Typhoon Tip

That is an insanely ideal exit jet structure up over SNE nose then evac ... that's going to explode the shield NW ... I don't see how that can happen and keep this thing's QPF very tightly wound SE frankly and wouldn't be shocked if this has some smear bust extending farther W and N of the present layout -

I can understand the skepticism .. it is in part a responsible scientific approach, but it is also rather knee-jerk and biasedly overbearing at times, too - Defense mechanism ? I see the 06z solution as just as viable as any other - but that's just me. I don't care if it doesn't succeed at 16.7" of lightning/thunder delivery in 50 mph wind gusts wrapping ripped power lines around fallen timbre ...or if it turns out something much less. I try to see each individual's potential to achieve or under objectively. I don't see any rational reason to auto 86 the more impact scenarios. But I get it that this engagment/social-media is really much more of 'support group' lol

Not to toot horns but this was mentioned yesterday ...yes, and I'm suspectful of meso-B/CSI type banding with plausible thunder given a NAM solution/blended Euro..I rather like the 'EE' rule in this case, because for one ... these sub-synoptic scale tightly wound mid level forcers are handled better by finer meshed meso models - I don't find it a coincidence that the NAM/Euro and the GGEM aren't even returning the GFS calls anymore. Edit, 12z NAM is still just 'giga' motions typical for that model's synoptic scale handling - not likely to deter my thinking ( for now..) I'm also noting the 06z GFS subtly plumbed nuance-more N/stream through Cleveland ( ~ ) longitude, as it is foisting it's S stream vestigial vortex into the NE trajectory ... Which, by the way ... regardless these major player disagreements...pretty much all models indicate a 1.5 deg lat 500 mb wind max trajectory S of L.I. and that fits climatology on frontogenic emergence on the polar side ... Pretty sure someone gets thunder ...and the thing with CSI and banding fall rates - ...well, you know the drill... That height falls was/were noted yesterday and is consistent in the Euro and the blend... instantiating convective instability ( PI ) and then we have the jet mechanics with exception left exit at over top ... The more I think of this, ..looks like a chance at an over-achievement relative to some of these more robust guidance's as it is... I don't see the Euro this incorrect/wrong this close ... and in fact, it could even bump east on that track within an acceptable margin of error for still 72 hours and that would make the diff on accum. of course. I suspect we see thunder whether we are caw paws over to ending cake, or more realized parachutes that dynamically in either case moves toward a cryo finish... Folks ironically - rightfully ... - suggesting this was a highly dynamic reliant event and frankly, these overnight runs have done a lot to bring into focus this system greatest attributes and it is indeed - from where I am sitting - a dynamical text-book/juggernaut paradigm. The 12z should be along now any moment to abase these notions ... we'll see. Strikingly bad mid range performance but as we are turning the page into short turn, I'm starting to hedge in favor of the Euro as being the leader on this guy -

Model Diagnostic Discussion NWS Weather Prediction Center College Park MD 643 PM EDT Sat Aug 15 2020 Valid Aug 15/1200 UTC thru Aug 19/0000 UTC This product has been terminated as of August 15, 2020. For more information, please refer to the following Service Change Notice (SCN): https://www.weather.gov/media/notification/pdf2/scn20-58pmdhmd_term ination.pdf WPC will continue to include forecast evaluations of model guidance in other text discussions, which are described in the SCN. In particular, note that the Extended Forecast Discussion (PMDEPD) has a section specifically providing a guidance and predictability assessment. The PMDEPD is available at the following link: https://www.wpc.ncep.noaa.gov/discussions/hpcdiscussions.php?disc=p mdepd Additionally, advanced graphical tools comparing guidance, including climatological context, are available from the WPC Forecast Tools web page: https://www.wpc.ncep.noaa.gov/#page=tls Gallina good policy ... you stupid assholes telling you ... the n/stream is being inconsistently handled up over the tundra

Nice ... two meso models going opposite directions. Lol

Similarly ... these run variances in the NAM are well within that guidance’s typical error of synoptic scales at intervals beyond 36 hrs. wouldn’t sweat this run.

The N/stream contribution to this is just rounding the arc over NW Terr of Canada where the sampling comes into question. It seems the GFS ‘might’ be missing some physical presentation in the grids - that’s my suspicion. The Euro really isn’t deviating as much as we are accusing. The deviations are being accentuated by the focus subjected need for an idealized solution. We are 84 hrs from max and the track is 150 ... 100 mi ... not horrendous. Just means more rain ..put it this way ... should more phasing prevail ... which major guidance sucked worse ? When it comes to model assessment got to keep our personal biases for what we want to see happen ...out of it. Anyway I thought the Euro would hold and frankly it did - albeit deviating just enough to be disappointing for SNE

Not a bad assessment actually ... To re-iterate...the GFS has a speed bias that is hidden by the fact that the general circulation everywhere has in fact sped up over the last decade. It's sort of 'masking' the GFS' bias inside that making it less notable ...and one such way that manifest is what you are noticing - imho. Because I've noticed that myself - it's the old "right for the wrong reason" ... In other words, I don't know or believe that the GFS is really arriving to these faster shred asunder appeals 'organically' ... It does seem the problems with the Euro began as the seasonal circulations speed up kicked in ... - it's like the environmental arena is changing in favor of one and not the other. interesting - if supposition/anecdotal .. That said, I'm not sure the GFS is right in this case ... just yet. Like to see the N/stream get sampled better as it is N of Alberta/Manatoba over the lower archipelago of the NW Canadian shield as of 18z ... It cold nose over the border at 10 kts added and make a big difference...

heh... right - less familiar with that operationally ..no idea

Curious about that 18z Euro run ?

I wonder why it took so long I mean I'm not complainin' ...it's the NAM deep field .. .but why it took longer to bump that placeholder through the lower OV.. ? interesting -

Haha I know .. it's so funny - ..it's like after all peregrinations and brilliant insights have avered ... gee, it snows more up north - who woulda thunk

Hmm.. play-by-play on the NAM beyond 36 hours ... be that as it may, I think this solution still phases...may later ... but I'm only out to 66

I bet the the 18z Euro holds - or ...we can finally at last petition the gov to discontinue owing tax dollars to that particular org - hahaha

Hey ... I meant that caveat emptor ... 'if the gfs solution pans out ... fo' gettabouit'

I wouldn't worry about titles of threads ... heh but if we must, sarcasm ? "I figured I'd doom for merely posting" being the sarcastic jest -

mmm ... mixed ideas. Statistically, there are diametric signals - like... the QBO is now four months positive and gaining strength - at least in last check in the 30 hPa level, ..or about mid depth along it's vertical tidal journey, ... it was over 10 m/s in the westerly ( positive) phase, and given the previous 3 months, probably continues to rise. That is against the SSW statistics but ... I don't know what the qualifications are honestly? I don't know if that limitation (statistically) like kicks in at 5, 10 ... 15 or 20 m/s... Or, what level..I mean the QBO really terms deeper in the atmosphere before it's momentum washes out and then it starts anew from the other direction - etc..etc... But, 30 is mid depth, and looking at all QBO's ..it's nearing moderate strength so heh - That's a b, we are in a pretty fantastic solar minimum. ... having said that, deliberately just to mock me, God threw this at us: "CME MISSES EARTH: A CME launched into space by a major solar flare on Nov. 29th has missed Earth. This is hardly a surprise. The blast site was located behind the sun's eastern limb; at most, a glancing blow was possible. Auroras watchers can take solice in the fact that direct hits will surely come in the months ahead as Solar Cycle 25 continues to intensify. It's just a matter of time. Aurora alerts: SMS Text..." he's such a dyck - anyway, excluding a Carrington Event swooping down just in time to really give us a cure for the Pandemic ... we are in fact in a solar minimum over the preceding several months of summer,...allowing reduced UVM penetration into the polar domain,... where by theoretically, ozone has increased residence for avoiding being electromagnetically broken down ... ( UV light does that to ozone). Increased ozone is a thermal trap ... such that as planetary waves terminate at high altitudes/latitudes ... ( WAA termination )... the heat is dumped into the PV where the ozone absorbs and viola -...flashes a warm bubble... that then penetrates down due to normal planetary mechanics of the vortex... Interacts with the tropopause...increases the stability .. .PV breaks down, blocking ensues ... -AO So, we have a bad QBO and a good solar ... offsetting - Dice? ...I dunno I'll also point out though...that look there .. "kidney beaning " of the vortex ...wouldn't be related to SSW - it can.. but not in this case. The entire SSW phenomenon --> AO forcing is a huge temporal ..protracted affair. It's like a 20 day gestation. Warm node appears...starts propagating down...it takes 10 days ...then another week to start seeing AO response. There has been no antecedent warm flashing events in the stratospheric over the poles - unless someone has some extra-double top secret data that hides reality -

That's an interesting achievement ... kind of stands in the face of the QBO, huh - Although..you know, with the QBO recently demonstrating the first ever in the 120 year history of it's exposure, failing to succeed it's clock-work timing of oscillatory periods .. it makes me wonder if something is happening in the macro sense of it that is really sort of "disconnecting the circuitry" between it, and the polar regions. ..if perhaps unprecedented/first time. But at the implication level...if that sets up you don't need a split..That's a down right cross polar flow from the deepest N. Hemispheric cryogen factory right into eastern N/A.

Looks like the contention has really been reduced to the amount of phasing between streams. The GFS is being the stubborn limited outlier ... where there is growing consensus from the other guidance. Bit of a guidance battle afoot - I know the Euro has taken it's licks in the last couple years ...I almost sense/think that the speeding up of the hemisphere in the means is presenting specific challenges to that particular model ... It's sort of like the arena is changing on it and it's 4-D corrective algorithm genius is getting out-moded ... But that's obviously intensely speculative - ha! Anyway, the GFS really almost has no phase even though we are but 90 hours from supposed max impact by the zesty Euro/NAM/GGEM blend...which show substantially more. The GFS's unwillingness really materialized the moment all the models gave up on the latter system for the 7th/8th/9th of December in lieu of this one for the 5th/6th ... The previous GFS solution interestingly showed more phasing ..but when this came back into scope, it's just not getting on board. I'm willing throw myself under the bus and wager that the GFS is less correct in this case. Tho all models have their annoying little gem biases ... the GFS has a speed bias ( in a fast hemisphere as it is, which hides its bias ironically ...) and thus, I don't think it is handling the delicate speed handling in the phasing harmonics of the N and S stream wave mechanics. Some pricey words to describe that it's not really the right model to spearhead this storm's project - ha. That said, we'll still be nailing down particulars with timing and track... but for now, I'm inclined to strong coastal/ near by cyclogen that may approach bombogenesis...and I also think going from a relative warm column to a deeply imploding mid tropospheric height core as this thing's thermodynamic processing is passing through... sends some interesting convection signals... Supposing a Euro solution verifies, we probably have this sort of thing to contend with from NE CT to southern Maine, "...Forecasting such convective snow events is made even more difficult by the meso-β scale banding (with halfwidths of approximately 100 km) that is usually observed in these events. Moore & Blakely (1988), Weismuller & Zubrick (1998), Nicosia & Grumm (1999), and Martin (1998a, 1998b) have all presented case studies in which meso-β bands of heavy snowfall fell in regions of otherwise light to moderate snowfall, likely in the presence of either potential instability (PI), conditional symmetric instability (CSI), or weak conditional symmetric stability (CSS). PI is a state of the atmosphere where a lifted layer achieves a statically unstable lapse rate, resulting in upright convection....." C/o https://rmets.onlinelibrary.wiley.com/doi/pdf/10.1017/S1350482703003074 Very important caveat emptor: If the GFS solution is right, ...none of this will happen

Looks like we three threads now... The December monthly discussion focus - The storm specific thread now 84 or so hours - The Best Buy nerd squad thread where one would rather have a spalling bullet molecularly transported into their brain box -

Here ... 'nother words, read this paragraph: "Forecasting such convective snow events is made even more difficult by the meso-β scale banding (with halfwidths of approximately 100 km) that is usually observed in these events. Moore & Blakely (1988), Weismuller & Zubrick (1998), Nicosia & Grumm (1999), and Martin (1998a, 1998b) have all presented case studies in which meso-β bands of heavy snowfall fell in regions of otherwise light to moderate snowfall, likely in the presence of either potential instability (PI), conditional symmetric instability (CSI), or weak conditional symmetric stability (CSS). PI is a state of the atmosphere where a lifted layer achieves a statically unstable lapse rate, resulting in upright convection." it = the Euro run at 12z from about Willamantic CT to Bangor ME

In deference to the Euro run..... Yeeeeeah ... unfortunately, at risk of bundamentalism ... I don't think that can happen at 2-5" of snow relative to what that particular guidance shows... nope. That needs a correction. Negative tilted --> closure, and then shedding 12+ DAM of core heights as it is bundling up and passing over head pretty much can't happen without thundersnow and rates consistent with... If we get into a CSI/convective rangle ... no "snow map" is gonna narrow that down. You'll end up with 4 to 6" per hour rates somewhere that doesn't deserve like Kevin... Even at 9::1 blue snow, you'll choke the vis down to 1/16th of mile with blue flashes flaring through window panes followed by rattling rafters. Sorry for the rhetoric but that is excessive instability signal there.

You know ...there may be a fascinating story-line evolving with this particular "winter" storm - ... Usually, it comes down to storm track as to whether x or a location gets it, and what ... This? We may nail down the track guidance surprisingly well ...and still have to now-cast our way through ( specifically ...) whether dynamics succeed in flipping over to snow, and that's a damn peculiar and uneasy metric to have to rely on the model accuracy for I'll tell ya - ... I mean, we've seen supposed paltry ( modeled ) systems go over the parachutes at 38... We've seen CCB heads "unjustly" stay cat paws while level 3 green rad slabs away midst 35 F I can't recall ..I think it was five years ago 6 years ago Feb 2014 ...but there was a coastal with the Euro had a nice CCB head at 33 F and it stayed rain - in fact I think it busted the model by doing so... Anyway, this may end up a unique metrical challenge for NWS Box if they have to decide on Adv/warn or nill based more solely on thermodynamic accuracy

blue bomb incarnate ....

so now the Euro's a fantastic model all 's and everything -