Typhoon Tip

Not for not .... The Euro seemed to perform best with this weird cold event.

GGEM model keeps putting all the emphasis on the lead side of the trough/S/W that's running up through the 10th... The Euro does much less of that. It clamps that response down to almost negligible and waits for the after S/W to rotate around ...and yadda yadda yadda. The GFS has both... It triggers a lead... but then minors it out as a smear, then detonates a new coastal with not enough cold. yeah, solutions are all over the place.

Mm...looks unremarkably different than prior runs to me. 'Sides...I need the ensembles to stop sending the system up the St L seaway for starters... The operational runs... okay - but we're at a range whence the oper version may as well just be another ensemble member. The EPS mean did have more a system like it's deterministic version ( 00Z) but, it has a structure that suggests the deterministic version is an intense outlier. Euro has history for amp bias at this range, too. I would say the 00z deterministic Euro is lofty hoped outlier until we see some semblance of agreement coming from the varied other sources.

What? that's weird... NCEP has a paper out there about the CFS that says that it has modest cool bias - owing to the fact that it's parameterized with 1988 climate metrics. I posted this along with a link to the paper a couple weeks ago, folks. The opposite of a warm bias, is what they've formally published. It needs an upgrade - in other words ... - to account for climate change. whatever. Either way... it's got like repeating hits out there right through the end of the month. It's also got a dominating pattern construct over the hemisphere that is really quite - ironically - diametrically opposing that of the La Nina late winter --> spring climate. That's odd for a "Climate" Forecast System... but who knows why-for

The ICON solution is f'ing awesome... (12z )... I really have come to the conclusion this model does not belong in the pantheon of the majors, based on my own observation of it performance - it's just outclassed. But hey,...I gave the f'er a real chance and it blew it too often. That said, the run in a vacuum has about 3" of sleet and ice for interior SNE, in a waling Nor'easter that would undoubtedly then transition as an exit 6" of snow on top. I'm just sick enough to think that might be a funner experience than having that snow...

Ha! I was just looking at that - I applaud your bravery in daring mention that match in this perfect saturation vapeor pressure ratio of gasoline and air mixture ... You got some goodly sized plums there. Lol

I was giving this some thought, that 'specific' concern regarding combination - Like I said, the "the advection aspects" - I was including the sustaining wind/gusting as windchill, in that heading and at a regional scale. But as far as at this location/Ayer, there was a nor-easter in 2015 that had 12 hours of winds gusting to 50 mph in occasional milkshake white outs, at 1 F above zero! It went to -5 before coming back after midnight. That's unfortunately countable if doing a straight up comparison. Also, there was other times in that 2015 stretch where we sustained back side advection with single digit cold... So not as deep in wind chill, no, but close...and sustained for many hours. 2016 also had temperatures similar to this in that event, though I don't specifically recall the wind chill numbers in that. So, like I said...I give this one an edge at a regional scope. But it's debatable at this local area of N. Middl. Co whether this is the alpha romeo at in the VIP cold class. I guess in the end it's really a nerds rage, because at civility concerns any of those scenarios of lore would just about be sensibly indistinguishable

Looks like we bottomed out at -13 here in Ayer. Most home sites accessible via the web are -12 to -14... We've been at least that cold several times over the 11 years ( too long!) I've lived at this location. I'm sure overall this event was historic for x-y-z reasons. There's no intent to dispute. I'm sure someone's frozen to death, or someone's got a 60K burst pipe this or that or the other validating horror... But in so far as what was empirically observed here in N Middlesex Co/W of 495, this was not an "all-time" ordeal. It was on par with handful of bottom miserable cold scenarios. It was certainly an out of the blue and strange one!! The cold on Mt Washington, Boston... and just the advection aspect, too, these were all measured and clad. Together with the overall obviously should give this a distinctive edge at a broader consideration.

Ensemble mean is instrumental at this range - At least from my position - the discussion is just wrt what the model runs illustrate, on the 00z cycle. I realize people are starved to the brink of sanity for some semblance of a non CC afflicted season ( LOL... j/k), and thus float a thumb over the apoplexy a-bomb button. But there's no aver here as to a D8.5 - 10 ranged scenario. Personally...mm the pattern we are seeing emerge in the ~ 9th -15th window is uncharted territory. I.e., hasn't happened this year. Which is to say, a relaxed flow +PNAP structure occurring while there is lingering/ample hydrostatic gradient, N-S, through mid latitude continent. It may be difficult to do, but I would encourage folks look at events within the period in question more uniquely, as the erstwhile persistence may take a hiatus for that time span. ...probably not...but I thought I'd advance the impertinent implication of actual lucid objectivity, anyway haha

Re the 00z guidance... The GFS picked up where it left off at 18z ( and perhaps priors-), propagating a L/W across the mid latitude continent ...unable to give any one of the finite S/Ws contained a mechanical proxy. This finite scale destructive interference still manages to activate the barocinic leaf and QPF between the TV and NE region, but keeps the totality unable to fully connect with the best perceived S/W timing into the backside of the L/W ... Such that the lead activated axis actually still sets up a substantial ice storm signal along Rt 2 to roughly RUT-CON in NH with snow of unknown amt above, cool rains south... It's basically a busted ravioli system in the GFS... It ends it all as a period of snow collapsing SE as the rest of the trough then limps through consequently too weak with overall cyclone proficiency. The Euro ...possibly owing to the 4-d smoothing tech it applies/scrubs the charts with out in time ... caries a L/W across that has less of that intra-scaled tussle.. Namely, it damps out the lead impulse(s) more, such that the main one coming into the backside can take proxy and is thus able to catch up and physically connect with the b-c axis more proficiency...and the coastal becomes an easy mark at that point - in part because there is just an exquisitely perfectly timed polar-arctic high moving through Quebec as the gunk approaches the M/A coast, underneath. Boom... - in an aside note, the fact that it's not an overly conked out hyper -bombed as a result, but just has a sensible/seasonable Nor'easter in the cinema, gives this particular model run much more Oscar buzz for me...

Yeah..not sure what they are looking at ...or think they are looking at - late to party this morning but that 00z Euro run was a classic Nor'easter. Snow NYC-BOS corridor, even penetration E CT RI and parts of SE Mass, with typical flip to rain the Cape... Just talking about this one run, mind you. The 204 position and synoptic metrics are almost perfect in this rendition here: That's probably 8-12" for almost everyone in the forum queue, verbatim.

Nasty ice storm central NE

3 for the moment ...

Anyone want a lesson in destructive interference ... look at the 18z GFS

Gummies?

That's a good question actually... man, I wish we had all this telecon wizardry and cinema back on circa February 15, 1956... What would that've looked like. It's also like that for 1978... 1888 - man that'd been a neat D10, huh

Hahaha... let's not get carried away.. but I like the vibe

It's fascinating really... All these longer term correlations going the other way, while the operational and ( we'll see if it sticks -) now the ens constructing the north Pacific with the AB mode/ridge up there. I mean I think that's the crucial piece...that construction is setting the wave scaling down stream into a favorable continent/+PNAP... It even transitively sets the NAO upon a trajectory that might emerge more negative - given time. We'll see on that... But if you're a winter enthusiasts, this is what you wanted to see all along - these hints of favorable pointing 'correction vectors'. Next thing to look for is continuity.

It's similar to the 00z GGEM with a strong ejection of the lead disturbance ...10th... Not sure I'm buying that. The 00z to 12z position of that feature in the D6-7 range was quite the east adjustment, indicative of continuity issues with that aspect. The following more important trough identity upstream is actually more consistently placed in longitude, and yes ...it times with the GFS - but the lead aspect is suspect to me.

Exactly ... question is, when? Even residually the Nina "memory" should promote a warm-ish spring. But let's assume the 'booster' idea works in favor... maybe we can get these last several cycles of the deterministic GFS to win through the 20th or so, and get enough snow to ruin the futility while keep us safely inside of aggravatingly at a loss hahahaha. J/k... but in all honesty, I wasn't think that this cooler pattern we are in would protract through mid month, but the GEFs at 00z hinted in favor of the oper. a bit more.

This turn around is really fascinating for "weather enthusiasts" Not so much - maybe - for "winter enthusiasts"

That's not true ? It's not black or white ... - and it was not "exotically" well coupled, either. What do you think driving the Pac jet up San Francisco's bum for 3 straight weeks was all about. LOL

Sort of like that ... but in this case, the difference are even closer spaced within the L/W. Both solutions have the GGEM's "10th" -it's really more of an emphasis thing. The GFS is weak with the lead, the GGEM is intense. The difference morphs what can/would happen toward the EC out in time.

yeah...The usual ensemble reliance is probably the course of lesser regret for now. Although, I think the GGEM's total synoptic evolution is nod toward a GFS type solution - it could simply be in flux modulating toward the more +PNAP nested look of the GFS. Just needs some another cycle or two. If the ens means of both start converging - and the Euro joins, we have specified event within the 10-15th arena to focus.

GGEM and GFS are really completely different evolutions. The fact that the GGEM is smeared between the 10/11th ...and the GFS is 11/12th might be clue there. But looking closer at the total integral of the whole synoptic space, the GGEM keys in on a lead S/W ejected out of the L/W ... really by the 9th, just 6 days from now. It's already passing STL. It is, however, a significant correction SE at least with the track aspect alone comparing the 00z rendition. If future runs were to dump the lead S/W emphases/idea, it probably defaults quickly into a GFS type latter aspect... The GFS has that lead feature weak and ejected even sooner... flat and heading due east into the Atlantic graveyard, instead putting all emphasis on the aft region of said L/W, which ejects more full bodily a day or so later and ends up being a weirdly non-committal coastal low. That seems like it tried to "bomb" but failed, and ends up with that open core look like that. I think the progressive bias that is native to the GFS, particularly out in time...may be tripping it up in terms of timing critical intra-trough mechanics. It like facilitates its own internal destructive interference between jet maxims.