wthrmn654 Posted January 3, 2011 Share Posted January 3, 2011 Could it be?!?!.… 2 blizzards 1 week apart? Just a crazy thing to thing bout Link to comment Share on other sites More sharing options...
atownwxwatcher Posted January 3, 2011 Share Posted January 3, 2011 The ECM has been problematic lately. There's that, and, if there were no teleconnector support and the other guidance were doing something else I'd have less problem with it; but seeing as precisely the opposite is true in both cases, I'm willing to think this is no different than that 1.5 days worth of runs it lost the last big event. Remember? I lost count of the "this threat is essentially dead" posts, yet full on blizts struck from VA-ME. Hey John..I am curious to know what you think of the 18 Z NOGAPS actually developing the low as far south as Hatteras but east of Hatteras? By 96 hours this low is relatively in the same spot as the 18 Z GFS is @ 102 hours...What are the chances that something like last nights ECM comes back into play before this event is upon us? In some ways this reminds me to much of the last event that did not really get modeled correctly till under 48 hrs? Thanks in advance! Link to comment Share on other sites More sharing options...
vortex95 Posted January 4, 2011 Share Posted January 4, 2011 Re: the Blizzard of 78 analog. Not really a good analog in some important aspects. 1) There was a much stronger amplification of the 500 mb ridge over the central U.S into Canada as that event unfolded. In fact, so much amplification occurred, you actually got a cut off *high* for over central Canada. Rather rare to see that develop in conjunction with a East Coast storm. We don't have that forecast here. There is a cut off high, but that is already present and much further N due to the high latitude blocking, not due to amplification, and the ridging in central Canada is severely undercut by trofs. 2) Even more of a difference was the at surface. There was a *massive* 1055 mb high centered over western Ontario with an eastern extension of that high over Quebec and the Northeast prior to the event in Feb 1978. Boston had temps close to zero prior to the storm. Not even close to this is forecast to occur, with actually *low* pressure over much of eastern Canada forecast as this event evolves. I would argue that the position and intensity of high pressure around a storm is as much as important as the low itself (high winds, Atlantic inflow, etc). We need to be careful about throwing around historical events/analogs like the Blizzard of 78. Extraordinary events require extraordinary circumstances, and the models do not show some key circumstances leading up to this event as 1978. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted January 4, 2011 Author Share Posted January 4, 2011 Re: the Blizzard of 78 analog. Not really a good analog in some important aspects. 1) There was a much stronger amplification of the 500 mb ridge over the central U.S into Canada as that event unfolded. In fact, so much amplification occurred, you actually got a cut off *high* for over central Canada. Rather rare to see that develop in conjunction with a East Coast storm. We don't have that forecast here. There is a cut off high, but that is already present and much further N due to the high latitude blocking, not due to amplification, and the ridging in central Canada is severely undercut by trofs. 2) Even more of a difference was the at surface. There was a *massive* 1055 mb high centered over western Ontario with an eastern extension of that high over Quebec and the Northeast prior to the event in Feb 1978. Boston had temps close to zero prior to the storm. Not even close to this is forecast to occur, with actually *low* pressure over much of eastern Canada forecast as this event evolves. I would argue that the position and intensity of high pressure around a storm is as much as important as the low itself (high winds, Atlantic inflow, etc). We need to be careful about throwing around historical events/analogs like the Blizzard of 78. Extraordinary events require extraordinary circumstances, and the models do not show some key circumstances leading up to this event as 1978. I agree here with both points. The key is "in the 500mb" - the discussion from HPC was as it pertained to the 500mb stream interaction in particular. Definitely do not have a big 1055high in this scenario - agreed. Also, there is ridge amplitude aloft; as the retrograde takes place up N, we end up with a quasi-Rex couplet with pivoting negative geopotential region nicely correlated underneath. That's also the impetus to this whole thing as discussed.. Anyway, that specific behavior of having SPV subsume southerly stream dynamics in then passing S of LI was the points made - not the entirety of the hemisphere. I have reviewed the balance of deterministic guidance types from 00z and 6z where available and I do not believe anyone from middle MA latitudes and up the coast is out of the woods on this just yet. There is immense complexity in trying to resolve small scale stream dynamics/interactions amid the generalized agreed upon subsuming SPV. Also, the intermediate stream dynamics that really gets involved is still not over the denser sounding grid in western N/A just yet. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted January 4, 2011 Author Share Posted January 4, 2011 in either case, I don't like the fast flow in the deep south and southeast. It is adversely effecting in this case; the phase would be more successful if the S/W (intermediate stream) were not rocketing through there at ludicrous speed. Hmmm Stranger things have happened. Also, said int stream impulse has not relayed off the Pac and into the denser sounding domain over western N/A. This supposedly does not matter any longer with sat and assimilation schemes working together to fill the voids; yet, repeatedly we see system morphology take place down stream some 72 hours after that relay takes place - something has to atone for the differences. We'll see... But point being, if that comes in stronger it may take on more meridional component down stream; a subsuming SPV would take advantage of that. Fast flow just means you got less room to play with so the timing gets more critical. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted January 4, 2011 Author Share Posted January 4, 2011 Wow, the 12z NAM's structure in its poorer verification range is something to behold.. The southern/intermediate stream being caught up in the fast flow proves to much to provide phase. However, it does impart enough weakening of the geopotential medium S that when the retrograding block at high latitudes presses W and triggers the SPV to move S it is just comes down with so much power that the phase is less necessary on this run. Seemed that the last several cycles were heading that way actually via extrapolation, actuallly. It is interesting to see that solution start to emerge - thus. On this run we have light to moderate QPF busting out in snows from DCA-BOS, everywhere, and the next panel if could be seen would DEFINITELY register bombogenesis with that extremeness aloft approaching the Del Marva. Unfortunately we have to nod to NAM's typical poorer latter ranges and wait that out... Link to comment Share on other sites More sharing options...
wthrmn654 Posted January 4, 2011 Share Posted January 4, 2011 So being that ive been sick good part of the week and haven't had the energy to look at anything, based on models at the moment and all, what places have a chance to see snow? Gotta give boss the heads up, state of ny tends to wait till past min to prepare, and have lots of plowing to do lol. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted January 4, 2011 Author Share Posted January 4, 2011 So being that ive been sick good part of the week and haven't had the energy to look at anything, based on models at the moment and all, what places have a chance to see snow? Gotta give boss the heads up, state of ny tends to wait till past min to prepare, and have lots of plowing to do lol. Tough call! As a preliminary guess I woud suggest that the coastal plain along the I-95 corridor N of DCA is the highest probability for median or above median impact relative to local climo on coastal systems. That does not take inerior NYS out of the question altogether, ...just where the probability appears aligned at the moment. I am correcting in mind's eye toward a position closer to the coast based on seasonal trends and Meteorology on such systems combined. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted January 4, 2011 Author Share Posted January 4, 2011 Okay, it is clear what is going on here and the 12z Euro really wonderfully depicts this... It really comes down to the topic of the OP: the flow is too fast in the deep south and southeast and is rearing its ugly factor here. The southerly impulse(s) can't slow down - they get bottle rocketed through the area and this timing screws up the phase potential. If they were slower, ...or more amplified, that would allow room to couple up the SPV with the wave frequency to the south. That is exactly what the problem is and has been with this system since the get go. I posted all that factorization issue and the NAM and Euro runs are now out right showing why it is better to have less mlv wind prior to trough arrival. Best hope here I suspect is to go with no phase at all and do like the NAM suggests - SPV only. Unless the relay off the Pacific Ocean really comes in stronger. Probably the former is the best bet for storm enthusiasts. Still appears New England is the highest probability, but I wouldn't pull plug on the DCA-NYC belt just yet... Link to comment Share on other sites More sharing options...
wthrmn654 Posted January 4, 2011 Share Posted January 4, 2011 Tough call! As a preliminary guess I woud suggest that the coastal plain along the I-95 corridor N of DCA is the highest probability for median or above median impact relative to local climo on coastal systems. That does not take inerior NYS out of the question altogether, ...just where the probability appears aligned at the moment. I am correcting in mind's eye toward a position closer to the coast based on seasonal trends and Meteorology on such systems combined. ah thank your.. .finally got onto my computer and all... being im on eastern long island and all that does help ... what a wacky winter Link to comment Share on other sites More sharing options...
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