December 18-20 Potential Talking Points

[SteveB]

Mike, we won't know how the downstream features react to the historic blocking until it retrogrades into Central Canada. We'll probably see a wide range of wild solutions until this thing gets closer. As several have mentioned, to get a SECS/MECS we'll have to thread the needle with this system. Last year worked out, we'll know in a few days how we'll fare with this system.

[Edge Weather]

Yes, just saw this. It was an interesting discussion.

HPC continues the threat, in moderation:

PRELIMINARY EXTENDED FORECAST DISCUSSION

NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD

859 AM EST TUE DEC 14 2010

VALID 12Z SAT DEC 18 2010 - 12Z TUE DEC 21 2010

IN THE UPDATED PRELIM...NO MAJOR CHANGES WERE MADE TO THE SEA

LEVEL GRAPHICS. HOWEVER...FOR THE 500MB GRAPHICS...WE BLENDED IN

50% OF THE NEW ECENS ENSEMBLE MEAN WITH HPC PRELIM CONTINUITY.

REASON: WITH SUCH AN ANOMALOUS BLOCKING HIGH WORKING WESTWARD

ACROSS NRN CANADA...WE PREFER WEIGHTING THE DEEPER/COLDER PATTERN

OF THE ECENS MEAN AT LEAST AS MUCH AS THE GEFS MEAN BY THE

WEEKEND. HOWEVER...AS A DEEP LONGWAVE TROF ALONG THE E COAST GETS

RE-INVIGORATED....THE DETERMINISTIC GFS OVERTAKES THE ECMWF/ECENS

MEAN SUN AND BECOMES ONE OF THE STRONGER SOLUTIONS WITH THE

DEEPENING LOW OFF THE VA CAPES. THIS SOLUTION IS NOT OUT OF THE

QUESTION GIVEN THE DEPTH OF THE MEAN LONGWAVE TROF NEAR THE

ATLANTIC COAST. THE EARLY PRELIM DISCUSSION FOLLOWS BELOW.

[A-L-E-X]

Good to here theyre not still dismissing it.

Wes says the possibility for a big snowstorm from DC TO NYC is about 25% and Don also mentioned its reasonable to assume the big cities will get a few inches.

I've always taken "few" to mean less than 6 but more than 2, but beggars cant be choosers lol.

[Stormlover74]

I think few is no more than 3". 4"+ is fairly significant

Good to here theyre not still dismissing it.

Wes says the possibility for a big snowstorm from DC TO NYC is about 25% and Don also mentioned its reasonable to assume the big cities will get a few inches.

I've always taken "few" to mean less than 6 but more than 2, but beggars cant be choosers lol.

[Guest Patrick]

Awhile back, Roger Smith made a compelling argument for a MW/GL cutter in the timeframe of the "OTS" storm we are watching for the upcoming weekend. check out the pinned thread in the main weather forum for the details, but with virtually all the mets spotting the potential in the pattern before it showed up on the models, and roger's argument for the cutter idea, one could make the case that a coastal hugger is still well within the realm of possibilities. Of course, it may be time to just accept the likelihood that this storm will either be sheared out or explode to our east, depending on tomorrow's runs.

Talking about potential, if (and it's a big if) we end up with a massive fish storm, one has to wonder what that does to the pattern as we head into January. We aren't in a typical Nina, so I can't say that we will have a typical Nina January. Assuming the blocking holds, we could be in for one of our top ten coldest January months.

Good to here theyre not still dismissing it.

Wes says the possibility for a big snowstorm from DC TO NYC is about 25% and Don also mentioned its reasonable to assume the big cities will get a few inches.

I've always taken "few" to mean less than 6 but more than 2, but beggars cant be choosers lol.

[gkrangers]

I want to comment on the 12z NAM, but feel unqualified to do so because I tend to forget everything about winter storms every summer and then relearn it every winter, and it is still rather early in the season.

[gkrangers]

I want to comment on the 12z NAM, but feel unqualified to do so because I tend to forget everything about winter storms every summer and then relearn it every winter, and it is still rather early in the season.

Tho the NAM is fo sho more amplified with the energy in the southwest.

[A-L-E-X]

I think few is no more than 3". 4"+ is fairly significant

I may have interpreted things differently, but to me 2 is "couple" 3-5 is "few" and 6 or more is "several."

One is just one of course lol.

[A-L-E-X]

Awhile back, Roger Smith made a compelling argument for a MW/GL cutter in the timeframe of the "OTS" storm we are watching for the upcoming weekend.  check out the pinned thread in the main weather forum for the details, but with virtually all the mets spotting the potential in the pattern before it showed up on the models, and roger's argument for the cutter idea, one could make the case that a coastal hugger is still well within the realm of possibilities.  Of course, it may be time to just accept the likelihood that this storm will either be sheared out or explode to our east, depending on tomorrow's runs.

Talking about potential, if (and it's a big if) we end up with a massive fish storm, one has to wonder what that does to the pattern as we head into January.  We aren't in a typical Nina, so I can't say that we will have a typical Nina January.  Assuming the blocking holds, we could be in for one of our top ten coldest January months.

Thats a good point-- if nothing else, this storm might just re energize the 50/50 and the -NAO

[gkrangers]

Tho the NAM is fo sho more amplified with the energy in the southwest.

I think this run is a step in the right direction.

[A-L-E-X]

I think this run is a step in the right direction.

Glad its a 12z run lol.... I would love to see the 12z GFS AND EURO follow the trend.

[Allsnow]

I think this run is a step in the right direction.

looks good to me at 500mb....alot more amplified and postion of the pv

http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/nam/12/images/nam_500_072m.gif

[A-L-E-X]

looks good to me at 500mb....alot more amplified and postion of the pv

http://www.nco.ncep....am_500_072m.gif

Good, I was just going to ask why isnt anyone updating the 12z NAM thread lol.

[NorEaster27]

NAM looks better than 6z, however it really starts to warm us up at the end of the run....

[A-L-E-X]

NAM looks better than 6z, however it really starts to warm us up at the end of the run....

Isnt the NAM really bad after 84 hrs though?  BTW does it warm us up during the storm?

If this storm is a big one, I can actually see it changing the pattern back to mild.

[Guest Patrick]

That huge vortex to our north argues against that kind of warming...

NAM looks better than 6z, however it really starts to warm us up at the end of the run....

[gkrangers]

Comparing the 12z NAM and 6z GFS at 84 and 90.

Much more amplified with the energy over Texas on the NAM. Confluence over the northeast is significantly more relaxed on the NAM. The PV split has the lobe we need to phase in (right?) over northern WI, instead of centered over Lake Superior like the GFS. The NAM is better all around, I think, and if the GFS followed, would likely end up closer to the coast.

[yoda]

NAM looks better than 6z, however it really starts to warm us up at the end of the run....

Dave mentioned that. He said with the position with the vortex that shouldn't be

[Stormlover74]

Well there's no one definition of course but if I hear several inches I think 3 to 6. Couple and few mean the same to me. But genernally speaking thats why I'm a numbers guy. I hate when forecasters are cryptic and say oh we might get a few inches....2, 4, 6? theres a big difference and that tells me they are hedging their bets.

I may have interpreted things differently, but to me 2 is "couple" 3-5 is "few" and 6 or more is "several."

One is just one of course lol.

[Allsnow]

That huge vortex to our north argues against that kind of warming...

Yeah Dt was saying with the PV up north it shouls not be that warm......for 84 hrs out the nam looks real good as what gkranger said.....84 hr nam so take it with a grain of salt

[A-L-E-X]

Well there's no one definition of course but if I hear several inches I think 3 to 6. Couple and few mean the same to me. But genernally speaking thats why I'm a numbers guy. I hate when forecasters are cryptic and say oh we might get a few inches....2, 4, 6? theres a big difference and that tells me they are hedging their bets.

I agree-- "few" "several" etc are very ambiguous terms!  I like significant and major-- because that's a flag for a 6+ event.

[mahk_webstah]

Well there's no one definition of course but if I hear several inches I think 3 to 6. Couple and few mean the same to me. But genernally speaking thats why I'm a numbers guy. I hate when forecasters are cryptic and say oh we might get a few inches....2, 4, 6? theres a big difference and that tells me they are hedging their bets.

I think it could be pretty hard to nail down a qpf forecast to .1 or .2 which translates to 1 or 2 inches of snow. If a forecaster says a few inches of snow I don't think he/she is really hedging. Would you say that if the forecast was for somewhere around 1/4 to 1/2 inch of rain? If a forecaster says a few inches of snow just assume more than 2 and less than 6.

[ARyan]

Looks like the 12z GFS initialized well, but I only glanced at it. Let's see what it has to see.

[blazess556]

Im liking the look of the 12z GFs through 54 hours right now.

[Quakertown needs snow]

first event further north giving PHL, ABE a little tease

[supermeh]

looks less flat out ahead of the storm.

[hazwoper]

Im liking the look of the 12z GFs through 54 hours right now.

Storm #1 seems to be ahead of schedule and gets off the playing field quicker. I would assume this is good news for us?

[gkrangers]

looks less flat out ahead of the storm.

Through 54, the PV is further west. Liking it so far.

[isnice]

Loos pretty similar to 6z at 500mb, except the pv is slightly further north and west

[yoda]

Through 54, the PV is further west. Liking it so far.

What is that closed 500 energy in SK at 84?