CoastalWx Posted October 21, 2012 Share Posted October 21, 2012 Indeed... the GOA low is a direct consequence of the ridge building event taking place with the remnants of Prapiroon interacting with a mid-latitude shortwave. Here is a nice annotation of the forthcoming interaction below. These type TC/ET interactions can be difficult for the modeling to handle, but the real uncertainty lies when the GOA low cutoffs below a formidable Rex block over Alaska. These little shortwave pieces that eject out of this large upper level disturbance are pretty much nearly impossible to forecast beyond day 5, especially in a region that has poor upper air observation sampling. I should mention that this is a dynamic tropopause (DT) map, plotting pressure on the DT surface, winds, and cyclonic relative vorticity layer mean average from 925-850 hPa. Nice animation, thanks for taking the time to put those together...allows for the enthusiasts to see what we mean. Link to comment Share on other sites More sharing options...
Damage In Tolland Posted October 21, 2012 Share Posted October 21, 2012 @danburyweather: FWIW: 12z EURO implies a strong (at least) Category 1 hurricane hitting the NYC metro area, sfc wind 86mph on LI and SW CT #wxedge more soon Link to comment Share on other sites More sharing options...
phil882 Posted October 21, 2012 Share Posted October 21, 2012 While the 18z GFS suggests that 99L goes out to sea, notice that it has nowhere to go as the blocking cutoff low prevents much in the way of northward movement. The solution in a way is more akin to Grace and the Halloween Storm (1991) where Grace gets ripped apart as a new stronger extratropical cyclone develops off the Northeast shoreline. Link to comment Share on other sites More sharing options...
andyhb Posted October 21, 2012 Share Posted October 21, 2012 While the 18z GFS suggests that 99L goes out to sea, notice that it has nowhere to go as the blocking cutoff low prevents much in the way of northward movement. The solution in a way is more akin to Grace and the Halloween Storm (1991) where Grace gets ripped apart as a new stronger extratropical cyclone develops off the Northeast shoreline. Yeah, I noticed a few of the earlier runs of various models were akin to the 1991 storm (which is the "Perfect Storm", for those who are unfamiliar with it/the book/the movie). Link to comment Share on other sites More sharing options...
CT Rain Posted October 21, 2012 Author Share Posted October 21, 2012 18z GFS is interesting... sneaks Sandy just enough to the east to pass underneath the ridge. Still we get a nor'easter out of it but not from Sandy. Link to comment Share on other sites More sharing options...
billgwx Posted October 21, 2012 Share Posted October 21, 2012 FWIW, the 18Z GFS ensemble mean of 500 mb heights at T+120hr showed that the 50-50 low is not displaced as far SW as in the operational 18Z run, but is still a little farther SW than in the 12Z ensemble mean, so maybe the ridging won't break down as much as the operational 18Z suggsts? Big ensemble member spread up in ern Canada and the nrn Atlantic with that low, also in the northern Pacific with typhoon remants as someone else mentioned? Low predictability and high potential impact still on the table IMO...we'll just have to wait and see. Link to comment Share on other sites More sharing options...
free_man Posted October 22, 2012 Share Posted October 22, 2012 Maybe a Ginny '63 -type solution? Link to comment Share on other sites More sharing options...
NorEaster27 Posted October 22, 2012 Share Posted October 22, 2012 Maybe a Ginny '63 -type solution? probably a weaker this: http://en.wikipedia.org/wiki/Hurricane_Noel Link to comment Share on other sites More sharing options...
okie333 Posted October 22, 2012 Share Posted October 22, 2012 7-8 days out you forecast becomes much more heavily weighted toward climo, a climo track for anythnig that forms in the caribbean is out to sea. Its actually an easy forecast at this stage. And exactly how is a -2SD NAO climo? Link to comment Share on other sites More sharing options...
Brian5671 Posted October 22, 2012 Share Posted October 22, 2012 If I'm not mistaken the GFS has this for Halloween and the Euro was faster with an impact on Mon 10/29? Link to comment Share on other sites More sharing options...
CoastalWx Posted October 22, 2012 Share Posted October 22, 2012 People need to remember there are many different things that need to occur for this to be Kevin's dream storm. Treat models as comedy relief for a few more days. It's not worth getting pumped up right now. Link to comment Share on other sites More sharing options...
SquatchinNY Posted October 22, 2012 Share Posted October 22, 2012 People need to remember there are many different things that need to occur for this to be Kevin's dream storm. Treat models as comedy relief for a few more days. It's not worth getting pumped up right now. Agreed. The models will flip/flop. Link to comment Share on other sites More sharing options...
ORH_wxman Posted October 22, 2012 Share Posted October 22, 2012 People need to remember there are many different things that need to occur for this to be Kevin's dream storm. Treat models as comedy relief for a few more days. It's not worth getting pumped up right now. Yeah I mean I'm not sure where the excessive weenieism is coming from. If this were a winter storm threat at 8 days out, people would get weenietagged back in the day for going nuts over it. Even last year, we didn't take the halloween HECS seriously until about 48-60 hours out. We kind of mocked it at D5. I guess since we haven't had an interesting storm since then, people get antsy. Link to comment Share on other sites More sharing options...
dryslot Posted October 22, 2012 Share Posted October 22, 2012 Yeah I mean I'm not sure where the excessive weenieism is coming from. If this were a winter storm threat at 8 days out, people would get weenietagged back in the day for going nuts over it. Even last year, we didn't take the halloween HECS seriously until about 48-60 hours out. We kind of mocked it at D5. I guess since we haven't had an interesting storm since then, people get antsy. We may be heading to an early start on this this season, That and troll post from outside the region Link to comment Share on other sites More sharing options...
ORH_wxman Posted October 22, 2012 Share Posted October 22, 2012 We may be heading to an early start on this this season, That and troll post from outside the region Well troll posts from outside the region are gonna get slammed down quickly when we get into winter mode...or even if this storm become a serious threat. Nobody can say we aren't a bit lenient when its slow...but I think most people are good at contributing seriously when its time to. Link to comment Share on other sites More sharing options...
CT Rain Posted October 22, 2012 Author Share Posted October 22, 2012 It's certainly going to be interesting to see how it evolves. At the least, there probably will be some moisture pulled in here indirectly at some point...even the more mundane 18z GFS shows that. Kevin is leading the weenie train, wearing his WOTY crown as the conductor hat. Yeah if I had to guess I'd say an 18z GFS kind of solution is most likely. I think we'll see some kind of storminess as the trough digs over NEUS. I just posted something on my blog about the model porn lol. Link to comment Share on other sites More sharing options...
SquatchinNY Posted October 22, 2012 Share Posted October 22, 2012 Yeah if I had to guess I'd say an 18z GFS kind of solution is most likely. I think we'll see some kind of storminess as the trough digs over NEUS. I just posted something on my blog about the model porn lol. Nice post. Do you think the storm that does effect us will be a coastal-hugger, a GLC, or what? Link to comment Share on other sites More sharing options...
SN_Lover Posted October 22, 2012 Share Posted October 22, 2012 Wounder why the optimistic mood here has quickly transitioned to the pessimistic mood. The trends are still good for the time being. the runs earlier today were perfect in a synoptic sense. to everyone who is saying it's so far out, needs to understand that when ALL models are saying something will happen then it warrants more attention. Not to say it will happen as the models now suggest, just saying as of right now with the trends, the probability of something happening is rising. Link to comment Share on other sites More sharing options...
CoastalWx Posted October 22, 2012 Share Posted October 22, 2012 Wounder why the optimistic mood here has quickly transitioned to the pessimistic mood. The trends are still good for the time being. the runs earlier today were perfect in a synoptic sense. to everyone who is saying it's so far out, needs to understand that when ALL models are saying something will happen then it warrants more attention. Not to say it will happen as the models now suggest, just saying as of right now with the trends, the probability of something happening is rising. Telling people to keep there thoughts in check about a 1-200yr event progged by models is reasonable imo. That's not pessimism. Link to comment Share on other sites More sharing options...
CT Rain Posted October 22, 2012 Author Share Posted October 22, 2012 Wounder why the optimistic mood here has quickly transitioned to the pessimistic mood. The trends are still good for the time being. the runs earlier today were perfect in a synoptic sense. to everyone who is saying it's so far out, needs to understand that when ALL models are saying something will happen then it warrants more attention. Not to say it will happen as the models now suggest, just saying as of right now with the trends, the probability of something happening is rising. I think all anyone can say is the pattern is pretty anomalous. We're still 2 or 3 days from hyping or getting all amped up about anything. Link to comment Share on other sites More sharing options...
weatherwiz Posted October 22, 2012 Share Posted October 22, 2012 Wounder why the optimistic mood here has quickly transitioned to the pessimistic mood. The trends are still good for the time being. the runs earlier today were perfect in a synoptic sense. to everyone who is saying it's so far out, needs to understand that when ALL models are saying something will happen then it warrants more attention. Not to say it will happen as the models now suggest, just saying as of right now with the trends, the probability of something happening is rising. "Trends" certainly are a good thing, however, when dealing with a solution as extreme as this you need to get perfect phasing of all the key ingredients...models can be as consistent as they want but in the end if one piece of the puzzle is even slightly off you can forget the perfect phase and forget the extreme solution. I don't think anyone's mood should be optimistic right now for a major event. Link to comment Share on other sites More sharing options...
billgwx Posted October 22, 2012 Share Posted October 22, 2012 Final thoughts for tonight... Just remembered a known GFS bias from winter weather forecasting that could be in play...that its forecast polar jet on the poleward side of 50-50 lows tends to be too strong, giving them too much influence and suppressing ridging to their SW. Ridging to the immediate east of the cyclone was also weaker in the 18Z run, allowing a more easterly component to the track right from the start. Both of those will impact potential phasing with the northern stream. Perfect phasing to bring about a direct East Coat impact is still within the realm of possibility, but will really be threading the needle. Link to comment Share on other sites More sharing options...
CoastalWx Posted October 22, 2012 Share Posted October 22, 2012 Final thoughts for tonight... Just remembered a known GFS bias from winter weather forecasting that could be in play...that its forecast polar jet on the poleward side of 50-50 lows tends to be too strong, giving them too much influence and suppressing ridging to their SW. Ridging to the immediate east of the cyclone was also weaker in the 18Z run, allowing a more easterly component to the track right from the start. Both of those will impact potential phasing with the northern stream. Perfect phasing to bring about a direct East Coat impact is still within the realm of possibility, but will really be threading the needle. Likewise with the euro sometimes getting phase happy and wrapping lows too far west. Link to comment Share on other sites More sharing options...
billgwx Posted October 22, 2012 Share Posted October 22, 2012 Likewise with the euro sometimes getting phase happy and wrapping lows too far west. Yep. Even brought Irene too far west last year. Link to comment Share on other sites More sharing options...
Typhoon Tip Posted October 22, 2012 Share Posted October 22, 2012 Indeed... the GOA low is a direct consequence of the ridge building event taking place with the remnants of Prapiroon interacting with a mid-latitude shortwave. Here is a nice annotation of the forthcoming interaction below. These type TC/ET interactions can be difficult for the modeling to handle, but the real uncertainty lies when the GOA low cutoffs below a formidable Rex block over Alaska. These little shortwave pieces that eject out of this large upper level disturbance are pretty much nearly impossible to forecast beyond day 5, especially in a region that has poor upper air observation sampling. I should mention that this is a dynamic tropopause (DT) map, plotting pressure on the DT surface, winds, and cyclonic relative vorticity layer mean average from 925-850 hPa. Great use of annotations - yeah, and I agree. I mentioned this earlier in the the day that the relay from the western Pacific is instrumental in getting the -EPO in play - that EPO ridge then retrogrades S/SW and the PNA rises, pretty dramatically actually, as a direct result. The end result might be an ~ 2.5 SD rise in the index, together with an on-going -NAO puts a strong negative geopotential anomaly signal between the OV and the MA. I also mentioned that without the ingestion of a tropical entity, this signal alone is impressive and coastal cyclogenesis potential is hightened/favored. Whether we happen to see a well timed TC get caught up into the fray is entirely questionable - who knows. Time will tell if this is a real hybrid threat, or just another typical autumnal modeled uber phase. What really impresses me also is what was pointed out earlier in this thread, that there is a 4 (guess) SD 250mb easterly jet S of NF punch WSW, while there is a right exit region of a screaming polar jet in eastern Ontario not too far from NYS - this latter jet configuration has been papered as correlated to New England run ins with TCs. This was around D6 and 7 on the 12z GFS. The introduction of that 250mb jet, which is caused because ridging over the lower Maritimes is pressing against a westerly displaced Azores Low (it's anomalous for -NAO which tends to find that feature farther east in the Atlantic Basin) definitely makes things that much more intriguing. Link to comment Share on other sites More sharing options...
CT Rain Posted October 22, 2012 Author Share Posted October 22, 2012 really? so it's best to say "it's not going to happen"? ok... I'm quite confident a hurricane ~950mb will not be over D.C. next Monday. Link to comment Share on other sites More sharing options...
Junbug Posted October 22, 2012 Share Posted October 22, 2012 im not saying to hype it. nowhere did i say that in my post. just saying not to go around and totally say all models are wrong and will amount to nothing is wrong. I'm agreeing with him..Everyone was all liking the chances of a storm before the 18z GFS came and bam negative thoughts and such. Man I've been a lurker for a few weeks(even tho i reg in JAN) and am not liking this forum at all. Link to comment Share on other sites More sharing options...
CT Rain Posted October 22, 2012 Author Share Posted October 22, 2012 I'm agreeing with him..Everyone was all liking the chances of a storm before the 18z GFS came and bam negative thoughts and such. Man I've been a lurker for a few weeks(even tho i reg in JAN) and am not liking this forum at all. Wait... people were "liking" the storm chances for a 180-200 hour forecast? Link to comment Share on other sites More sharing options...
CoastalWx Posted October 22, 2012 Share Posted October 22, 2012 im not saying to hype it. nowhere did i say that in my post. just saying not to go around and totally say all models are wrong and will amount to nothing is wrong. Some models are also not showing it. But, that isn't the point and I didn't mean to infer that you were hyping. You have to understand that some of those solutions would be extremely rare. They are anomalous for a reason...they simply don't happen often. It's wise to expect a more realistic outcome and that's what we are saying. It's not impossible for it to be a much higher impact...the modeled H5 pattern could support something very anomalous...but you are setting yourself up to be disappointed if you expect something close to the 12z Euro or GFS. Even something in between has a much higher chance of occurring. Link to comment Share on other sites More sharing options...
ORH_wxman Posted October 22, 2012 Share Posted October 22, 2012 The pattern looks favorable for some sort of storminess...but people need to remember that doesn't mean a Hazel redux or whatever...it could easily be just the PJ troughiness digging in and giving a run of the mill coastal or a graze with rainy weather. There's a difference between saying the pattern overall may favor some storminess and that we are looking at a massive high-impact 1 in 50 year event. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.