am19psu Posted May 7, 2013 Share Posted May 7, 2013 Is anyone worried about the NAO going negative? In about 6 to 10 days, -u anomalies will be attacking the polar latitudes from 2 sources: the final warming's polar vortex destruction and the poleward AAM anomalies. The final warming originating at 1 hpa is a little less typical than the usual starting point (10 hpa) and doesn't have the same correlations with the NAO/AO as the 10 hpa warmings do. Either way, if we see an enhancement of westerly 30-40N flow and easterly around 60N, there could be issues with getting any warmth sustained for us through early-mid June. Link to comment Share on other sites More sharing options...
NaoPos Posted May 7, 2013 Share Posted May 7, 2013 12z gfs op is a horror story for the heat meisers: Pretty much looks like that in the med-long range. 12z gefs agree: West coast ridge dropping down vorts into the east central conus, and bc of the ridging in eastern Canada, they amplify and cut off. No SE ridge being modeled. This isn't a forecast by me, just pointing out what the gefs/gfs are showing. It does fit the mold of the current wether pattern. Link to comment Share on other sites More sharing options...
HM Posted May 7, 2013 Author Share Posted May 7, 2013 The thing that we know is most likely to be a real signal at this point is the retograding Gulf of Alaskan Low. It should arrive at the Aleutians by day 10. It is going to be rather difficult to hold that pattern once this occurs as each new s/w is going to be able to dig sooner. So while the first one goes screaming along the US-Canadian border next week, the next one should be able to be solidly embedded within the US. With the broad anticyclone over the 4-corners/SW Plains, we have to anticipate the potential for an eastern US cutoff. But having said that, I can't quite buy something as extreme as the GFS 12z solution. The entire polar field / westerlies will be in the process of contracting the next 10 days which fits with the current AAM regime. How quickly this alters and when is a big question. Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted May 7, 2013 Share Posted May 7, 2013 HM, May snow? Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted May 8, 2013 Share Posted May 8, 2013 chilly gfs numbers on gfs 0z Link to comment Share on other sites More sharing options...
tombo82685 Posted May 8, 2013 Share Posted May 8, 2013 chilly gfs numbers on gfs 0z you know they have quakertown for the meteogram to Link to comment Share on other sites More sharing options...
Quakertown needs snow Posted May 8, 2013 Share Posted May 8, 2013 yes but abe is chiller i miss your snow avatar Link to comment Share on other sites More sharing options...
HM Posted May 8, 2013 Author Share Posted May 8, 2013 HM, May snow? I couldn't get us snow in April so why not!? The mid-section of the nation has been hogging all the spring snowfall. I love how zonal the 00z ECMWF looks. I haven't seen a zonal ECMWF run in the extended in a long time! <<<going by memory. Link to comment Share on other sites More sharing options...
tombo82685 Posted May 8, 2013 Share Posted May 8, 2013 Any shot of some good storms friday afternoon? Gfs timing of the front looks like after dinner sometime. Shear looks alright, but the cape and LI look rather weak. Maybe shear induced storms? The euro's timing looks to be later towards the morning on saturday, which would diminish the risk obviously. Link to comment Share on other sites More sharing options...
NaoPos Posted May 8, 2013 Share Posted May 8, 2013 Any shot of some good storms friday afternoon? Gfs timing of the front looks like after dinner sometime. Shear looks alright, but the cape and LI look rather weak. Maybe shear induced storms? The euro's timing looks to be later towards the morning on saturday, which would diminish the risk obviously. Check out the banter thread, me and HM added some things in there. 12z euro goes bonkers with the -NAO and west coast ridging. Where was this 3 months ago.... Link to comment Share on other sites More sharing options...
Mike.Ventrice Posted May 9, 2013 Share Posted May 9, 2013 Check out the banter thread, me and HM added some things in there. 12z euro goes bonkers with the -NAO and west coast ridging. Where was this 3 months ago.... The Euro op killed the -NAO in the 00z this morning... The ensembles don't really support the -NAO developing.. how do you guys feel about this? Link to comment Share on other sites More sharing options...
tombo82685 Posted May 9, 2013 Share Posted May 9, 2013 The Euro op killed the -NAO in the 00z this morning... The ensembles don't really support the -NAO developing.. how do you guys feel about this? Doesn't phase 3-5 on the mjo show some sort of -nao symbol? Link to comment Share on other sites More sharing options...
ptb127 Posted May 9, 2013 Share Posted May 9, 2013 The stratosphere doesn't really support a -NAO either.. I feel pretty good about no -NAO The Euro op killed the -NAO in the 00z this morning... The ensembles don't really support the -NAO developing.. how do you guys feel about this? Link to comment Share on other sites More sharing options...
HM Posted May 9, 2013 Author Share Posted May 9, 2013 Look, I follow the logic, I do, for why the ECMWF -NAO run was false. Even today's 12z GGEM is probably overdone too. But there are anticyclones positioned, in the means, on either side of the PV in the N Atlantic in the extended range. They may occasionally "ridge bridge" across Greenland but I think the GGEM went overboard before day 10. However, saying that the NAO stays positive might be a mistake here, especially if you are basing this on the stratosphere (actualy -u winds will be taking over from top to bottom). I think the pseudo west based -NAO setup could briefly turn rather anomalous/more classic at the end of the month and lock the trough over the Northeast. Link to comment Share on other sites More sharing options...
Mike.Ventrice Posted May 10, 2013 Share Posted May 10, 2013 Look, I follow the logic, I do, for why the ECMWF -NAO run was false. Even today's 12z GGEM is probably overdone too. But there are anticyclones positioned, in the means, on either side of the PV in the N Atlantic in the extended range. They may occasionally "ridge bridge" across Greenland but I think the GGEM went overboard before day 10. However, saying that the NAO stays positive might be a mistake here, especially if you are basing this on the stratosphere (actualy -u winds will be taking over from top to bottom). I think the pseudo west based -NAO setup could briefly turn rather anomalous/more classic at the end of the month and lock the trough over the Northeast. I think your on to something HM.. I favored my forecast to more of a negative NAO at the end of Week 2, but feel better about it by Week 3 for sure. Thanks for your advice here. Link to comment Share on other sites More sharing options...
Mike.Ventrice Posted May 10, 2013 Share Posted May 10, 2013 Doesn't phase 3-5 on the mjo show some sort of -nao symbol? It does, but the MJO hasn't really impacted the extra-tropical circulation over the N. Hemisphere yet. Also in 2 weeks, I'd expect the MJO to be over the West Pacific so we'd be more in a Phase 5-6 ish state- but still how much does the MJO influence the extra-tropics during Spring? I feel that processes associated with the Polar Vortex are more important during Spring/Fall than MJO forcing (which is the greatest during boreal winter). Link to comment Share on other sites More sharing options...
am19psu Posted May 10, 2013 Share Posted May 10, 2013 I think your on to something HM.. I favored my forecast to more of a negative NAO at the end of Week 2, but feel better about it by Week 3 for sure. Thanks for your advice here. Definitely agree with this. Memorial Day Weekend looks like a lock to be in a -NAO state. I think next weekend has more uncertainty in it. Link to comment Share on other sites More sharing options...
am19psu Posted May 10, 2013 Share Posted May 10, 2013 It does, but the MJO hasn't really impacted the extra-tropical circulation over the N. Hemisphere yet. Also in 2 weeks, I'd expect the MJO to be over the West Pacific so we'd be more in a Phase 5-6 ish state- but still how much does the MJO influence the extra-tropics during Spring? I feel that processes associated with the Polar Vortex are more important during Spring/Fall than MJO forcing (which is the greatest during boreal winter). Yep, definitely true, as well. That said, tropical forcing can certainly increase the strength of the subtropical highs, which is why p5 and esp p6 can have some influence here. Link to comment Share on other sites More sharing options...
BxEngine Posted May 10, 2013 Share Posted May 10, 2013 Hope you guys dont mind the intrusion for whats probably a dumb question...but can a -nao help promote decent weather in the northeast during spring? Link to comment Share on other sites More sharing options...
am19psu Posted May 10, 2013 Share Posted May 10, 2013 Hope you guys dont mind the intrusion for whats probably a dumb question...but can a -nao help promote decent weather in the northeast during spring? It can, especially the farther north you're located and the more the -NAO is west based (see e.g. last week) Link to comment Share on other sites More sharing options...
NaoPos Posted May 10, 2013 Share Posted May 10, 2013 Look, I follow the logic, I do, for why the ECMWF -NAO run was false. Even today's 12z GGEM is probably overdone too. But there are anticyclones positioned, in the means, on either side of the PV in the N Atlantic in the extended range. They may occasionally "ridge bridge" across Greenland but I think the GGEM went overboard before day 10. However, saying that the NAO stays positive might be a mistake here, especially if you are basing this on the stratosphere (actualy -u winds will be taking over from top to bottom). I think the pseudo west based -NAO setup could briefly turn rather anomalous/more classic at the end of the month and lock the trough over the Northeast. Sounds comfy. Death to SE RIDGES! Link to comment Share on other sites More sharing options...
CoastalWx Posted May 11, 2013 Share Posted May 11, 2013 Nocturnal sizzle for some of y'all Thursday Night? Link to comment Share on other sites More sharing options...
NaoPos Posted May 16, 2013 Share Posted May 16, 2013 what a ridge! Link to comment Share on other sites More sharing options...
ptb127 Posted May 17, 2013 Share Posted May 17, 2013 Hopefully that moves east!!! Link to comment Share on other sites More sharing options...
NaoPos Posted May 18, 2013 Share Posted May 18, 2013 Seems to me, that the driver of all this seasonable weather is the +NAO. The low height anomolies over Greenland seem to have created a maritime Hp over the Natlantic, putting us under a marine influence/ BDCF scenario this spring. Is it safe to assume that? 0z euro shows it's quite well. Link to comment Share on other sites More sharing options...
tombo82685 Posted May 20, 2013 Share Posted May 20, 2013 What is driving the big heat in the extended range 240hrs out? I see its the -pna pumping the ridge, and the nao is slightly pos but the mjo forecast has it going into COD then phase 1. Doesn't this favor more of a pos pna look for late may into early june? To me it looks like the heat would be focused after the first week of june based on mjo forecast. The euro days 8-10 have the backdoor cold front look to it, while the heat stays bottled up in the mid west. Link to comment Share on other sites More sharing options...
am19psu Posted May 20, 2013 Share Posted May 20, 2013 Don't see much in the teleconnections with the MJO. Kinda fizzles after this week, imo. Looks fairly progressive with little in the way of obvious "unusual" forcing. Warm followed by cool followed by warm. Rinse and repeat. Link to comment Share on other sites More sharing options...
NJwinter23 Posted May 20, 2013 Share Posted May 20, 2013 It seems like we are setting up a nice home base for heat to start the summer, western plains and intermountain which would make sense for some drought feedback as well. Warm look in general for the East to start June but i'd think any hotter spikes coming out of the plains would be short-lived given the pattern, versus any extended heat waves in this neck of the woods. Link to comment Share on other sites More sharing options...
tombo82685 Posted May 23, 2013 Share Posted May 23, 2013 0z euro is starting to bite on the heat in the 8-10 day period. 0Z had 90-95 towards the end. Link to comment Share on other sites More sharing options...
ptb127 Posted May 24, 2013 Share Posted May 24, 2013 12z euro continued that trend from 0z.. GFS is a little cooler but on board too. Looking forward to it! Link to comment Share on other sites More sharing options...
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