

Clearly this event could/should produce 3+ hours of 1/4 mile visibility particularly further N along the eastern seaboard where steep pressure gradients and heavy snow fall rates will combine. Someone needs to get some coffee to these boys and girls and crank up the discussion dial a notch!

If only they'd let me write the afternoon disco at BOX today

[weatherwiz]

I'd go 6-12 from Kev to Will up from the 5-10 arcing into NH/ME and points SE. 4-8 on the immediate coast south of Marshfield/(south) , from about the north river I'd cut a line SSW towards west wareham on the 4-8 to close to HYA, will be less east of there as depicted now. I'm not sold it doesn't end up more progressive which would pinch it off further ENE and have me a lot less worried about contamination down here. If the low is as far left as it's currently being modeled by the GFS/GFS ENS, it's going to rain in SE MA.

Someone will get more than that in this depiction, probably someone between bob and will.

That's a good point too about the progressiveness of the system, this will certainly have an influence on snowfall totals as well. Right now I don't discount we end up seeing the models slow this bad boy down a bit as we continue to get closer, models are having a little bit of issue on when this thing closes off, if it closes off further to the south, it definitely slows down near our latitude and we can probably expect a bit more in the way of totals, if it closes off more towards our latitude then that will certainly trim back QPF totals and subsequent snowfall totals.

I like your thoughts, staying more towards the progressive side for now...then if indications point towards slower movement you can always bump up.

[ORH_wxman]

I'm feeling the jackpot is likely in the GAY-ORH-BOX triangle and probably includes BOS....there might be another secondary max out west near God's Country, but I'm hesitant there just slightly because there are models that do not want to wrap this up as much as the GFS does. The way that 5h digs its own grave to the ENE can still make this a bit further E like the NAM/RGEM solutions and have a more compact comma head that shifts its dynamics to E MA ala Dec 9, 2005

It will be an interesting storm to forecast for on a mesoscale basis.

[Damage In Tolland]

That's a good point too about the progressiveness of the system, this will certainly have an influence on snowfall totals as well. Right now I don't discount we end up seeing the models slow this bad boy down a bit as we continue to get closer, models are having a little bit of issue on when this thing closes off, if it closes off further to the south, it definitely slows down near our latitude and we can probably expect a bit more in the way of totals, if it closes off more towards our latitude then that will certainly trim back QPF totals and subsequent snowfall totals.

I like your thoughts, staying more towards the progressive side for now...then if indications point towards slower movement you can always bump up.

Don't be fooled. It's not nearly as progressive as some might lead you to believe

[moneypitmike]

If only they'd let me write the afternoon disco at BOX today

Lol.

I'm out--hoping to hear that the EC is tucked, stalling, and dropping heaps in the hinterlands (and everywhere else, of course!)

Merry Christmas!

[weatherwiz]

Who cares what the NAM has for qpf? Has it ever been correct one way or the other on any event? We've got a slow moving snowbomb enroute

Well I do b/c as of that post that was the only model out with bufkit data to get a good look at QPF. The 12z GFS bufkit is out now so now we'll see what that shows.

Until the models/SREFS indicate strong probabilities of higher QPF totals I'll take the lower side.

[Damage In Tolland]

This sums things up very nicely..Can see where the jackpot will be

[ski MRG]

I'm feeling the jackpot is likely in the GAY-ORH-BOX triangle and probably includes BOS....there might be another secondary max out west near God's Country, but I'm hesitant there just slightly because there are models that do not want to wrap this up as much as the GFS does. The way that 5h digs its own grave to the ENE can still make this a bit further E like the NAM/RGEM solutions and have a more compact comma head that shifts its dynamics to E MA ala Dec 9, 2005

It will be an interesting storm to forecast for on a mesoscale basis.

Might be?lol

[MattdWX]

don't know if anyone has posted this yet but here is the official criteria for a blizzard warning. I could definitely see this is parts of E MA.

Blizzard Warning: Sustained winds or frequent gusts > 35 mph AND considerable falling and/or blowing snow frequently reducing visibility < ¼ for > 3 hours Blizzard conditions need to be the predominant condition over a 3 hour period

Oh and for anyone concerned about P-type issues in the greater boston area I think we don't have to worry too much. Just based on living through these storms my whole life on the north shore, I think immediate boston area and more certainly points just north of town will not have an issue and will likely remain all snow. Also, we usually see some ocean enhancement with a northeast wind, hence why these areas often see the highest totals. Can't wait til the first flakes fly tomorrow afternoon.!!!!!!

[weatherwiz]

Don't be fooled. It's not nearly as progressive as some might lead you to believe

Oh trust me, I agree with you. I was talking to someone on the phone earlier and mentioned I think we will end up seeing this move much slower than models have it but before I base a forecast off the slower movement I want to start seeing it be a bit more consistent in the models...this is why I'm waiting for the GFS/Ukie/Euro before making an official call. I haven't made any map yet so that 8-12'' is preliminary.

[Clinch Leatherwood]

That's a good point thought too about the progressiveness of the system, this will certainly have an influence on snowfall totals as well. Right now I don't discount we end up seeing the models slow this bad boy down a bit as we continue to get closer, models are having a little bit of issue on when this thing closes off, if it closes off further to the south, it definitely slows down near our latitude and we can probably expect a bit more in the way of totals, if it closes off more towards our latitude then that will certainly trim back QPF totals and subsequent snowfall totals.

I like your thoughts, staying more towards the progressive side for now...then if indications point towards slower movement you can always bump up.

6-12 is a very safe bet for the mean 36 hours out on a storm where NCEP still notes some significant issues with participants in the flow. Like you said and like Tip said, it's time to say potential for blizzard conditions and I think it will be a blizzard, just tough to say where.

It's only 24-30 hours away, it can only get so much faster time is running out and the window for major changes barring a total disaster in the models is closing.

50 miles in the storm track may not make a tremendous difference in QPF for eastern areas as much it will on ptype. EC to rule them all, what say she.