Jump to content

  • Member Statistics

    17,609
    Total Members
    7,904
    Most Online
    NH8550
    Newest Member
    NH8550
    Joined

And we begin

weathafella

Recommended Posts

uncle W

uncle W

Posted
Posted

You're right, 52-53 was only weakly negative. 1951 has been one of my primary analogs through this past summer and it looks like it may be a good one going forward. The august PDO value is more strongly negative than last month, which isn't good news:

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

This puts 12-13 closest to 51-52 PDO wise if we have a weak nino. I can see the PDO warming over the next few months, but usually by September we see some indication of reversal, and we've gone the wrong direction. Going to have to hope for NAO/AO magic this year I'm thinking.

1952-53 started out with snow in October, November, early December and New years Eve...A little bit more the first half of January and that was it...There was a big change in the pattern after that...The AO index from Dec-Mar was -1.827, -1.036, -0.249, +1.068...The PDO from Dec-Feb was 0.04, -0.57, -0.07...It was a weak enso but it was a second year weak nino...

Link to comment
Share on other sites
  • Replies 220
  • Created
  • Last Reply
tacoman25

tacoman25

Posted
Posted

You're right, 52-53 was only weakly negative. 1951 has been one of my primary analogs through this past summer and it looks like it may be a good one going forward. The august PDO value is more strongly negative than last month, which isn't good news:

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

This puts 12-13 closest to 51-52 PDO wise if we have a weak nino. I can see the PDO warming over the next few months, but usually by September we see some indication of reversal, and we've gone the wrong direction. Going to have to hope for NAO/AO magic this year I'm thinking.

Well, I know you are knowledgable about solar, and I think you'd probably agree that in that respect, we are probably in better shape for -AO blocking this coming winter than was the case in 1951-52.

Some people are not aware that even though the U.S. torched Jan-Feb last winter, much of the NH was quite cold thanks to a very healthy -AO. So I think the tendency is still definitely towards some nice high latitude blocking, and I would be surprised to see the U.S. get the short end of the stick two winters in a row...especially with a change in ENSO.

Link to comment
Share on other sites
weathafella

weathafella

Posted
  • Author
Posted

Let's compare 9/17, the day this thread started to today.

9/17:

ims2012261.gif

9/20: Not much difference in ice yet and of course snow waxes and wanes this time of year still.

cursnow.gif

This post will auto update the current picture so we'll see from day 1 to the present as we roll forward in one post.

Here's the progress over the last 9 days.

Link to comment
Share on other sites
Analog96

Analog96

Posted
Posted

1952-53 started out with snow in October, November, early December and New years Eve...A little bit more the first half of January and that was it...There was a big change in the pattern after that...The AO index from Dec-Mar was -1.827, -1.036, -0.249, +1.068...The PDO from Dec-Feb was 0.04, -0.57, -0.07...It was a weak enso but it was a second year weak nino...

Would you say that 1989-90 is a fair analog for 1952-53? Or was 1989 colder?

Link to comment
Share on other sites
asthut

asthut

Posted
Posted

I like the 2006-07 analog. Check out the SST Anomalies right now and compare them to October of 2006. They are very similar. In that year we also transitioned out of a la nina and phased into an el nino. PDO was a touch on the positive side that year. I am not concerned though because the SST anomalies look so similar. Also in the mid 2000's we started the transition toward a - decadal period of PDO. NAO/AO could be the deal breaker though as it was positive in 06-07. Cool SST in the mid-Atlantic have shown correlation with a negative NAO. Take a look at the anomalies in the mid-Atlantic during the last few weeks... We are trending cooler.

Link to comment
Share on other sites
HM

HM

Posted
Posted

Glad that we're below normal so far. I want it to stay below normal through about Oct 10th, then take off!

I'm not. Climatologically, snow barely reaches 60° at the start of October. I would, at the very least, want the snow cover north of there to start off normal so that it is more likely to expand/build southward throughout the month in a self-sufficient way. Remember, the latitudes that correlate (change in snow and AO) are from 60N southward which is basically southern Siberian on down (I believe to 25N). The longitude covers everywhere from the PM to DL.

Link to comment
Share on other sites
Mallow

Mallow

Posted
Posted

I'm not. Climatologically, snow barely reaches 60° at the start of October. I would, at the very least, want the snow cover north of there to start off normal so that it is more likely to expand/build southward throughout the month in a self-sufficient way. Remember, the latitudes that correlate (change in snow and AO) are from 60N southward which is basically southern Siberian on down (I believe to 25N). The longitude covers everywhere from the PM to DL.

That's true. Thanks for the correction. :)

So, I want snow down to 60N, but no further south, until the second week of October then. ;)

Link to comment
Share on other sites
HM

HM

Posted
Posted

That's true. Thanks for the correction. :)

So, I want snow down to 60N, but no further south, until the second week of October then. ;)

lol yeah something like that. :)

The one thing 2009 had that a lot of other years did not was the rapid/above normal expansion toward Europe and on the southern edge late October. There is something to be said about other climate factors, like ENSO, possibly aiding in favorable circulation for something like this to happen. Simply running ENSO correlations in the autumn show how an El Niño could help build the western and southern extent in October but it obviously isn't the whole story.

Besides snow cover, I want to see a stronger Brewer Dobson Circulation than last year, that's for sure. While it is still very early to say for sure, I see no signs yet of last year's regime changing in this department. But that statement is almost meaningless at this point in time. Funny, as I said this, I noticed an elevated proton flux from the sun...sigh...

Link to comment
Share on other sites
GaWx

GaWx

Posted
Posted

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.

Link to comment
Share on other sites
tacoman25

tacoman25

Posted
Posted

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.

The eastern regions of the PDO area were still quite warm in September, which is probably the main reason for the big negative number.

However, I trust the JISAO numbers more in comparison to historical figures for a variety of reasons. I think NOAA tends to have the more recent PDO numbers too low, from at least the 1990s on.

I could be wrong, but I don't think we will have a big drop in the Sep number for JISAO. There have only been three years that have been -2 or lower: 1933, 1950, and 1961.

Link to comment
Share on other sites
icebreaker5221

icebreaker5221

Posted
Posted

Big ramp up the first 6 days of October in Siberian snow. From solidly below to near normal. The next 10-15 days may well be the most critical.

Looks like a couple of quick-hitting "clipper-like" systems will sweep across Siberia the next couple days and build upon the snowpack in the short term.

Probably some melt after that in the 6-10 day, looking awfully ridgy (below). Beyond that they should get back into a better pattern for building up the snowpack, but whether the rate of snowcover growth is above or below climo is tough to say at this point.

post-378-0-42283700-1349633591_thumb.gif

Link to comment
Share on other sites
Typhoon Tip

Typhoon Tip

Posted
Posted

Actually we kinda want snowcover to start off below normal in Siberia for October. Cohen's latest paper, as I mentioned earlier, shows a much stronger correlation with the change in snowcover during the month of October than the average snowcover for the month.

http://web.mit.edu/j...Jones_GRL11.pdf

I've been waiting for a reputable source to acknowledge this suggestion for year! I have seen it in the numbers my self that rate of change tells more about the system then static measures - it's intuitively correct that way, too.

I have posted of this in the past; not sure if here or in the antiquated Eastern site -

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...