Typhoon Tip

Very active pattern the next two weeks... Suspect we may repeat these colorful headline days a few times through the 20th. Scott's more right than re the 15-17th. Current/available indicators have then better as probabilistic for winter enthusiasm. These events in the foreground are in successive order encountering steadily more exertion - apparently - from building/west limb -NAO expression in the flow. The 10th is locked. It's a primarily a wind and flood headliner SW of CT. Much NE of NYC-PVD-BOS line, I have doubts about wind realization with new snow pack and boundary layer drag both impeding mixing. But it gets mild and melts and we rain, nonetheless. Brevity may keep the flood concern to just smaller tributaries and any ice clog back ups. The 13/14th is still trying to lean more coastal commitment, while the ballast of the primary maintains and runs up through Ontario. But that hesitation on the lead side will probably allow for a start up snow/mix over to ice for a time - at this range we can't be certain over how long that would impact/amt, but it's not a "snow/mix storm" either without more changes. But out around 15th+ with unknown ending ... the +d(PNA) has been well underway - I outlined much of that teleconnector business yesterday/above. Although it is the so-called clown range, the emergence of Euro and/or GGEM ( different structures...) are non-zero wintry potentials; they are better seated than mere noise typically found at this range, due to these super synoptic indicators weighting the dice there some.

Winterwolf loves this word so I'll use it again here just for him. The canonical teleconnector correlations, when balancing all projects, is very closely matched to that date range you got there - from what I have been observing as of late. There is a new +d(PNA) ( actually started emerging 4 days ago and is above 0SD as of today) running out through the 20th. That does not appear to be mere noise. There is limited spread in native sources, and they all have the positive delta. Meanwhile, the EPO is tanking rather abuptly negative during this week. We are thus relaying a -EPO into a +d(PNA). That is a cold loader pattern into middle latitude continent. The scale/amount of +d(PNA) is on the order of -1.5 SD to +.5 ...so ~ 2 SD total correction - which is a subtantive amount over an index domain that is very large. It can be dispersed unevenly, granted, but I am noticing a tendency in the spatial ens means, to raise heights over the open Pac Basinc between Hawaii and California. This is typically the type a signal that would lead me to start an extended lead thread for storm threat over eastern America - I'm holding back in deference to seasonal trends. 13th is a bit early for this discussion, but that one is actually in contention for other forcing - in my mind - due to the uncertainties with the western limb variant of the -NAO expression. We are < D7 but ... mm there's still tendencies to smear that E in some of these operational runs. so we'll see on that. It's possible to run a Lakes Cutter and have the low unravel over western Quebec given the -d(NAO) is still in formulation and the exertion isn't matured. Kind of race there - not sure that can be confidently refuted so it's easier to assume a GEFs/EPS blend there.

You mean like the one we just had these last 3.87 years

For those interested ... the 12z Euro does pass a burst of WAA snow through the area re the 10th system. N of the CT/RI border with Mass...but you know what? The entire frontal tapestry of that thing is moving so fast, by the time the region goes over to heavy rain it's over with in a matter of 2 hours. You may actually add some snow, NW of along/N of HFD-BOS... before matting down. But point being, it's moving so fast that removal of the entire ground snow appears less likely.

1/4 mi vis in this band at the moment.

The transformation from this early a.m. to the mid day has been a joy to observe. When I awoke around dawn, there was a subtle but still coherent impression of blue through the veil of flurries and misty sky. But now it's thick. Dimmed daylight and gelid out there. Reminds me of some of those scenes in "The Shining" Passing 9" total - at the rate its coming down now and judging by rad extrapolation etc... probably we're adding inches to this affair. I decided to wait on shoveling out the berm at the base of the driveway. Apparently, our town hired another moron, because this idiot's gone and plowed from the non-residential side, toward the driveways. I mean ... really? Can't that just be sort of automatically noticeable? Now we all have 3 ft road urine snow solidifying into a wall that separates our cars from the road. And undoubtedly... they'll soon re enforce their stupidity with another pass.

Daylight dimming in the last hour. Sky darkened as this moderate steady stuff kicked in. 27 F Vis about .75 mi 9"

Yeah, I just noticed the ICON joining the GGEM there with that forced secondary. But right - ICON. Unless they've upgraded that model, I gave it a try two seasons ago and decided there was no value add

Anyway... beyond snow/winter agenda ... those two events would likely lead to some flooding concerns. If folks want/need/look for headlines in general, that's certainly on the table too. As is at this time in the GFS.

Two aspects about that which are under-the-radar strange. I mean ... if you didn't know any better - But, the storm on the 10th and the storm on the 13th, shouldn't track along the same path in canonical synoptic meteorology. The typical framework/climatology is that each storm tracks east of the predecessor. It's not impossible, but just more typically speaking. The other aspect is interesting... The storm on the 13th can't go anywhere. So it it bombs toward S Ontario and then smears east. That's the exertion of the -NAO ... Which by the way ( you know all this - ) the -NAO ( west limb variant) storm track is actually S of Ontario, OV to MA. Because of these two facets, the entire frame up from the guidance is anomalous one... Handing anomalies beyond D6 is negotiable anyway, but given those two facets above I'd suggest winter enthusiasts still pay attention to that one.

Nice to see ski country perhaps cashing in on -NAO trends... I'm still waiting for the operational model versions to stop trying to physically over power the entire planet with their beady-eyed obsession to drill for oil through Lake Superior - but we gotta start somewhere. LOL

00z GGEM for example... Otherwise, nada/no-go on coastal commitment from other operational versions - although yesteday's 12z JMA looked suspiciously like it bombed the 13th cyclone as it rips a fast mover from the TV to the GOM - I have zip real-time experience with that product though, and it's coarseness doesn't lend to confidence either. So I guess we have the GGEM/JMA against every more higher performance method imaginable - ha, not a good optic ... But we'll see. The NAO is negative on the 13th ( pretty deeply so in the numerical values), with the actual spatial depictions also showing ample hgt anomalies over the western limb. The PNA has even begun to rise - but still negative. It can be argued in both directions. The short version is that if we average the position climo for a -PNA/-NAO, it's just about collocated where the EPS and GEFs mean are for that for that time range. Very interesting..

It's too early for postmortem on this event but so far ... it appears the idea of tempering the outcome may have been the better expectation. We'll see how things play out during the day. Winchendon MA with 3.5" and 7.5" at this end of Rt 2, and I have contact over in Chelmsford with 8" so along the Rt 2 corridor, as of 9 am 'moderate' sufficed for this. Again, we're saying if this ended now, so we'll see where we stand this evening. So far, this event appears to be driven by the lead S/W, albeit attenuating, still with enough thrust to generate isentropic lift. Really, just timed a sufficiently cold air mass ( interior ) with that which could have happened without that cold - so 'fortunate' in that sense. It would be nice to see this evolve into a more cyclonic generation/cross section with that CCB and so forth, to sort of "validate it" further. But ... mm, not sure it really matters either way. Just airing some thoughts on this as obs are coming across my awareness.

7.5" as of 7 am ... Interesting Obs: ...32/31 at 3:45 am; 24/23 at 4:15 am. We have a lot of tree and wire sag. There were subtle hints of a blueish tint to the dawn overcast while flurries persisted. It was like 'blue sky dimly visible.' Very little wind. Very serene. I snapped this pic. Steadier light snow has resumed nearing 9am

The storm’s an hr old and everyone’s saying it’s underperforming. Haha.

this is starting as an OE band here. Storm entry is still down in southern Orh county

It'll be interesting if A ... the GFS actually succeeds in propagating the MJO around a robust phase 4-6 signal like that. B, the WPO is projected to be in an equally handsome destructive interference with that MJO actually doing that. That would argue that even if the wave propagation somehow squeezed through the elephant's ass cheeks mashing down over the western Pacific ... the transmission of the WPO --> EPO in time ( which is already HUGELY modeled to do so) toward mid month, all be precludes the MJO even dispersing any forcing into to the R-wave distribution. It'll be neat to see which signal wins.

Yeah ... See! it's getting cooler

And while not brutally/historically cold, that's an interestingly sustained negative anomaly going from the NP/GL/NE regions, simultaneously while the GFS figures out how to cut storm west. It just seems like we're staring at modeling amplitude biases doing that, particularly when the western limb -NAO variant keeps re-materializing in the means - should back drill lower heights and a NW flow right where the oper versions keep butting heads with that signal. I'm not sold on that traffic routing with those cyclones...

mm if that arm of polar high pressure arming east over 1030mbs is real those surface features over NE are not going to do what that ... sorry, not happening. 14th

Meh ... wouldn't shock me if that decision is largely demographic. Sunday anyway. Wind driven snow or snow and rain.

The only operational run from 00z that actually looks like a reasonably correlation/fit for their ensemble mean is the GGEM. The operational Euro and GFS are almost completely out of phase with their own ensemble mean. This is can be pointed out via numerical telecon, or illustrated just observing the 500 mb total hemispheric geo-potential anomalies distribution ... right out through 360 hours. What all that means is that either the operational runs are wrong. The ensemble means are wrong. Or, they both are, and that reality will blend them. If it is this latter option, how much or how less? Basically, very low skill. Despite the demonstrative and seemingly beady-eyed persistence to drive Lakes cutters ( oper versions) into a -NAO exertion ( ens means), the actual deterministic value there is questionable.

I just looked at the 12z NAM FOUS grid and those numbers would suggest near blizzard conditions due to falling and blowing snow combined sometime between 10z and 14z over the city of Boston and some of the immediate NW-W-SW subburbs. I'm not sure we can get by without at least some marine contamination right at the shore points - just being conservative about that factor. But sustained 36 mph BL wind implication with 31F with pure snow vertical thermal structure ... Coming down Arlington Heights ... and up E of BED and down toward Newton and possibly down toward Milford ... that region would be very low visibility right around dawn tomorrow with impressive fall rates, with occasional wind gusting. This run has nearing 1.5" liq equiv in the QPF column of the FOUS grid for Logan, and all of it as happening in a sub 0C total vertical sounding. Looking down toward LGA on the grid, with well over an inch and a 6-hrly interval exceed .7" (!), then translating NE... Within the run its self, this is a packaged well-behaved deal that implicates the HFD to Boston corridor. Obviously there is other guidance.

It may enhance the CF

I'm not (personally) sure we are in an El Nino circulation manifold. Just a personal observational take. I don't want to derail the thread at this late our... but will offer in brief: The PDO being out of phase with the warm ENSO, all along, is a specter that's been acknowledged, but the limitations on the El Nino forcing/offset ...all that? mmm, hasn't been accepted nearly enough. It's not the correlation between the El Nino and the PDO ( being out of phase) itself that is the problem, it is the correlated hemispheric pattern with PDO, and that which correlates to the EL Nino ... those are competing. For that, I don't believe the El Nino can mathematically be construed as really coupling/forcing much outside subtropics. This is not a very good El Nino footprint hemisphere, and the "super synoptic" behavior ...It gets into a different discussion that ranges between speed of the flow contamination f'ing up the standard telecon correlators... and possible attribution shit, as well as a healthy dose of people not wanting to accept things. Back to storm: I agree with the climo track. Not just that... a lot of metrics in this are really more ideal than not. Mid level wind max traveling 1.5 degs lat/lon S of L.I. tends to pummel the Pike when dealing with the cryo -soundings. Which we have. It's just a matter of the run to run idiosyncratic mechanical headaches, trying to not actually snow for whatever reason. Then reversing the next run(s) ...rinse repeat. Some of that - I believe - is related to the narrowing and "needle thread" nature of this system. I spoke at length about this days ago, that a deterministic headache for this in that it is at the far eastern end of the R-wave signal - that's like the loose end of a hose (metaphor)... Features conveyed through those regions will " flop around" a bit more than where mid way across the R-wave function where it is more predictively (between the ridge/trough couplet) anchored...etc...etc.. This has been behaving like that. These different metrics are scattering around from run to run. When they collocate better in space in time, we get the solid playout... When the scatter, we get a 06z Euro type distraction. After that long blather ...( ha) this will require some NOW-CASTing... Particularly around 12z tomorrow, if there's going to be a CCB genesis we'll probably see the zygote observations beginning to emerge.