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The -QBO during winter has been shown in papers to be correlated with a -AO winter. And the weak/moderate EL Nino/+PDO/-QBO combo is usually a good one for widespread blocking and a -AO.

 

If you isolate winters with an average DJF MEI value of 0.4 to 1.26, basically bordeline weak El Nino to low/mid range moderate El Nino events (likely this year), every year that had an average DJF QBO with a negative phase had an average DJF AO in the negative range. Every year!

1965-66

1958-59

2009-10

1976-77

1979-80

1986-87

1968-69

2002-03

 

The average value of the AO in those 8 years was -1.54. Ranging from -0.39 in 58-59 to -3.422 in 09-10. In all those years except 1 (79-80) the NAO also average negative 79-80 average +0.1.

 

In those 8 winters, 5/8 Decembers had a -AO, 8/8 Januarys, 6/8 Februarys.

 

Also of note we dont have Rutgers data before 1966, but three of the 6 winters in that list ranked in the top 10 for week 42 snow cover, 2009, 2002, 1976. Which finisehd with DJF AO's of -3.4, -0.65, -2.6

 

The EN/PDO/QBO combo had me already thinking a -AO is favored for this winter, the fact that the October snow data is so impressive only leads me to think that this is even more favored and that the odds favor more of a moderate to strong -AO then a weak -AO.

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Agree.

If you want to get a good idea on the daily "health" of the snowpack where it really matters, there are ways to check. Here's the larger VIIRS snow temp map of Eurasia. Sorry for the large file size. Again, from 2am last night. As well, here's the folder to get them from in the future: ftp://www.star.nesdis.noaa.gov/pub/smcd/emb/snow/viirs/snow-fraction/images/north-east/

Screen Shot 2014-10-29 at 6.23.29 AM.png

Thanks. Impressive product

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Ok...I just looked it up.. the QBO looks good, the AO, NAO, and PNA all look to be near neutral around mid- November, the ENSO is trying to stay around +.5, and the PDO is at +1.08 (as of Sept. and has been positive all year long)....the SC and SAI in Eurasia this year is near record levels... the only piece missing is the stratosphere.....if that cooperates, who knows how much snow we could get....

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Added the 28th to the loop: http://www.daculaweather.com/4_sample_loop2.php

 

Interesting. The loop actually shows decent gains (reds) in parts of SW Russia between 50N and 60N on the 10/28 map vs. 10/27. Also, the western flank looks pretty stout to me on this and much better than the latest Rutgers/Natice map there. Per what das has been saying, I assume it is due to resolution differences. Even though it matters little this late, I suppose it can't hurt to have new SC in areas below 60N. I'm a bit surprised it just showed up there considering the current weather but will assume it is real (or some kind of correction) and take it.

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Interesting. The loop actually shows decent gains (reds) in parts of SW Russia between 50N and 60N on the 10/28 map vs. 10/27. Also, the western flank looks pretty stout to me on this and much better than the latest Rutgers/Natice map there. Per what das has been saying, I assume it is due to resolution differences. Even though it matters little this late, I suppose it can't hurt to have new SC in areas below 60N. I'm a bit surprised it just showed up there considering the current weather but will take it.

 

Still matters a little.  While I look more closely at the correlation with U.S. temperatures, if you just want your teleconnection correlation... the Eurasian snow to winter AO correlation peaks on October 29th (that's after doing the week adjustments and linear interpolations to get daily values... imperfect, but in bulk stats, trying to get correlations like this, is probably fine).  I'm "done"... satisfied... this year came in #2 on the list (behind only 1976) on the peak date for correlation to U.S. temps.  But if you're tracking for AO purposes, we're not done yet... close... but not quite.

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Still matters a little. While I look more closely at the correlation with U.S. temperatures, if you just want your teleconnection correlation... the Eurasian snow to winter AO correlation peaks on October 29th (that's after doing the week adjustments and linear interpolations to get daily values... imperfect, but in bulk stats, trying to get correlations like this, is probably fine). I'm "done"... satisfied... this year came in #2 on the list (behind only 1976) on the peak date for correlation to U.S. temps. But if you're tracking for AO purposes, we're not done yet... close... but not quite.

Millwx,

Thank you for your guidance. I'm more interested in the AO. I assume the temperature factor is actually based on a population weighted HDD average (as used by the heating energy industry) based on what you've said. If it is weighted that way, then the NE and Midwest would get quite a bit more weight than the SE US. Being that I'm in the SE, I'd prefer to concentrate on the AO and look at how the AO typically affects this region. Therefore, the AO is more useful to me for winter forecasting discussion purposes.

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http://www.natice.noaa.gov/ims/files/Helfrichetal_HP07.pdf

The Interactive Multi-sensor Snow and Ice Mapping System (IMS) are the Snow and Ice Maps that are posted from NATICE. The IMS is housed at the National/Naval Ice Center (NIC) in Suitland, MD.

The IMS is a daily Northern Hemisphere Ice and Snow analysis produced by analysts and is due at 5:00 p.m. ET. This is the second version of the IMS System. It is currently run at 4 km resolution and upscaled to 24 km for to maintain the historical dataset. The 4 km version of the product is currently ingested into the ECMWF and the 24 km version into models such as the GFS, NAM, etc. When the IMS is upgraded to version 3 the resolution will increase to 1 km.

On the current version of the IMS the analyst plots snow and ice cover using a variety of different sources. Of course your Geostationary satellites, Polar Orbiting Satellites, Autosnow (your Multi-sensor snow chart from above), National Ice Center MIZ Lines, Surface Observations, SNOWTEL, Webcams, Global Numerical Forecasting Models, and much more. A short term forecast to 00z is incorporated into the analysis to account for any changes the analyst feels might occur between 5 pm ET and 00z.

IMS Version 3.0 is going to feature many more new features including the introduction of two new features (days since last observed and snow depth).

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Ok...I just looked it up.. the QBO looks good, the AO, NAO, and PNA all look to be near neutral around mid- November, the ENSO is trying to stay around +.5, and the PDO is at +1.08 (as of Sept. and has been positive all year long)....the SC and SAI in Eurasia this year is near record levels... the only piece missing is the stratosphere.....if that cooperates, who knows how much snow we could get....

*EDIT: I forgot to add the OPI, which is also looking favorable for us....

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This is not really the greatest year for analogs atleast using the 1950 or later ones. The fall pattern/precip etc is not following along with the so called favored ones and in recent years when i have seen this sort of thing you typically have to go back to pre 1950 to get decent analogs..

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I am not trying to be a dick. But could you please stop cluttering up what is one of the best threads in the history of this site? PLEASE read more and let the pro's do their thing.

 

This is a public forum is it not? I think that everyone should be able to share their thoughts and opinions on the matter if they want, regardless of their experience.

 

Anyway.. here's my most updated snow coverage % chart. Again, black line (2014) is from what is initialized with the GFS op.  The other years are from the ERA-Interim. I will be revisiting this chart later in the year once the ERA-Interim data is there for October 2014 so we can see how far off the GFS op initialization data was from reality.

 

Looks like a pretty decent decline of snow cover over the past couple of days.

 

Eurasia_SNOW%25_TS.png

 

 

Most of the reduced snow cover is coming from western Eurasia.

 

snowD.png

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Looks like some gains were made today.

Per cfbaggett's graph, the loss on 10/28 was the biggest single day loss of sub 60N this month, ~0.8 to 0.9 msk. That loss looks like it was the 2nd largest daily loss of any of the years on the chart next to a >1.0 loss on 10/30/13. However, despite it being large, cfbaggett and several others are saying it is too late for it to matter more than trivially (though I still would have preferred it not mess with the indices for record-keeping purposes). Also, for record-keeping purposes, it still will finish about on par with 2009 absent any more large losses on the last two days of this month, which would likely mean a top three along with 1976 and 2009. Praetorian is saying some net gains for 10/30?

Edit: I meant on par with 2009 with regard to SAI absent any large losses 10/30-1. It looks like my prediction of the max being ~10/27-8 area will verify since the max will almost definitely end up on 10/27.

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Per cfbaggett's graph, the loss on 10/28 was the biggest single day loss of sub 60N this month, ~0.8 to 0.9 msk. That loss looks like it was the 2nd largest daily loss of any of the years on the chart next to a >1.0 loss on 10/30/13. However, despite it being large, cfbaggett and several others are saying it is too late for it to matter more than trivially (though I still would have preferred it not mess with the indices for record-keeping purposes). Also, for record-keeping purposes, it still will finish about on par with 2009 absent any more large losses on the last two days of this month, which would likely mean a top three along with 1976 and 2009. Praetorian is saying some net gains for 10/30?

Edit: I meant on par with 2009 with regard to SAI absent any large losses 10/30-1. It looks like my prediction of the max being ~10/27-8 area will verify since the max will almost definitely end up on 10/27.

I'll plot the trend line with the slope value for 2014 in a couple of days. 2009 had a rate of 260,000 msk/day. We are going to be near 300,000 msk/day for 2014. The worst year, 2007, had 120,000 msk/day. So I would contend that 2014 is not exactly on par with 2009, but is beating 2009 rather handily. Plus SCE was so much greater throughout 2014 compared to 2009.

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I'll plot the trend line with the slope value for 2014 in a couple of days. 2009 had a rate of 260,000 msk/day. We are going to be near 300,000 msk/day for 2014. The worst year, 2007, had 120,000 msk/day. So I would contend that 2014 is not exactly on par with 2009, but is beating 2009 rather handily. Plus SCE was so much greater throughout 2014 compared to 2009.

Cfbaggett,

1) I was talking about comparing raw increases with 2009. 2014 started off ~0.8 higher than 2009 and is now ~0.8 higher than the 10/31 value for 2009. So, based on raw numbers, the net gain for 2014 would end up about the same as 2009 assuming 2014 ends near where it is now. However, I also realize you're using trend lines in your analyses as opposed to raw numbers, which smooths things out and makes sense. So, that would reduce the effect of the big 10/28 drop and keep 2014 ahead of 2009 on the trend line basis, which probably is more significant.

2) Yes, I realize the 2014 SCE will beat 2009. However, SAI has been a better predictor of winter -AO based on a higher correlation per analysis of actual AO values of past years vs SAI. Nevertheless, 2014 looks to finish ahead of 2009 even for SAI based on trend lines. So, we're looking good regardless.

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I'll plot the trend line with the slope value for 2014 in a couple of days. 2009 had a rate of 260,000 msk/day. We are going to be near 300,000 msk/day for 2014. The worst year, 2007, had 120,000 msk/day. So I would contend that 2014 is not exactly on par with 2009, but is beating 2009 rather handily. Plus SCE was so much greater throughout 2014 compared to 2009.

 

The fact that you were forced to extend the upper bounds in your plot was all we needed to see this Oct   :lol:

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Cfbaggett,

1) I was talking about comparing raw increases with 2009. 2014 started off ~0.8 higher than 2009 and is now ~0.8 higher than the 10/31 value for 2009. So, based on raw numbers, the net gain for 2014 would end up about the same as 2009 assuming 2014 ends near where it is now. However, I also realize you're using trend lines in your analyses as opposed to raw numbers, which smooths things out and makes sense. So, that would reduce the effect of the big 10/28 drop and keep 2014 ahead of 2009 on the trend line basis, which probably is more significant.

2) Yes, I realize the 2014 SCE will beat 2009. However, SAI has been a better predictor of winter -AO based on a higher correlation per analysis of actual AO values of past years vs SAI.

I don't disagree with anything you are saying... but we will end up with a higher slope (linear regression of all 31 days is the basis of the SAI) not because of values on 10/1 and 10/31 but rather because of the preponderence of days at the end of 2014 that are higher than 2009.

 

As a counterexample, SCE was really high last year but the SAI in the middle of the pack at best. The SAI did decently well predicting the AO, as you mention.  However, I would say the SCE had a very large impact on building cold air masses early last year which led to the record-breaking cold in the US.

 

Unlike last year, this year we have the best of both worlds in terms of SAI and SCE... and it makes me quite hopeful that this winter will rock.

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I don't disagree with anything you are saying... but we will end up with a higher slope (linear regression of all 31 days is the basis of the SAI) not because of values on 10/1 and 10/31 but rather because of the preponderence of days at the end of 2014 that are higher than 2009.

As a counterexample, SCE was really high last year but the SAI in the middle of the pack at best. The SAI did decently well predicting the AO, as you mention. However, I would say the SCE had a very large impact on building cold air masses early last year which led to the record-breaking cold in the US.

Unlike last year, this year we have the best of both worlds in terms of SAI and SCE... and it makes me quite hopeful that this winter will rock.

Cfbaggett,

Sounds great! These are fascinating discussions. We're pretty much in agreement. I also expect a quite cold winter in much of the E US due to a combo of expected strong -AO (based on high SAI and OPI), +PDO, and weak El Niño. It is hard to beat that combo if you want to see the best chance at a very cold E US winter looking back in history. Plus the cold air potential due to high SCE is also there as you said. I'm more excited about the high prospects for a solidly cold winter for 2014-5 than I have been for any other winter at least since I've been reading wx BB's. The problem with very cold winter predictions from someone like JB is that many think it is mainly hype due to his history of overhyping cold. I happen to think he's being realistic this time.

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Am I the only one concerned with that large patch of Above Average SSTA in the Arctic Ocean above the UK?

 

 

Concerned how?

 

Recent research has shown that a lack of sea-ice (and/or warm water temperatures) in the Barents and Kara Sea during late Fall is a harbinger for a -AO during the following winter. (Feldstein and Lee 2014; Cohen et al. 2014; Kim et al. 2014)

 

That warm SSTA is great news for winter weather lovers.

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