Winter 2014-2015 Pattern Discussion Thread II

[Brick Tamland]

As I've stated before I think our best chance for wintery precip will be the end of January into the first two weeks of February. The only reason I can give (other than gut feeling) is from past readings about how the pattern usually flips to an opposite configuration(from the dominate winter pattern) during mid winter. Either this is a mid winter thaw or a mid winter cold snap.

 

I think 1999-2000 was a similar winter where it was warm up until the last part of January. The pattern got cold and we ended up with this:

 

http://www4.ncsu.edu/~nwsfo/storage/cases/20000125/

 

Not saying we'll get a major storm but  think this will be the most favorable time period.    

 

The last 10 to 15 days of January seem to be special for us around these parts. A lot of good snows during that time period. I also like this part of the case study.

 

.The storm was not well forecast by numerical weather prediction models...

...Following the event, research at NC State indicated that the inability of the operational models to resolve antecedent precipitation across the Deep South was a major reason for their forecast failure of the developing cyclone...

...This event reinforces the need for forecasters to maintain situational awareness of upstream conditions and to compare model forecasts with observations...

[burgertime]

The last 10 to 15 days of January seem to be special for us around these parts. A lot of good snows during that time period. I also like this part of the case study.

 

.The storm was not well forecast by numerical weather prediction models...

...Following the event, research at NC State indicated that the inability of the operational models to resolve antecedent precipitation across the Deep South was a major reason for their forecast failure of the developing cyclone...

...This event reinforces the need for forecasters to maintain situational awareness of upstream conditions and to compare model forecasts with observations...

 

This was practically 15 years ago. Doubt models would miss this now with how good they have gotten especially in the short term. 

[Cold Rain]

As we close the books on 2014 and stumble headlong into the new year, January looks to start off with a bang! The LR pattern is looking good and snow prospects should pick up as we head through the month.

So first off, I'd like to offer up Exhibit A, the 240 0z Euro. As you can see, Canada is nice and cold and the US is precariously positioned underneath the motherload, ready to be dumped on at any time (as you can clearly see by the tell-tale coast to coast frowny face pattern:

Next up, I'd like to submit into evidence Exhibit B, the 372 hr 0z GFS. Cold has dumped into the western US underneath the favorable smiley face pattern across the north. However, the cold has been forestalled indefinitely by the non-SE ridge-like-type feature not existing over and off of the SE coast:

Next, take a look at Exhibit C, the 0z Navgem at 120. You can clearly see Canada quite cool with cold again dumping into the western US. The non-SE ridge-like-type non-feature is blocking the cold from spilling east, as evidenced by the gun-to-head pattern that has set up shop over northern Canada:

The last operational model run to be submitted into evidence is Exhibit D, the 108 hr Canadian eh. You can clearly see the high pressure ridge extending off the NE coast, a hallmark of the bird poop pattern over central Canada extending down into the US:

Exhibit E features a collage of indexes. The mountainous AO overlays an optimistic NAO and Atlantis-type PNA configuration:

Continuing, we clearly see in Exhibit F the beloved High Five MJO forecast pattern, which is not important at all to the overall evolution of the pattern. I don't even know why I'm including it:

For our next to last piece of evidence, I'd like to submit Exhibit G, the equatorial Pacific SST chart, showcasing the popular pee-stain pattern, with some wind anomalies for good measure:

Finally, for Exhibit H, here is the latest CFS for January. It clearly shows the middle finger pattern that is loved by virtually all east coast snow geese:

Happy New Year!!

[packbacker]

Jan 2000 had the NAO and AO go negative for about 10 days which is why we got a couple of events. Yeah the pattern sucked but we would still need blocking which no model shows happening. Only thing showing blocking is past analogs and those have all since busted.

[Isopycnic]

As we close the books on 2014 and stumble headlong into the new year, January looks to start off with a bang! The LR pattern is looking good and snow prospects should pick up as we head through the month.

So first off, I'd like to offer up Exhibit A, the 240 0z Euro. As you can see, Canada is nice and cold and the US is precariously positioned underneath the motherload, ready to be dumped on at any time (as you can clearly see by the tell-tale coast to coast frowny face pattern:

Euro240a.jpg

Next up, I'd like to submit into evidence Exhibit B, the 372 hr 0z GFS. Cold has dumped into the western US underneath the favorable smiley face pattern across the north. However, the cold has been forestalled indefinitely by the non-SE ridge-like-type feature not existing over and off of the SE coast:

GFSf372.gif

Next, take a look at Exhibit C, the 0z Navgem at 120. You can clearly see Canada quite cool with cold again dumping into the western US. The non-SE ridge-like-type non-feature is blocking the cold from spilling east, as evidenced by the gun-to-head pattern that has set up shop over northern Canada:

Navgem120.gif

The last operational model run to be submitted into evidence is Exhibit D, the 108 hr Canadian eh. You can clearly see the high pressure ridge extending off the NE coast, a hallmark of the bird poop pattern over central Canada extending down into the US:

CMCf108.gif

Exhibit E features a collage of indexes. The mountainous AO overlays an optimistic NAO and Atlantis-type PNA configuration:

ao_sprd2.gif

Continuing, we clearly see in Exhibit F the beloved High Five MJO forecast pattern, which is not important at all to the overall evolution of the pattern. I don't even know why I'm including it:

ECMF_phase_51m_small.gif

For our next to last piece of evidence, I'd like to submit Exhibit G, the equatorial Pacific SST chart, showcasing the popular pee-stain pattern, with some wind anomalies for good measure:

sstweek_c.jpg

Finally, for Exhibit H, here is the latest CFS for January. It clearly shows the middle finger pattern that is loved by virtually all east coast snow geese:

New Bitmap Image.jpg

Happy New Year!!

Clearly Exhibit H is weather weenie and not a middle finger.

 

 

[Brick Tamland]

Yeah, I guess there's no reason for Huffman and East to say what they did today. 

[packbacker]

Great post CR! The SE ridge this year will have staying power like -EPO from last year.

[SnowNiner]

 

 

Matthew East

4 mins · 

Long term pattern.... I think the models are just beginning to sniff out some of the potential for periodic waves of Jan. cold. We will see.

 

 

That's encouraging, though I'm wondering what specifically he's looking at to think that the models are starting to sniff it out.  I don't see anything good in the long range really.  On the 6Z gfs the PNA looks ok with a nice tall ridge....and even some higher heights over greenland....but it was just one run of the gfs (looooong range). 

 

[SnowNiner]

Great post CR! The SE ridge this year will have staying power like -EPO from last year.

 

You mean the not really, kinda acting like, it looks like a ridge but it's not....SE ridge?  I think that element will go and come based on where the pacific ridge (true ridge?) sets up.  If we get that in the right place on the coast causing a trough in the east, that "ridge" will naturally go away/move.  I doubt it's a fixed feature IMO.

[packbacker]

You mean the not really, kinda acting like, it looks like a ridge but it's not....SE ridge? I think that element will go and come based on where the pacific ridge (true ridge?) sets up. If we get that in the right place on the coast causing a trough in the east, that "ridge" will naturally go away/move. I doubt it's a fixed feature IMO.

It's a SE ridge.

We get blocking it will go away.

[franklin NCwx]

Great post CR! The SE ridge this year will have staying power like -EPO from last year.

the se ridge has briefly made an appearance. Those high heights you see in the east past day 10 is from the western ridge getting shoved east.

[Webberweather53]

 

ATL: major ZR's since 1974: all when the MJO was within the COD

 

2/6-7/1979

1/22-23/2000

1/28-30/2000

1/28-9/2005

12/14-5/2005

2/12/2014

 

 

I looked around for correlations between 200VP, SLP, OLR, Streamfunction, Vector Winds, etc, and although I was picking up on signals that resembled the eastern hemisphere (phase 2-4) MJO, I am afraid any attribution to Eq Waves is hampered by not only the lack of events I had to work w/, but the stout cold ENSO in all of these years likely contaminated any viable overall signaling I could have attained, but thanks anyway, it was worth a shot...

 

The problem is that map might change in a few days    .  I thought all indications pointed towards less of a Modoki El Nino and more towards a weak El Nino? 

 

 

The two are correlated, but there isn't a 1-1 relation. In fact, the correlation to the maximum ONI tri-monthly intensity & placement of the near equatorial warmest SSTs anomalies is weakly negative at best, w/ coefficient of determination around .18 (or 18% of the variance in El Nino placement can be attributed to its intensity, huge red flag to a multitude of hidden/lurking variables... )

 

The weaker El Nino events are more susceptible to succumbing to equatorial upwelling off South America & intraseasonal Kelvin Wave variance which can dramatically alter the relatively weaker signaling in thermocline and SSTs. The larger region of +SSTs & higher amplitude of those anomalies in stronger events make them less prone to this variance that operates at a higher frequency than the ENSO index itself, and thus are more likely to be traditional or hybrid events with at the very least residual +anoms in the NINO 1-2 region & the warmest water vs average in the east (NINO 1-2) (traditional) or east-central (NINO 3 &/or 4) equatorial Pacific. However, the profound amount of internal variation among individual El Ninos (particularly in the Hybrids (East-Central Based years), even those w/ the same classification based on SSTs, causes substantial weakening in the correlation between El Nino intensity & placement. You'd likely find a more robust relationship comparing the El Nino intensity to the naturally more volatile NINO 1-2 region...

 

Traditional (EB) El Nino DJF SSTs

 

Hybrid (E-CB) El Ninos DJF Equatorial Pacific SSTs 

Modoki (CB) El Nino DJF Equatorial Pacific SSTs

 

[franklin NCwx]

Soi is -10 today, it's slowly been trending negative hopefully it will continue.

[Cold Rain]

Who really cares what it is or isn't. We aint getting no snow with a trough in the west and a ridge in the east.

[burgertime]

As we close the books on 2014 and stumble headlong into the new year, January looks to start off with a bang! The LR pattern is looking good and snow prospects should pick up as we head through the month.

Happy New Year!!

 

 

 

 

You forgot to submit the SSW into evidence. 

[Cold Rain]

You forgot to submit the SSW into evidence.

I don't have those maps handy. Nice Columbo reference!!

[GaWx]

Webber,

Thanks for checking it out. I have found that the neutral negative ENSO phase has had the most major ZR's at ATL (and at least nearby CAD regions) by a large margin interestingly enough. Last Feb. was another example of an ATL major ZR in neutral negative. Weak Nino's/neutral positive have had some. Moderate to strong ENSO have had few. -PDO's seem to be a bit favored over +PDO 's for this by the way.

[franklin NCwx]

Who really cares what it is or isn't. We aint getting no snow with a trough in the west and a ridge in the east.

I do, one is transient the other is not.

[Cold Rain]

I do, one is transient the other is not.

Yeah, I hear ya. But for whatever reason it keeps wanting to reappear on the models in the LR. I know that's probably overdone, but so far, we've been in a non-transient bad pattern. I'm glad we're going to get some cold in Canada. I really do think things turn around mid-month.

[LithiaWx]

As we close the books on 2014 and stumble headlong into the new year, January looks to start off with a bang! The LR pattern is looking good and snow prospects should pick up as we head through the month.

So first off, I'd like to offer up Exhibit A, the 240 0z Euro. As you can see, Canada is nice and cold and the US is precariously positioned underneath the motherload, ready to be dumped on at any time (as you can clearly see by the tell-tale coast to coast frowny face pattern:

Euro240a.jpg

Next up, I'd like to submit into evidence Exhibit B, the 372 hr 0z GFS. Cold has dumped into the western US underneath the favorable smiley face pattern across the north. However, the cold has been forestalled indefinitely by the non-SE ridge-like-type feature not existing over and off of the SE coast:

GFSf372.gif

Next, take a look at Exhibit C, the 0z Navgem at 120. You can clearly see Canada quite cool with cold again dumping into the western US. The non-SE ridge-like-type non-feature is blocking the cold from spilling east, as evidenced by the gun-to-head pattern that has set up shop over northern Canada:

Navgem120.gif

The last operational model run to be submitted into evidence is Exhibit D, the 108 hr Canadian eh. You can clearly see the high pressure ridge extending off the NE coast, a hallmark of the bird poop pattern over central Canada extending down into the US:

CMCf108.gif

Exhibit E features a collage of indexes. The mountainous AO overlays an optimistic NAO and Atlantis-type PNA configuration:

ao_sprd2.gif

Continuing, we clearly see in Exhibit F the beloved High Five MJO forecast pattern, which is not important at all to the overall evolution of the pattern. I don't even know why I'm including it:

ECMF_phase_51m_small.gif

For our next to last piece of evidence, I'd like to submit Exhibit G, the equatorial Pacific SST chart, showcasing the popular pee-stain pattern, with some wind anomalies for good measure:

sstweek_c.jpg

Finally, for Exhibit H, here is the latest CFS for January. It clearly shows the middle finger pattern that is loved by virtually all east coast snow geese:

New Bitmap Image.jpg

Happy New Year!!

 

holy cow, nearly spit my coffee out a some of that stuff....  Price is right yodeler was the clincher. 

[franklin NCwx]

Yeah, I hear ya. But for whatever reason it keeps wanting to reappear on the models in the LR. I know that's probably overdone, but so far, we've been in a non-transient bad pattern. I'm glad we're going to get some cold in Canada. I really do think things turn around mid-month.

yeah it has sucked so far and it sucks more that are pna is transient. But hopefully the ensembles are right with the Aleutian Low and trough east of Hawaii. Hopefully that can lock in and we get a split flow instead of the pattern being transient.

[Webberweather53]

Interesting double top at +3 for the AO being modeled. If this was a stock this would be a good sign for a AO about take a steep dive.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif

 

 

Around the 5th/6th the OP has gone from negative to neutral several times for the last 10 runs...I'm kinda interested in this because a good amount of the members (roughly 14/21) dip at least neutral to negative during this time...however it does appear transient and the next chance to develop one would be around the 13th so mid-month as you can see with the lastest ensemble members. But we don't necessarily need an -AO for snow that's why the period before the 10th interests me.

 

Yeah, time around the 10th or so has been on the radar for a while...the GFS sucks. What I'm paying attention to is the Euro in the LR, which is the bottom tweet by Allan. Just comparing the Euro vs the GFS at 216 I believe it was shows how crappy the GFS is in the LR and why any "trend" whether positive or negative, in this case, should be ignored.

 

This isn't a surprise to me to see the AO/NAO spike like this despite guidance which attempted to hold it closer to neutral... You have to anticipate this was going to happen in relatively short order, especially when we saw a regeneration of the MJO over the Indian Ocean following CCKW passage last week, such a signal in tropical forcing usually precedes rising & +NAO regimes within ~ 10 days thru connections via Rossby Wave Trains & High-Frequency transients) as I've noted throughout a multitude of scientific literature & my own experience...

 

 

 

 

 

 

 

http://www.cerfacs.fr/globc/links/presentation/Sieste_cassou_2008.pdf

 

http://www.atmos.albany.edu/facstaff/roundy/convection/Walich14.pdf

 

A few important quotes from this paper, the latter of which I touched base on several days ago on this forum...

http://journals.ametsoc.org/doi/pdf/10.1175/2008JCLI2515.1

 

"On the other hand, when the MJO leads the NAO, significant positive NAOs are found for phases 2–4, and negative NAOs for phases 6–8, indicating a significant influence of the tropical MJO on the extratropical NAO variability. On average, the NAO index is positive (negative) 5–15 days after the MJO is detected in phases 2–4 (phases 6–8)"

 

"Several studies have suggested a possible wintertime connection between the MJO and the extratropical AO (e.g., Zhou and Miller 2005; L’Heureux and Higgins 2008). It was demonstrated that when the MJO-related convection is enhanced (depressed) over the Indian Ocean, the AO tends to favor its positive (negative)

polarity. In these studies, the phase of the AO was determined largely by its North Pacific center, which seems to have a more direct link with the tropical convection anomaly of the MJO"

 

"An analysis of the evolution of the 500-hPa geopotential height anomaly indicates that the NAO is linked to the equatorial middle Pacific convection anomaly of the MJO through a Rossby wave train"

 

 

You can even see the effects for yourself when looking @ 500mb MJO composites... 

 

December & January Phase 3 w/ amplitude

December & January Phase 4 w/ amplitude

December & January Phase 5 w/ amplitude

Even w/ the MJO projecting as a moist CCKW w/ weak amplitude over the Maritime Continent, it obviously still has major implications on the pattern

[Iceagewhereartthou]

The last 10 to 15 days of January seem to be special for us around these parts. A lot of good snows during that time period. I also like this part of the case study.

 

.The storm was not well forecast by numerical weather prediction models...[/size]...Following the event, research at NC State indicated that the inability of the operational models to resolve antecedent precipitation across the Deep South was a major reason for their forecast failure of the developing cyclone...[/size]...This event reinforces the need for forecasters to maintain situational awareness of upstream conditions and to compare model forecasts with observations...[/size]

I'm sure most would love a redo of that storm but it was a total utter skip job here in the western upstate, just some flurries. Sadly this has been the pattern since this storm. Feb 04, and last year's storm are two more big examples. Man we are due...

[deltadog03]

New post about today, and some current stuff, plus a question or 2.  Let me know what yall think.  Video will be done later with model talk.  I still think we are right on track, and I am going to show a map that I think will really help us.  -Chris 

 

https://www.facebook.com/ChriswxmanSimmons

[burgertime]

12z GFS not looking bad next week. More of a +PNA look vs. the 00z. 

[Webberweather53]

Webber,

Thanks for checking it out. I have found that the neutral negative ENSO phase has had the most major ZR's at ATL (and at least nearby CAD regions) by a large margin interestingly enough. Last Feb. was another example of an ATL major ZR in neutral negative. Weak Nino's/neutral positive have had some. Moderate to strong ENSO have had few. -PDO's seem to be a bit favored over +PDO 's for this by the way.

 

 

Interesting... I suspect the  -PDO/Neutral-Cold ENSO is more favorable for ice in Atlanta because this naturally favors a stronger SE US ridge & thus intensification of a warm layer aloft that's necessary for ice via advection of warm southwesterly flow on the western periphery of the ridge, (given other conditions are approximately equal of course) & forces the storm track further to the north & west, as opposed to suppression in +PDO & El Nino regimes...

 

500mb height anomaly difference top 10 strongest combined +DJF PDO/+OND ONI & -DJF PDO/ -OND ONI

[burgertime]

GFS PARA looks pretty freaking sweet out past hour 180. Big PV dropping down.

[FallsLake]

12z GFS would have a clipper provide precip (snow) from the NC/VA boarder northward at day 7/8. Something to keep an eye on, clippers have been able to produce in the past.

[burgertime]

GFS PARA brings the motherload down on the SE around hour 200...WOW. 

[burgertime]

This is what we want boys and girls if you like cold.