October Pattern Suggests Stronger Winter 13-14 EPO Blocking Than NAO and AO

[forkyfork]

the pacific is horrible for snow mongers

[Cfa]

the pacific is horrible for snow mongers

Muy bien.

[Snow_Miser]

The +EPO is pretty atrocious. The good news though is that there is some signs for a weak +PNA on the longer range ensembles. Also some signs of below normal height anomalies into the east. Still a pretty big signal for a impressive -NAO.

http://www.meteo.psu.edu/~fxg1/ENSHGTAVGNH_12z/f312.html

[SnowGoose69]

the pacific is horrible for snow mongers

 

I'm more worried about the Pacific as far as the lack of any resemblance of an El Nino since what seems like the Palaeozoic ERA at this point, we're likely again to have all sorts of problems getting any southern stream action going...the one thing we probably won't have though which we did last winter if we end up in a similar pattern is that insane tendency for systems coming out of the Midwest to get sheared to crap as they came East.  The ATL SST pattern also looks very bad right now, there is cooler water near Iceland/Greenland, very warm water off SERN Canada...the area from off NRN SAmerica to Africa below 30N is not terrible, there is potential for this to go above normal, if that occurs we could see semblance of the necessary tripole for a -NAO but it looks really bad right now

[Isotherm]

I'm more worried about the Pacific as far as the lack of any resemblance of an El Nino since what seems like the Palaeozoic ERA at this point, we're likely again to have all sorts of problems getting any southern stream action going...the one thing we probably won't have though which we did last winter if we end up in a similar pattern is that insane tendency for systems coming out of the Midwest to get sheared to crap as they came East.  The ATL SST pattern also looks very bad right now, there is cooler water near Iceland/Greenland, very warm water off SERN Canada...the area from off NRN SAmerica to Africa below 30N is not terrible, there is potential for this to go above normal, if that occurs we could see semblance of the necessary tripole for a -NAO but it looks really bad right now

 

 

Agreed the Atlantic looks horrendous, the tropical Pacific is ok, the NPAC is probably our most favorable SSTA region right now (specifically the NE PAC). However, I don't like the strong warm anomalies south of the Aleutians.

[uncle W]

it helps when October is colder than average...15 of the coldest/snowiest winters had a warm October three times...The other 12 were near or below average...

 

[Isotherm]

Good post Unc and strongly agree. October temperature pattern is a very good correlator most years. Early guidance indicates a cool start but too soon to tell if it will hold.

[uncle W]

Good post Unc and strongly agree. October temperature pattern is a very good correlator most years. Early guidance indicates a cool start but too soon to tell if it will hold.

there are the exceptions like 1988...I'm still looking for a cool first half of October like 1964 but that month ended on a mild note...1964 had a cool first half of August, October and December...late month warm spells happened all three months...I think more or less it will be the pattern as of now...

[SnowGoose69]

Agreed the Atlantic looks horrendous, the tropical Pacific is ok, the NPAC is probably our most favorable SSTA region right now (specifically the NE PAC). However, I don't like the strong warm anomalies south of the Aleutians.

 

I forgot to mention the GOA anomalies and off BC are actually looking good, that may be the warmest anomalies I can recall out there this late into the Sept-Nov period maybe since 2002.

[Isotherm]

Regarding the October to winter NAO relationship, since 2002 the blocking that we've seen in October has tended to foretell DJF -NAO. However, in my research looking at the entire period of 1950-present, there's actually a 66% inverse correlation between the October NAO modality and ensuing DJF, with a 67% positive correlation in November b/t the NAO and DJF NAO. So if we examine a larger sample of years, we'd actually want the -NAO to hold off until November. But if Chris' October relationship since 2002 holds, then a -NAO October is better. Should be interesting to see how things unfold, of course these correlations are only a small piece of the puzzle. For me, I'm personally hoping for a colder than normal October with a +NAO, +PNA, followed by a -NAO November with temps less of a concern.

[uncle W]

I deleted my last post...I was using AO numbers for NAO numbers...The NAO was below -1.5 which is a low number but not as low as -2.000...

[Snow_Miser]

The Euro are GFS are developing some pretty impressive blocking over Greenland.

 

[bluewave]

Early indications for the winter of 2013-2014 are that we will see some degree of a -EPO/-NAO/-AO

pattern based on what we are seeing so far in October. The first guess is that the winter will

be a blend of 2002-2003, 2003-2004, 2006-2007, 2009-2010, and 2012-2013. This October

500 mb method really can't narrow down how much snowfall we will see with very variable 

years ranging from 2006-2007 to 2009-2010. I will update the October map in 2 weeks when 

we get the final data to narrow it down better. As always, we will have to wait and see if

the pattern since 2002 repeats.

 

October 2013 so far

 

 

Early guess analog group October

 

 

Early guess winter analog group

 

[Isotherm]

The fact that we're seeing some northern hemispheric blocking in the form of negative EPO / negative NAO is probably a good sign. I think it's too early say whether this will be the dominate signal for DJF though. November is a very important month; we'll have to see if the blocking persists overall the next several weeks. For me, I would have rather seen the -NAO/AO hold off until November.

 

Early indications for the winter of 2013-2014 are that we will see some degree of a -EPO/-NAO/-AO

pattern based on what we are seeing so far in October. The first guess is that the winter will

be a blend of 2002-2003, 2003-2004, 2006-2007, 2009-2010, and 2012-2013. This October

500 mb method really can't narrow down how much snowfall we will see with very variable 

years ranging from 2006-2007 to 2009-2010. I will update the October map in 2 weeks when 

we get the final data to narrow it down better. As always, we will have to wait and see if

the pattern since 2002 repeats.

 

October 2013 so far

 

13.gif

 

Early guess analog group October

 

OCT.png

 

Early guess winter analog group

 

WIN.png

[bluewave]

The fact that we're seeing some northern hemispheric blocking in the form of negative EPO / negative NAO is probably a good sign. I think it's too early say whether this will be the dominate signal for DJF though. November is a very important month; we'll have to see if the blocking persists overall the next several weeks. For me, I would have rather seen the -NAO/AO hold off until November.

 

The best that this method can say now is that 500 mb heights may be above normal in those regions for DJF on average.

It doesn't really say much about the exact index levels or how much snow we will see here this winter. If the 2002 on pattern

holds, it would exclude years like 2007-2008 and 2011-2012 which had lower heights in October and the following winters with a  +AO/+NAO dominant pattern.

[Wxoutlooksblog]

The fact that we're seeing some northern hemispheric blocking in the form of negative EPO / negative NAO is probably a good sign. I think it's too early say whether this will be the dominate signal for DJF though. November is a very important month; we'll have to see if the blocking persists overall the next several weeks. For me, I would have rather seen the -NAO/AO hold off until November.

I agree with this. Nine out of ten times there is a major pattern change sometime during late November or December.  Not that the pattern we're in now would necessarily yield an epic snowy winter. I do not think that it would. But from the standpoint of dominant blocking, we have some now, and it is usually hard to maintain it for a long duration, especially without an El Nino.

WX/PT

[uncle W]

Winter's high and low daily AO index from 12/1 to 3/20...

winter..........peak date.......valley date.....

1979-80....+5.040 12/02/79.....-3.705 01/24/80

1980-81....+3.233 02/03/81.....-4.318 03/04/81

1981-82....+3.361 02/09/82.....-3.804 12/30/81

1982-83....+4.426 01/08/83.....-3.410 02/06/83

1983-84....+4.460 12/27/83.....-3.706 03/13/84

1984-85....+3.565 12/09/84.....-6.226 01/19/85

1985-86....+2.918 03/04/86.....-3.894 02/06/86

1986-87....+2.293 12/02/86.....-3.507 03/09/87

1987-88....+2.230 01/02/88.....-2.314 02/28/88

1988-89....+5.582 01/14/89.....-0.318 03/14/89

1989-90....+5.911 02/26/90.....-3.482 12/10/89

1990-91....+3.502 12/26/90.....-3.381 03/09/91

1991-92....+4.704 12/17/91.....-2.597 12/04/91

1992-93....+5.245 01/14/93.....-2.228 03/02/93

1993-94....+3.666 03/14/94.....-3.503 02/24/94

1994-95....+3.198 12/05/94.....-3.116 03/04/95

1995-96....+3.517 02/22/96.....-4.353 12/19/95

1996-97....+3.712 03/09/97.....-3.377 12/30/96

1997-98....+1.916 01/01/98.....-4.269 01/10/98

1998-99....+3.244 12/25/98.....-3.856 03/10/99

1999-00....+3.886 01/29/00.....-2.118 02/18/00

2000-01....+2.939 02/14/01.....-4.854 02/25/01

2001-02....+3.690 03/06/02.....-3.293 12/28/01

2002-03....+2.498 01/15/03.....-3.575 01/22/03

2003-04....+2.597 03/17/04.....-4.387 01/17/04

2004-05....+4.703 01/05/05.....-4.337 02/26/05

2005-06....+3.339 01/11/06.....-3.569 12/05/05

2006-07....+3.990 01/05/07.....-2.184 02/04/07

2007-08....+4.598 01/24/08.....-2.468 01/02/08

2008-09....+3.256 01/11/09.....-3.178 02/03/09

2009-10....+1.188 03/19/10.....-5.821 12/21/09

2010-11....+3.914 02/04/11.....-5.265 12/18/10

2011-12....+4.350 12/02/11.....-3.451 01/28/12

2012-13....+1.748 02/03/13.....-5.688 03/20/13

 

[forkyfork]

a few recent january record cold events in the nyc area. all had 850 mb temps below -25c at some point

[forkyfork]

every january record low which was recent enough to view on reanalysis data had positive anomalies in the EPO region. others have mentioned the importance of the EPO and northeast cold for years on this forum

http://www.erh.noaa.gov/okx/climate/almanacs/ewrjan.htm

[NEG NAO]

IMO any forecaster and there has been at least one -accuweather - who is forecasting a mild December has a good chance of busting - 2 reasons - we have had 2 very mild Decembers in a row which is very rare and the NAO and EPO  has been trending negative - plus we are more or less in La Nada - different then last year - here are the monthly averages :

 

http://www.erh.noaa.gov/okx/climate/records/monthannualtemp.html

[yhbrooklyn]

we have had 2 very mild Decembers in a row which is very rare

 

Just FYI, 2011-2012 was the 18th time that back to back Decembers were 38.0° or higher.

Of the previous 17, the average temp the following year was 35.9°. The current normal December is 37.5°, so this obviously represents colder than normal.

However, there have been some real torches following the two warm Decembers, most notably December 1998 at a balmy 43.2°

 

The full list (first number is the consecutive warm Decembers, second number is the following year's December temp).

 

1911-1912 38.7

1912-1913 31.6

1931-1932 32.7

1940-1941 31.1

1948-1949 35.0

1951-1952 41.3

1952-1953 35.9

1956-1957 29.4

1971-1972 39.0

1972-1973 39.4

1973-1974 35.9

1978-1979 32.5

1986-1987 35.9

1990-1991 37.9

1996-1997 43.2

1997-1998 40.0

1998-1999 31.1

2011-2012 ???

[NEG NAO]

 

Just FYI, 2011-2012 was the 18th time that back to back Decembers were 38.0° or higher.

Of the previous 17, the average temp the following year was 35.9°. The current normal December is 37.5°, so this obviously represents colder than normal.

However, there have been some real torches following the two warm Decembers, most notably December 1998 at a balmy 43.2°

 

The full list (first number is the consecutive warm Decembers, second number is the following year's December temp).

 

1911-1912 38.7

1912-1913 31.6

1931-1932 32.7

1940-1941 31.1

1948-1949 35.0

1951-1952 41.3

1952-1953 35.9

1956-1957 29.4

1971-1972 39.0

1972-1973 39.4

1973-1974 35.9

1978-1979 32.5

1986-1987 35.9

1990-1991 37.9

1996-1997 43.2

1997-1998 40.0

1998-1999 31.1

2011-2012 ???

 

Never in recorded history has there been 3 Decembers in a row  with the average temp 40 degrees or higher. Average December temp is 37.5 as you say - anything lower then 40 degrees avg . is close to average NOT what would be considered "mild:" so it stands to reason we will not have a mild December which I consider to be at least 2.5 degrees or more above average

[Guest Pamela]

Never in recorded history has there been 3 Decembers in a row  with the average temp 40 degrees or higher. Average December temp is 37.5 as you say - anything lower then 40 degrees avg . is close to average NOT what would be considered "mild:" so it stands to reason we will not have a mild December which I consider to be at least 2.5 degrees or more above average

 

Its simply very hard to get consistent cold in December in the Greater New York area because the general storm track is usually to our west up into the Great Lakes...meaning warm frontal passage after warm frontal passage.  To get a cold December around here...it would probably help to have a dry pattern. December is the stormiest month of the year overall across the continental U.S...and how many snowstorms for Denver or Chicago are snowstorms for NYC?  Practically none.

[uncle W]

Never in recorded history has there been 3 Decembers in a row  with the average temp 40 degrees or higher. Average December temp is 37.5 as you say - anything lower then 40 degrees avg . is close to average NOT what would be considered "mild:" so it stands to reason we will not have a mild December which I consider to be at least 2.5 degrees or more above average

twice we had four consecutive Decembers 38.3 or higher...1971-74 and 1996-99...warm decembers usually mean less seasonal snow than average...

[yhbrooklyn]

Never in recorded history has there been 3 Decembers in a row  with the average temp 40 degrees or higher. Average December temp is 37.5 as you say - anything lower then 40 degrees avg . is close to average NOT what would be considered "mild:" so it stands to reason we will not have a mild December which I consider to be at least 2.5 degrees or more above average

It's 37.5 now, but was considerably colder in previous 30 year averages.

The 30 year 1901-1930 December average was 34.8.

I used a semi-arbitrary 38.0 and greater number because it seemed warm, but relative to normal, it was much warmer pre-1980.

As for 40 and higher, you're right that we've never had 3 Decembers in a row, but we did have 3 of 4 from 1996-1999.

Here is the list of 3+ consecutive Decembers with temps 38.0 and above:

 

1911-13 - 39.4, 39.3, 38.7

1951-53 - 38.6, 38.4, 41.3

1971-74 - 40.8, 38.5, 39.0, 39.4

1996-99 - 41.3, 38.3, 43.2, 40.0

[uncle W]

the 1990's had was the warmest December decade...I remember when the normal December temp was 35.5 for the 1941-70 period...the long term average 1870-2012 must be at 35.6 or 35.7...

December 1869-2010 Central Park...
there is a noticeable lack of single digit temperatures since the 1980's...
decade....ave.temp....high..low.....ave.max/min....max..min...precipitation...snowfall
1870's......32.7......37.4......24.9..........................64......-2...2.88"...6.7"
1880's......33.6......40.0......26.5......57.3.....7.9....67......-6...3.28"...7.1"
1890's......35.9......42.3......29.9......58.8...12.0....66.......8...2.97"...4.3"
1900's......34.8......38.9......30.3......57.1...13.6....64.......4...3.95"...6.2"
1910's......34.1......39.4......25.0......59.4...10.8....64....-13...3.80"...7.5"
1920's......35.5......42.0......28.9......59.0...13.2....68.......7...3.49"...4.2"
1930's......35.9......41.0......30.0......61.2...11.7....68......-6...2.86"...4.3"
1940's......35.4......39.4......31.0......59.5...11.7....70......-4...3.39"...9.1"
1950's......36.8......41.3......29.4......59.7...12.0....67.......5...3.49"...4.7"
1960's......34.8......40.5......30.9......61.6...12.9....68.......4...3.70"...7.4"
1970's......37.4......41.1......29.9......61.6...17.6....67.......9...4.63"...1.7"
1980's......36.6......43.8......25.9......61.0...11.8....72......-1...3.14"...2.1"
1990's......39.5......43.2......32.4......64.0...16.5....75.....10...4.04"...2.9"
2000's......37.7......44.1......31.1......62.9...16.6....71.....11...4.45"...7.8"
2010's......39.2......43.3......32.8......61.3...23.0....62.....19...4.35"...6.8"
1870-
2009.........35.6......41.0......29.0......60.2...12.9....68.......2...3.58"...5.4"
1980-
2009.........37.9......43.7......29.8......62.6...15.0....73.......7...3.88"...4.3"

[NEG NAO]

You can see a trend developing with the NAO pattern - the last few months the NAO has been trending positive for about month then negative for about a month we are just exiting a month long mostly negative trend and are entering a forecasted positive trend - lets see how long the positive trend lasts - if it follows the trend we should stay mainly positive in November  to close to Thanksgiving which is the 28th this year and then the big question is will December  be mainly negative or positive NAO - if the trend holds most of December could be negative...

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/nao.sprd2.gif

[Isotherm]

Chris, could this be the year where the 93-94 analog actually works?

 

In all seriousness, that H5 composite for November 1993 does look strikingly similar to the progged pattern over the next couple weeks. Strongly positive AO, NAO, coupled with the maintenance of some degree of EPO ridging. Obviously that doesn't mean we'll be seeing 93-94 evolve, but it'll be interesting to watch nonetheless.

[yhbrooklyn]

Chris, could this be the year where the 93-94 analog actually works?

 

In all seriousness, that H5 composite for November 1993 does look strikingly similar to the progged pattern over the next couple weeks. Strongly positive AO, NAO, coupled with the maintenance of some degree of EPO ridging. Obviously that doesn't mean we'll be seeing 93-94 evolve, but it'll be interesting to watch nonetheless.

For the NYC area, 93-94 was great, but extremely frustrating and dangerous with multiple ice events. I remember scraping my car off constantly.

We did get a good amount of snow, but I'm sure the burbs did much better.

[easternsnowman]

I was also thinking 1993-94 is a possible analog, although the pacific was better that year and let's hope the atlantic cooperates more than that, otherwise we would nede that kind of setup for the pacific to have a decent to good winter.