And we begin

[weathafella]

Siberia continues to ramp up.

[The_Global_Warmer]

Eastern Siberia is progged to get pretty warm.

I have no idea how vulnerable the snow is at this point.

This Surface OBS graph which is time sensitive shows temps mostly below zero over the snow cover regions in Siberia but a large ridge of HP is building in with quite warm 850MB temps with widespred 6-15C 850mb temp anomaly's over the Eastern quarter of Siberia, I am not familiar with snow melt or gains under these conditions. I would assume snow is pretty wet in different places, a nice icy layer should form because above freezing temps should be harder to come by.

Does anyone have access to snow depth charts for Siberia?

I can see why the goal is to lower albedo around 60-65N in October. While it quickly goes down throughout the month. Solar energy is still decent. The faster snow cover get's a hold, it will have more and more manipulation of weather patterns.

Even on the midst of warming climate above normal snow cover from mid to late October-March can give the NH very cold winters.

Probably with more wild storms cause oceans are so warm. Fun times ahead.

[das]

Eastern Siberia is progged to get pretty warm.

I have no idea how vulnerable the snow is at this point.

Does anyone have access to snow depth charts for Siberia?

Here is the multisensor (METOP AVHRR, MSG SEVIRI, GOES Imager and DMSP SSMIS) snowcover map overlaid with observed (not remote-sensed) ground observations. It's updated daily and, obviously, obs points are sparse. Zoom in and look for the little red triangles. If your browser can't zoom in, here's a direct link:

http://www.star.nesdis.noaa.gov/smcd/emb/snow/images/multisensor/eurasia/recent/multisensor_4km_ea_snow_ice_map_fulres_recent.png

[GaWx]

The 12Z Wed. GFS snow fall maps suggest that Siberia will fill in quite well over the next two weeks. If this run is of decent accuracy, these areas should get good snowfall in most areas: SE Siberia down to the NE China border, Central Siberia all the way down to far northern Mongolia, and SW Siberia down into much of Kazakhstan. In summary, much of southern Siberia should get good snowfall between now and 10/24. I don't know that that would get snowcover ahead of climo since by 10/24 nearly all of Siberia and much of Mongolia are normally covered. However, it should at least be pretty close to keeping up with climo.

[GaWx]

I wasn't sure of the best thread for this, but I'll put it here. Per the NOAA PDO table, the PDO fell even further from -2.32 in Aug. to -2.82 in Sep.:

ftp://ftp.ncdc.noaa.gov/pub/data/cmb/ersst/v3b/pdo/pdo.dat

This is surprising to me as I had expected the PDO to rise from the low Aug. level. The other PDO table, which I had been following recently, has yet to update for Sep.:

http://jisao.washing.../pdo/PDO.latest

The JISAO negatives have tended to be lower in magnitude than NOAA's. Regardless, the NOAA -2.82 suggests the chance for a sub -2 in JISAO in Sep. I had been expecting a rise in JISAO from the -1.93 of Aug. to something above -1.50 in Sep. due to SST anom. changes since mid-Sep.

Here's an animation of the last two weeks of SST anom.'s using 1971-2000 as the base period:

http://www.esrl.noaa....anim.week.html

It still looks like to me that the classic -PDO structure is collapsing...even more now as we've had a solid -EPO for the last week.

1) Key area #1 for PDO calc.: It appears to my eyeballs that key area #1 (bounded by 150W, 150E, 30N, and 50N) is getting very close to neutral as of 10/9. I'll dissect it further to better illustrate my point:

a. section bounded by 150W, 180, 30N, and 50N: I estimate that 75% of this is blue (cool)

b. section bounded by 150E, 180, 30N, and 50N: I estimate that 33% of this is blue (cool) or white (normal)

So, when combining sections a and b, I roughly estimate per my eyeballs that key area #1 is averaging pretty close to normal. In order for the PDO to calc. as solidly negative, that area would normally average warm as opposed to near normal.

2) Key Area #2 for PDO calc.: from Gulf of Alaska through the area within a few hundred miles of the west coast of North America down to ~Baja. I'd say the GOA is averaging only slightly cool. The area offshore W. Canada is averaging slightly warm imo. The area off of the U.S. is averaging a bit cool. Finally, the area off of Baja is warm. So, per my eyeballs, I'd say that the entire key area #2 is averaging only very slightly cool...say ~-0.25 to -0.50 C. In order for the PDO to calc. as solidly negative, key area #2 would normally average solidly cool as opposed to just very slightly cool as it appears to be now.

3) PDO = key area #2's average anom. minus key area #1's avg. anom. So, we have ~-0.25 to -0.50 minus ~0...this should give us only a slightly negative PDO as of 10/9 of ~-0.25 to -0.50 per my eyeballs as opposed to the strongly negative PDO of August into early Sep. If this SST pattern were to more or less stick around through the end of Oct., I'd expect an Oct. PDO to be well above

-1.00...maybe near -0.50. If the momentum of a rising PDO were to continue through 10/31, I'd say that a near 0 PDO wouldn't at all be out of the question.

Jerry/anyone else, any opinions/comments?

[SVT450R]

[das]

Since the research is largely focused on Eurasian snowcover in October, here's a zoomed multisensor output map of the area starting 01 October 2012. You can see some of the ridge-induced melt in NE and N-central Siberia icebreaker talked about last week in the last couple of frames.

[SVT450R]

[Alpha5]

Very nice gains, looking much better over central russia than last year when the snow was cramped into the eastern parts of siberia

[weathafella]

Doing better vs last year. We probably need to look at this more carefully in a week but in retrospect, there were some early signs of a winter that would not get going a year ago.

[Eskimo Joe]

Doing better vs last year. We probably need to look at this more carefully in a week but in retrospect, there were some early signs of a winter that would not get going a year ago.

Compared to last year, I agree. The animated .gif below shows Northern Hemisphere snow cover from Week 37 -> Week 39 from the Rutgers University Global Snow Lab. The first image, Week 37, shows 3.54 million sq. km of snow cover in North America, and 0.80 million sq. km of snow cover in Eurasia. The third image, Week 39, shows a noticeable increase in North American snow coverage to 4.04 million sq. km, and a noteworthy increase in Eurasian snow cover to 2.69 sq. km.

[cfbaggett]

Here's snowfall extent in Eurasia, as defined by Judah Cohen's paper (0 to 180E, 25N to 60N). Red is 2009 (followed by -AO), blue is 2007(followed by +AO), and green is this year.

The rate of advance, half way through the month looks very healthy... I'm hoping for a big second half to the month. If the GFS ensembles are correct, western Russa/Europe will be cold and stormy soon which should allow snow cover to expand rapidly.

[tacoman25]

According to a post in the climate change forum, the NH snowcover is now above normal.

[BlizzardWx]

It looks like both sea ice and snowcover have really exploded over the last week. Certainly nice to see. I remember that there is a correlation between Siberian snowcover and the winter ahead, can anybody briefly refresh me on what that was again.

[wxmx]

It looks like both sea ice and snowcover have really exploded over the last week. Certainly nice to see. I remember that there is a correlation between Siberian snowcover and the winter ahead, can anybody briefly refresh me on what that was again.

http://www.americanwx.com/bb/index.php/topic/36669-and-we-begin/#entry1749940

[BlizzardWx]

http://www.americanw...n/#entry1749940

Thanks, I think I got it now!

I know this mostly talks about the eastern US but I can't help but assume that here in the mountain west I would want a -AO over a positive right? I know of some instances where we have gotten very cold here even with a raging positive AO but from the sounds of it all midlatitudes should have some benefit to a weaker polar vortex.

[okie333]

00Z GFS

[icebreaker5221]

Here's snowfall extent in Eurasia, as defined by Judah Cohen's paper (0 to 180E, 25N to 60N). Red is 2009 (followed by -AO), blue is 2007(followed by +AO), and green is this year.

The rate of advance, half way through the month looks very healthy... I'm hoping for a big second half to the month. If the GFS ensembles are correct, western Russa/Europe will be cold and stormy soon which should allow snow cover to expand rapidly.

Keep updating this graph throughout the month! That's a very useful way to visualize the information.

[Mallow]

Keep updating this graph throughout the month! That's a very useful way to visualize the information.

Agreed, keep us updated!

[cfbaggett]

We are looking really good the first 18 days of the month. Nearly all the snow is in eastern Russa right now. The cold, according to the ensembles, is shifting west toward Moscow/Europe. I expect the advance to continue, 6.5 to 7.5 million km^2 total extent by the end of the month should be doable. We are looking to tie or perhaps beat 2009, but with an overall greater average extent. Or so I hope!

[SVT450R]

[Eskimo Joe]

Looks like a noteworthy positive anomaly in lower Siberia. It should be interesting to see what the Week 38 -> Week 40 snow gains are when the updated data is made available next Monday.

[NJwinter23]

We are looking really good the first 18 days of the month. Nearly all the snow is in eastern Russa right now. The cold, according to the ensembles, is shifting west toward Moscow/Europe. I expect the advance to continue, 6.5 to 7.5 million km^2 total extent by the end of the month should be doable. We are looking to tie or perhaps beat 2009, but with an overall greater average extent. Or so I hope!

Hey, great graph and analysis! Obviously a lot can happen in the final 10 days, and above average now doesnt guarantee anything by month's end since the rate of average advancement increases more exponentially..but I agree the pattern looks very favorable with western Asia getting into the game on the model data...

would you happen to know, numbers wise, how this year stacks up to 2002 thus far?

[Rainshadow]

Hey, great graph and analysis! Obviously a lot can happen in the final 10 days, and above average now doesnt guarantee anything by month's end since the rate of average advancement increases more exponentially..but I agree the pattern looks very favorable with western Asia getting into the game on the model data...

would you happen to know, numbers wise, how this year stacks up to 2002 thus far?

2002 I think was the second ranked snow cover October, kind of in a league of its own.

At anyrate as of "today" goes:

2002

2012

[Mallow]

2002 I think was the second ranked snow cover October, kind of in a league of its own.

At anyrate as of "today" goes:

2002

2012

South of 60N, it looks like 2002 wasn't actually that much snowier than 2012 at this time.

[NJwinter23]

2002 I think was the second ranked snow cover October, kind of in a league of its own.

At anyrate as of "today" goes:

2002

2012

Thanks Tony!

South of 60N, it looks like 2002 wasn't actually that much snowier than 2012 at this time.

That was my take on things as well Mallow...and it would appear we can make up that westward extent some in the next 10 days with the projected pattern on the euro ensembles.

[phlwx]

We are looking really good the first 18 days of the month. Nearly all the snow is in eastern Russa right now. The cold, according to the ensembles, is shifting west toward Moscow/Europe. I expect the advance to continue, 6.5 to 7.5 million km^2 total extent by the end of the month should be doable. We are looking to tie or perhaps beat 2009, but with an overall greater average extent. Or so I hope!

Can you include '06 in the data set, if possible?

Thanks

[cfbaggett]

Can you include '06 in the data set, if possible?

Thanks

October 2006 had a snow advance of 161,000 km^2 per day, a little below normal.

[cfbaggett]

Snow cover retreated the past couple of days. However, the GFS shows a nice rebound plus some over the next few days... with extent spreading westward and a storm darting north of North Korea. My hope is that we are sitting on 6 to 7 million km^2 by the 25th or 26th which seems entirely doable based on the GFS. We'll see.

[das]

Snow cover retreated the past couple of days. However, the GFS shows a nice rebound plus some over the next few days... with extent spreading westward and a storm darting north of North Korea. My hope is that we are sitting on 6 to 7 million km^2 by the 25th or 26th which seems entirely doable based on the GFS. We'll see.

Great chart, btw.

Here's the animation for the month through yesterday.

Snow depth is also increasing, guarding against an occasional warm up. Here's a link to the depth chart:

http://www.star.nesdis.noaa.gov/smcd/emb/snow/images/multisensor/eurasia/recent/multisensor_4km_ea_snow_ice_map_fulres_recent.png