Winter 2014-2015 Pattern Discussion Thread I

[franklin NCwx]

Wow!! Welcome webberwx.

[MichaelJ]

I just looked at it. With all due respect to DT, I think it will verify much colder for the SE for DJF than he has. He's predicting a weak El Nino, solid +PDO, solid -AO, and solid -NAO and yet he has DJF averaging near normal temp.'s for nearly all of the SE. Also, I'm guessing he's too dry along the Gulf coast though I'm not as confident about that as I am about temp.'s. El Nino's favor the wettest there and then up the E coast. He's ok along the east coast but he's predicting near to slightly below normal for the Gulf coast. That doesn't fit Nino climo too well.

I agree with this post. Welcome aboard to Webber, nice to have another poster who also happens to know his/her stuff.

[LithiaWx]

welcome aboard Webber. Those are some incredible posts, thank you for your contribution. Looking forward to more. Thank you.

[deltadog03]

Thanks! I hope I will be able to make significant contributions over the coming winter when a winter storm actually strikes...

Nope...no snow this year..hahah

[dsaur]

Good posts, Webber. We usually try to encourage all new posters to start storm threads for 15+ day events, but I guess we can make an exception in this case. Seriously, welcome aboard! And thanks for dropping some knowledge.

Like night and day, isn't it  

Welcome Mr. Webber, nice to see more class up in this joint   T

[dsaur]

I just looked at it. With all due respect to DT, I think it will verify much colder for the SE for DJF overall than he has. He's predicting a weak El Nino, solid +PDO, solid -AO, and solid -NAO and yet he has DJF averaging near normal temp.'s for nearly all of the SE. Also, I'm guessing he's too dry along the Gulf coast though I'm not as confident about that as I am about temp.'s. El Nino's favor the wettest there and then up the E coast. He's ok along the east coast but he's predicting near to slightly below normal for the Gulf coast. That doesn't fit Nino climo too well.

It's because, like so many others, he thinks the south ends at I 20, and when you average in how cold I'll be down here,  Where There Be Monsters, we'll come out a lot colder

   I'm going to note how many nights I get rain this month, vs how many nights I hit 32, which won't really be accurate as it can snow up to 40, or so if conditions are right, but I'm curious if we needed more cold at the end of Dec, or more rain....to go with the necessary timing. T

[griteater]

Thanks griteater, I really enjoyed your winter outlook BTW... Ironically, I was just about to post that article, lol. He is eons ahead of me in terms of meteorological knowledge and I've already learned a substantial amount of information from him just through periodic interactions on twitter. Hopefully, I will be able to attain that kind of robust knowledge base someday...

 

Thanks, I appreciate it...I just hope we can celebrate verification come March  

[BIG FROSTY]

Welcome aboard, webber! Awesome posts. Looking forward to more of your posts this winter.

[DaculaWeather]

Thanks guys, & I am not going to lie, Chris one of the nicest people I've met through social media thus far & appreciate all of the complements from everyone. As far as this weak correlation between multi year El Nino events & the following winter AO goes, I have tried to isolate a few variables to distinguish confounding factors & what I have noticed is that several months in advance of the winter, even before we begin to monitor the SAI/SCE in October, there's a definitive SST signal within the Kurioshio-Oyashio Extension (KOE) & North Pacific Current east of Japan and east of Newfoundland. Subtracting off the SST in the top 10 + vs -AO winters reveals the largest difference in SSTs in & around 40N (once again), with cooler waters being associated more so with a -AO in the subsequent winter, reason being the cool SST in the mid-latitudes feedback to lower heights & at this "critical" latitude in & around 40N this encourages the jet to extend its nose equatorward & because these cool SSTs were at least partially implemented by wind stress via passing cyclones, we can conclude the cool SSTs in this latitudinal band serve as a proxy for an extensive mid-latitude jet that encourages undercutting & high latitude blocking.

 

September SSTs preceding the top 10 +AO vs -AO El Nino Winters...

 

Now look at this year in mid september, you can clearly see the tongue of cool water already manifesting itself ~ 40N in both the Atlantic & Pacific a few weeks *before* we started to monitor the SAI

 

 

 

 

Similar image to the first one, except I flipped the years being subtracted & extended this over the entire globe for the SON tri-monthly period, thus we should see a warm tongue of SST in the KOE/ N Pac Current...

 

 

Now, I expanded this analysis of the AO to all winters & the results weren't quite as convincing...

 

 

I then excluded neutral events & lo & behold the SST signal actually intensified...

 

 

Upon seeing this, I suppose that intraseasonal forcing from the MJO may be somewhat at fault here. I've read in several pieces of literature that note the MJO tends to generally propagate more freely in the absence of a significant ENSO event, which leads me to think that w/o low frequency ENSO state predominantly favoring anomalous jet extension (El Nino) or retraction into the Eastern Hemisphere (La Nina), I postulate things can become quite convoluted w/ intraseasonal modulation by the MJO possibly promoting increased variance of the Pacific Jet & hence this relationship to the SSTs begins to fall apart, but this is merely a hypothesis at this point...

 

Great post Eric! Glad to see you posting! :-)

[FallsLake]

The 0z and 6z GFS are ugly in the LR. Not a torch but definitely above normal temps across much of the US. The only thing that saves the SE is the temps compared to average will not be as high as folks farther north (..which will be calling this a torch). We may even get a few days of normal or even below normal temps, if lucky.

[packbacker]

The 0z and 6z GFS are ugly in the LR. Not a torch but definitely above normal temps across much of the US. The only thing that saves the SE is the temps compared to average will not be as high as folks farther north (..which will be calling this a torch). We may even get a few days of normal or even below normal temps, if lucky.

 

Lovely...going to put some pre-emergent down this week.

 

Edit:  Finally looking at the Euro Op, it's mildly interesting mid next week, big HP sliding east, similar to what is happening tomorrow.  So the MA/NE may get another little winter event.

[Webberweather53]

Thanks again everyone, I certainly feel very welcome here & am glad I joined the discussion.

 

The JTWC has upgraded invest 95W in the West Pac to Tropical Storm 22 & it should get named Hagupit (if it hasn't done so by the time you're reading this post), and their current intensity forecast only calls for the storm to reach a max intensity of 105 knots, but knowing behavior of storms in this basin & the JTWC's conservative nature, I would be inclined to think we'll see a much stronger typhoon emerge over the next several days...

 

A few notes on this system, it has received a huge boost from the passage of the convectively enhanced phase of the Equatorial Convectively Coupled Kelvin Wave & especially the westward propagating equatorial Rossby Wave, and with the upward phase of the MJO approaching, from an equatorial wave standpoint, conditions look quite favorable for strengthening of TS 22. You can track the progress of these various equatorial waves at Carl Schreck's monitoring page...

http://monitor.cicsnc.org/mjo/current/

 

Also, it has formed particularly far to the south & east in the western Pacific, and this isn't all too uncommon in an El Nino as we typically see w/ the weakening & eastward shift of the Walker Cell, a coincident eastward shift also occurs with the equatorial trough, where moist monsoon southwesterlies meet up with the easterly trades, forming a natural region of enhanced vorticity & convergence that is supportive of tropical cyclone formation, and this becomes most evident the further away you get from the peak of the hurricane season when the monsoon trough is typically positioned further away from southeast Asia.

 

A picture found on page 309 from a paper published in 2004 by Pao-Shin Chu describing the effects of ENSO on global tropical cyclone activity, (it's a fairly easy read, IMO). http://www.soest.hawaii.edu/MET/Hsco/publications/2004.2.pdf showing the shift in tropical cyclone genesis points between the top 6 yrs w/ the highest & lowest SST in the NINO 3.4 region. The most significant difference in basin activity appears to be in the far eastern portion of the West Pacific basin (along/east of 150E), where the formation of storms in El Nino years tend to dominate...

Levi Cowan posted this at least a year or so ago & its one of the best graphics, IMO that presents this southeastward displacement in Western Pacific typhoon tracks in the top 10 El Ninos. Since storms form further out into the central Pacific closer to the dateline they have more time to strengthen & a better opportunity to recurve into the typically stronger troughs that emerge from eastern Asia...

 

I certainly think the main focus for North American meteorologists & forecasts will be on the recurvature of TS 22, and here's a nice picture which graphically describes the Western Pacific Typhoon Teleconnection for those who may be unfamiliar. Notice how the typhoon causes extension/excitation of the Pacific jet as its upper level outflow merges w/ & intensifies the waveguide (the mid-latitude jet) (this is very analogous to what we often observe with the damping (decrease in amplitude) of transverse (waves traveling perpendicular to the mean flow, like gravity waves for ex) tropospheric waves (in this case I'm specifically referring to the equatorial Kelvin & Mixed Rossby Gravity Waves) as they disperse their energy & momentum through the tropopause & into the stratosphere, generating a force on the mean westerly flow, which has implications on the maintenance of the QBO & polar vortex). This extension of the Pacific jet, in the left exit region of the leads to large-scale divergence in the upper levels as air escapes generally poleward, thus favoring cyclogenesis in this area in & around the Aleutians. The Aleutian trough causes the heights to subsequently rise over western North America & a trough then digs east of the Rockies, leading to at least a brief stint cooler & stormier weather here. We may not see this teleconnection come into play until at least the 3rd week of December...

 

I'm sure this information will come in handy to some over the coming few weeks, so here's Archambault's super-massive 200 page doctoral thesis on "The Downstream Extratropical Flow Response To Recurving Western North Pacific Tropical Cyclones"

http://www.atmos.albany.edu/student/heathera/dissertation/archambault_dissertation.pdf

[FallsLake]

Hay Webber, so your saying the storm is a product of the pattern. Will we have to depend on storms (like this) to (constantly) flip the pattern in our favor.  

[Cold Rain]

This is an interesting look.  I really like seeing these strong highs tracking across the northern tier already this year.  Should this continue through the season, much winter fun lies ahead:

 

[El Kabong]

Wow...way to make a big splash, Webber!  You may have just won the grand prize for best first-time posts.  It's great to have another excellent member with some high weather IQ in the SE forum.  I have a short list of forum members whose posts I pay special attention to.  Your name will definitely be added to the list.  Welcome aboard!

[GaStorm]

Webber, you are a great addition to the board and to the SE forum! Thanks for the informative posts!

[buckeyefan1]

I could see us having to sacrifice December, MOST** of it.  Not all.  Either way, I would rather punt for DEC and have a rocking JAN/FEB  no offense to anyone, but DEC is great, but JAN and FEB *and hell even MAR* have more potential for most. 

 Hasn't that been the plan since October?     

 

I completely disagree. I would much rather have a rocking Dec than Jan or Feb. There's just something about cold and snow around Christmas time that makes it seem more magical.

Even when I lived in Ohio this was not a given, besides.... we've already had our Christmas miracle for this lifetime          

 

Thanks! I hope I will be able to make significant contributions over the coming winter when a winter storm actually strikes...

Welcome Eric!    

 

This is an interesting look.  I really like seeing these strong highs tracking across the northern tier already this year.  Should this continue through the season, much winter fun lies ahead:

 

f216.gif

I agree with the bolded  

[NCSNOW]

Looks like TS 22 is gonna set the table up from mid Dec to mid Jan just like the big pac tc did giving us the November to remember. This has to be one.of the most encouraging things to monitor this week. We want benefit from it for another couple weeks and the LR models won't figure it out for a while, but webber and Robert last night on his website have discussed the domino effect that should take place after TS 22 races off to the NE across the pac latter this week into next. Now to get the stj going by mid month and in split flow fashion some fun and games could be just around the corner.

[Cold Rain]

Neither the 12z GFS nor the 12z Euro offer much in the way of winter through the next 10 days (or beyond, in the case of the GFS).  Both continue to support a low anomaly in or near the GOA and a fairly benign pattern across the US.  The 10C 850 line never really makes it north of southern GA through the period, so temps don't really look to torch.  The Euro has a nice +PNA, but it's a good example of how a +PNA doesn't really result in cold, wintry weather, as there is no real cold air being tapped.  That low anomaly needs to retrograde west.

[GaWx]

Neither the 12z GFS nor the 12z Euro offer much in the way of winter through the next 10 days (or beyond, in the case of the GFS).  Both continue to support a low anomaly in or near the GOA and a fairly benign pattern across the US.  The 10C 850 line never really makes it north of southern GA through the period, so temps don't really look to torch.  The Euro has a nice +PNA, but it's a good example of how a +PNA doesn't really result in cold, wintry weather, as there is no real cold air being tapped.  That low anomaly needs to retrograde west.

 

CR,

 Per my source, the 12Z Euro actually has below normal temp.'s for the SE in the 6-10 with that +PNA and an Arctic high bringing cold/below normal temp.'s 12/9-11! Highs are only in the 40's 12/9-10 and lows are in the 20's 12/10-11. Yet, all I seem to hear is warm talk from some. (not from you).

 

Edit: this cold wasn't even showing up all that well as recently as the 12Z Euro of yesterday.

[packbacker]

CR,

 Per my source, the 12Z Euro actually has below normal temp.'s for the SE in the 6-10 with that +PNA and an Arctic high bringing cold/below normal temp.'s 12/9-11! Highs are only in the 40's 12/9-10 and lows are in the 20's 12/10-11. Yet, all I seem to hear is warm talk from some. (not from you).

 

Edit: this cold wasn't even showing up all that well as recently as the 12Z Euro of yesterday.

 

One thing that is happening on these models is you have big HP rolling through, so you do cool off but it rolls on through and then warms up.  Keep this up and throw in some blocking it would be scary...

[RONALD B]

One thing that is happening on these models is you have big HP rolling through, so you do cool off but it rolls on through and then warms up.  Keep this up and throw in some blocking it would be scary...

https://twitter.com/WxSouth/status/539411923146915840/photo/1 robert seems too like the set up in the long range . The pna will go thou the roof we need  some blocking hopefully models will trend ?

[JoMo]

Neither the 12z GFS nor the 12z Euro offer much in the way of winter through the next 10 days (or beyond, in the case of the GFS).  Both continue to support a low anomaly in or near the GOA and a fairly benign pattern across the US.  The 10C 850 line never really makes it north of southern GA through the period, so temps don't really look to torch.  The Euro has a nice +PNA, but it's a good example of how a +PNA doesn't really result in cold, wintry weather, as there is no real cold air being tapped.  That low anomaly needs to retrograde west.

 

12z Euro actually has below normal temps for the SE Tues through Thurs (end of run) of next week. Looks like a general 8 degrees or so below normal as an average.

[Cold Rain]

Thanks GA and PB!  That's what I've been encouraged about...the HPs sliding across the north.  There's no real cross-polar flow or anything frigid in the pipeline yet, but an all out torch is not looking likely.  Still no real shot at winter weather but it's not important right now.  We just need the pattern to progress.

 

In the meantime, maybe we should create a new section for the SE called Torch Talk, where we discuss all the ways it is imminently going to warm up.  Then, later on, while we wait for the warm up, we can post pictures of the snow Polar Party section.

[Brick Tamland]

One thing that is happening on these models is you have big HP rolling through, so you do cool off but it rolls on through and then warms up.  Keep this up and throw in some blocking it would be scary...

 

I think that is what a lot of mets and posters calling for a big winter are counting on.

[Cold Rain]

12z Euro actually has below normal temps for the SE Tues through Thurs (end of run) of next week. Looks like a general 8 degrees or so below normal as an average.

 

That's awesome.  I was just eyeballing the 850s from the ewall page.  But like Larry said, I'm not sure where all the heatwave talk is coming from.  Maybe the CFS?

[packbacker]

That's awesome. I was just eyeballing the 850s from the ewall page. But like Larry said, I'm not sure where all the heatwave talk is coming from. Maybe the CFS?

Weeklies released in a couple of hours, fully expect week 3 to look better and week 4 to be game on, stout -NAO/-AO.

[Cold Rain]

who are you?

 

A person who is about to be sorely disappointed.  Mwhahaha!

 

That big low off the NW coast is bothering me.

[Snowless in Carrollton]

Thanks GA and PB! That's what I've been encouraged about...the HPs sliding across the north. There's no real cross-polar flow or anything frigid in the pipeline yet, but an all out torch is not looking likely. Still no real shot at winter weather but it's not important right now. We just need the pattern to progress.

In the meantime, maybe we should create a new section for the SE called Torch Talk, where we discuss all the ways it is imminently going to warm up. Then, later on, while we wait for the warm up, we can post pictures of the snow Polar Party section.

you don't call an extended period of 10+ above normal a torch ? 70s today, upper 60s the rest of the week. The first week of December will average close to 10 degrees above normal. That's a torch to me.

[Brick Tamland]

you don't call an extended period of 10+ above normal a torch ? 70s today, upper 60s the rest of the week. The first week of December will average close to 10 degrees above normal. That's a torch to me.

 

We have had plenty of weeks like that here in winter followed by big snow storms. Doesn't concern me.