Winter 2014-2015 Thread

[Deck Pic]

Dec 0- +1

Jan -1 - -2

Feb -1 - -2

Snow DCA 12-15

 

hmmmm

[yoda]

CWG comes out either later this week or next week..I wonder how they will go....

 

Also depends on the rating of the winter... like will it be a 7/10 winter?

[BTRWx]

I just saw this on my Twitter feed. How will the above normal Siberian snow cover be impacted? https://pbs.twimg.com/media/B1hWjJUCcAAfxL3.png

[WxUSAF]

I just saw this on my Twitter feed. How will the above normal Siberian snow cover be impacted? https://pbs.twimg.com/media/B1hWjJUCcAAfxL3.png

 

Potentially, this is the RESULT of the snowcover.  This is the mechanism that Cohen and Co. have postulated, that above normal snowcover leads to wave activity that propagates into the stratosphere and disrupts the vortex, leading to a -AO.  And lo and behold, it looks like we're going to have a solidly -AO for much of the first 2 weeks of November at least.  This warming indicated on the Euro would suggest it continues.  

[mitchnick]

Potentially, this is the RESULT of the snowcover.  This is the mechanism that Cohen and Co. have postulated, that above normal snowcover leads to wave activity that propagates into the stratosphere and disrupts the vortex, leading to a -AO.  And lo and behold, it looks like we're going to have a solidly -AO for much of the first 2 weeks of November at least.  This warming indicated on the Euro would suggest it continues.  

not so sure it could get any better from our perspective either considering it's close to the top of the scale

[BTRWx]

not so sure it could get any better from our perspective either considering it's close to the top of the scale

For some reason I thought I was sharing a 500mb chart. That wouldn't be so pretty; Glad to see the signs heading in our favor.

[usedtobe]

Agreed. Nov snow isn't something to wager anything on around here. 95-96 & 96-97 we're the last 2 measurable at IAD. But not too far back in the 70's and 80's there were enough occurrences to keep the disco open to a chance.

March last year was an obvious statistical anomaly but it wasn't just one fluke. It was a solid snow pattern for a few weeks. Ensembles are advertising a pattern after next weekend that could produce snow in Nov. Obviously if any threat appears the further n-w the better chance.

 

Tryting to decide whther to hold off on my two week outlooks until after vets day or to write one in the next week or so.  Pattern does look cold and I'm increasingly optimistic about below normal temps for the winter. 

[WinterWxLuvr]

Potentially, this is the RESULT of the snowcover.  This is the mechanism that Cohen and Co. have postulated, that above normal snowcover leads to wave activity that propagates into the stratosphere and disrupts the vortex, leading to a -AO.  And lo and behold, it looks like we're going to have a solidly -AO for much of the first 2 weeks of November at least.  This warming indicated on the Euro would suggest it continues.  

Good answer....thanks for posting.

 

It also is worth noting that that is a 360 hour forecast which is unlikely to be correct, Euro ensembles or not.

[WinterWxLuvr]

Tryting to decide whther to hold off on my two week outlooks until after vets day or to write one in the next week or so.  Pattern does look cold and I'm increasingly optimistic about below normal temps for the winter. 

OMG, you just sent a bunch of people over the edge.

[Bob Chill]

Tryting to decide whther to hold off on my two week outlooks until after vets day or to write one in the next week or so.  Pattern does look cold and I'm increasingly optimistic about below normal temps for the winter. 

 

The d10-15 h5 mean is really something to behold. Quite similar with anomaly placements to Nov 02 in our hemisphere. 02 and 76 are popping up a lot in CPC d8 & 11+

 

Here's what  the second half of Nov looked like in 02

 

 

Last 2-3 euro ens runs look like this with 5 day mean:

 

 

 

Another interesting comparison is the Oct AO behavior compared to Oct this year:

 

 

 

 

 

02-03 was one of the few -ao winters that had consistent blocking starting at the beginning of Nov and lasting almost a full 3 months until late Jan. 

 

 

 

76-77 and 09-10 didn't really latch on to a lasting -ao pattern until Dec. 

 

It will be interesting as we move forward if the current -AO forecast to strong neg is the beginning of a lasting pattern into the winter months or will there be a relaxation in Dec before re-establishing. 

 

Most strong -ao's in winter last at least 45-60 days but I'm not sure about typical periods when they begin in Nov. I'll dig around a little. 

[WxUSAF]

Good answer....thanks for posting.

 

It also is worth noting that that is a 360 hour forecast which is unlikely to be correct, Euro ensembles or not.

It is a 360hr forecast, but 2 facts make far more than a 360hr GFS forecast:

1.  It's the Euro ensembles

2.  The stratosphere is far more predictable at long leads than the troposphere.  

[Bob Chill]

It is a 360hr forecast, but 2 facts make far more than a 360hr GFS forecast:

1.  It's the Euro ensembles

2.  The stratosphere is far more predictable at long leads than the troposphere.  

 

It's a strong signal and begins well in advance of d15. Another thing that gives it some cred is it's the expected result of a high SAI October. 06 was an obvious disaster irt the AO response but it was also the opposite of that 50mb plot in Nov. ORH and Coastal have made some really nice posts about it in the SNE forum. 

[Bob Chill]

Nino is trying hard but a seriously late bloomer. I still think getting an official nino is only for posterity at this point but would still be an accomplishment nonetheless after constantly chasing a ghost this year. 

 

[aldie 22]

OMG, you just sent a bunch of people over the edge.

Issue is weak ninos aren't big snow producers here...so we may be looking at Mattie's worst nightmare...cold and dry

[WxUSAF]

Issue is weak ninos aren't big snow producers here...so we may be looking at Mattie's worst nightmare...cold and dry

Given that weak ninas/cold neutrals and mod ninos are typically the best for us, it's curious that weak ninos/warm neutrals haven't been big snow producers.  I wonder if this is all just small sample size issues and with a suitably large sample (and a climate that isn't shifting), we'd see a more normal distribution around some "ideal ENSO" state.  

 

It makes meteorological sense (to me at least) why mod ninos are our biggest years and why strong ninos and strong ninas are typically worse.  I'd think that that warm neutrals/weak ninos SHOULD be better than they have been, on average.  

[aldie 22]

Given that weak ninas/cold neutrals and mod ninos are typically the best for us, it's curious that weak ninos/warm neutrals haven't been big snow producers.  I wonder if this is all just small sample size issues and with a suitably large sample (and a climate that isn't shifting), we'd see a more normal distribution around some "ideal ENSO" state.  

 

It makes meteorological sense (to me at least) why mod ninos are our biggest years and why strong ninos and strong ninas are typically worse.  I'd think that that warm neutrals/weak ninos SHOULD be better than they have been, on average.

Seems like we are hitting the indices jackpot this year as modeled...wonder if that ever has happened with a week niño and how that changes things if at all. NAO gonna be most crucial in my opinion this year...gotta get any storm to turn the corner...or there will be a lot of congrats South Carolina

[WinterWxLuvr]

It is a 360hr forecast, but 2 facts make far more than a 360hr GFS forecast:

1.  It's the Euro ensembles

2.  The stratosphere is far more predictable at long leads than the troposphere.  

Did not know that.  Thanks for the info.

[mitchnick]

Nino is trying hard but a seriously late bloomer. I still think getting an official nino is only for posterity at this point but would still be an accomplishment nonetheless after constantly chasing a ghost this year. 

 

another tick warmer this week where it counts

                Nino1+2      Nino3        Nino34        Nino4 Week          SST SSTA     SST SSTA     SST SSTA     SST SSTA

 15OCT2014     21.5 0.7     25.5 0.5     27.2 0.5     29.4 0.7 22OCT2014     21.8 0.8     25.8 0.8     27.2 0.5     29.4 0.7 29OCT2014     21.8 0.6     25.8 0.9     27.3 0.6     29.4 0.8

[GaWx]

It's a strong signal and begins well in advance of d15. Another thing that gives it some cred is it's the expected result of a high SAI October. 06 was an obvious disaster irt the AO response but it was also the opposite of that 50mb plot in Nov. ORH and Coastal have made some really nice posts about it in the SNE forum. 

 

 Bob,

 I guess you don't realize that the 2006 SAI was actually positive despite the rather generous SCE. So, the SAI, itself a better predictor than the SCE for the DJF AO, actually made an excellent DJF 06-07 AO prediction.

 

 SAI:   http://onlinelibrary.wiley.com/doi/10.1029/2011GL049626/full

 

 I used to get confused about what is a better predictor for the AO, but I think I have it straight now.

 

Edit: correction. I should have said that the 2006 SAI was actually negative, not positive, as it is negatively correlated with the AO. Otherwise, the rest of the post is what I meant to say.

[BTRWx]

Nino is trying hard but a seriously late bloomer. I still think getting an official nino is only for posterity at this point but would still be an accomplishment nonetheless after constantly chasing a ghost this year. 

 

Have there been any late season Nino analog years? For anyone interested, NASA has a nice historical database for sst and surface temperature charts. http://data.giss.nasa.gov/gistemp/maps/

[mitchnick]

idk about precip, but the 12z run of the Euro sure is cold

[wildweatherman179]

Have there been any late season Nino analog years?

I'm not from the mid atlantic but I read the posts here a lot. The best fit year as an analog I found based solely on Niño was 1976-77. It started in the ASO tri-monthly. 1977-78 was pretty close to it as well.

[BTRWx]

I'm not from the mid atlantic but I read the posts here a lot. The best fit year as an analog I found based solely on Niño was 1976-77. It started in the ASO tri-monthly. 1977-78 was pretty close to it as well.

Thanks!

[eurojosh]

I'm not from the mid atlantic but I read the posts here a lot. The best fit year as an analog I found based solely on Niño was 1976-77. It started in the ASO tri-monthly. 1977-78 was pretty close to it as well.

 

Is there such a thing as a "quick-look analogs" page anywhere online?  It would be a year-by-year database of atmospheric conditions (Nino/Nina, ENSO, AO, NAO, etc), and US regional monthly temp and precip variation.  So that when someone lists a less familiar year, you can go right to the page and say "ah, I see why that's being said and where it could lead"...

[wildweatherman179]

Thanks!

No problem! I enjoy reading what you all have to say!

[BTRWx]

I'm not from the mid atlantic but I read the posts here a lot. The best fit year as an analog I found based solely on Niño was 1976-77. It started in the ASO tri-monthly. 1977-78 was pretty close to it as well.

Fwiw, I think a big difference those years was in the Gulf of Alaska.

[Bob Chill]

 Bob,

 I guess you don't realize that the 2006 SAI was actually positive despite the rather generous SCE. So, the SAI, itself a better predictor than the SCE for the DJF AO, actually made an excellent DJF 06-07 AO prediction.

 

 SAI:   http://onlinelibrary.wiley.com/doi/10.1029/2011GL049626/full

 

 I used to get confused about what is a better predictor for the AO, but I think I have it straight now.

 

Edit: correction. I should have said that the 2006 SAI was actually negative, not positive, as it is negatively correlated with the AO. Otherwise, the rest of the post is what I meant to say.

 

I thought it was a bust year for some reason. It was a big gainer for all of eurasia based on Rutgers but I didn't dig deeper into the below 60N stuff. 

 

[wildweatherman179]

Is there such a thing as a "quick-look analogs" page anywhere online? It would be a year-by-year database of atmospheric conditions (Nino/Nina, ENSO, AO, NAO, etc), and US regional monthly temp and precip variation. So that when someone lists a less familiar year, you can go right to the page and say "ah, I see why that's being said and where it could lead"...

That's why I included the 'based solely on Niño' phrase. I'm pretty sure that is the year I have seen used the most as an analog to date. I don't know of a database like that but it would be awesome.

[wildweatherman179]

Fwiw, I think a big difference those years was in the Gulf of Alaska.

You're probably right.

[TeleConnectSnow]

The end of the 12z EURO is cold cold cold. Looking at the 2M Temps, its something to see this early on this season compared to the original thoughts of a mild nov.