Very Early Winter 2013-14 Thoughts

[Guest Pamela]

2006-07 winter averaged 36.5 for the 90 day period 12/1 to 2/28...The coldest 30 day period was from late January to late February at 25.8...That means the other 60 days averaged 41.9...Other winters with similar numbers...These winters were one third cold and two thirds mild...

winter.....ave temp.....30 day cold.....other 60 days...

2006-07..........36.5...............25.8...............41.9

1999-00..........36.2...............26.2...............41.2

1953-54..........37.4...............30.3...............41.0

1984-85..........36.4...............27.5...............40.9

1989-90..........35.7...............25.3...............40.9

1994-95..........37.1...............31.5...............40.4

1983-84..........35.2...............26.1...............39.8

1965-66..........35.9...............28.5...............39.6

1956-57..........35.6...............27.8...............39.5

1971-72..........35.1...............28.6...............38.4

 

I recall 2006-07 turning bitter cold after MLK Day...

[NorthShoreWx]

Those are some pretty maps (with possible exceptions of 06 - 07 - 08).  If only the author would get off his duff and do the work for the past few winters.

 

PS Retro axe smiley...haven't used that one in a long time

[NorthShoreWx]

http://www.northshorewx.com/lisnowfallpatterns.asp

 

"In general, the highest annual average snowfalls occur along the north shore from roughly Port Washington in Nassau County eastward through Port Jefferson in Suffolk County."

 

I never did get time to do a more in depth analysis of the available records, but that jackpot zone may need to be shifted eastward just a a bit. 

 

I do keep expecting a winter where western LI clobbers eastern LI, but it hasn't happened yet.  The north shore of most of Nassau doesn't suck either.  At least it didn't used to.

 

Ed

[NorthShoreWx]

Have been living and working here for 11 years now, and that Long Island central north shore maximum is for real. It's protected from the influence of the ocean to the east and south, away from the urban heat island, and generally at higher elevations than the south shore. That area also hit the jackpot in February's blizzard.

 

I'm not sure how much / how often this contributes, but those areas are also 25 or 30 miles farther north than say the south shore of Nassau.

[Guest Pamela]

Those are some pretty maps

 

Yes they are

[uncle W]

I recall 2006-07 turning bitter cold after MLK Day...

you're right...the coldest 30 day period was from 1/21 to 2/19...

[jm1220]

Have been living and working here for 11 years now, and that Long Island central north shore maximum is for real. It's protected from the influence of the ocean to the east and south, away from the urban heat island, and generally at higher elevations than the south shore. That area also hit the jackpot in February's blizzard.

It also catches late-developer storms a little better, such as March 2001 when Riverhead got 18" maybe. It really is very New Englandlike out there in the winters.

[donsutherland1]

Brief morning thought...

 

The Arctic Oscillation (AO) had risen further to +3.153 today. That is its highest reading since April 22, 2013 when the AO stood at +3.244. Since 1950, there have been only 5 previous years during which the AO reached +3.000 or above: 1973, 1975, 1978, 1994, and 2011. Most of those years featured a warm December in much of the East.

 

The composite temperature anomalies using the 1981-2010 base period are below:

 

 

Use of the 1950-1995 base period would show more widespread and larger warm anomalies.

 

With the exception of the 1978 case, all of the above cases saw the AO+ regime develop during a timeframe that extended from the last ten days of October to the first two weeks of November. The current AO+ regime began within that timeframe. The 1978 case saw the AO+ regime commence on 10/10.

 

In addition, summers 1973, 1975, and 1994 saw the AO average > 0. Summer 2013 also had an AO average > 0. Summers 1978 and 2011 had an average AO < 0.

 

In short, while there are some differences among the prior cases--both starting point of the AO+ regime and summer AO figures--the general idea is that such a regime was followed by a warmer than normal December in much of the eastern U.S. The differences between 2013 and 1978 might offer a hint that Winter 2013-14 might not feature the kind of dramatic flip to severe blocking that occurred during 1978-79. Overall, the December outcome from the prior cases offers another piece of possible information to be considered when looking ahead to December.
 

[donsutherland1]

In message #75, I ran partial teleconnection analogs and then applied the years of those partial analogs to December. In message #98, I ran the composite temperature anomalies for December following all November cases with a peak Arctic Oscillation of +3 or above. Both cases featured a warmer than average December in the East.

 

Tonight, just for a very preliminary idea to see how things would look when ENSO was incorporated into the mix, I ran the maps for ENSO and Teleconnections. I ran the maps for North America and for Europe. For purposes of comparison, I also included the 11/8/2013 0z run of the CFSv2.

 

The maps were as follows:

 

 

Although I didn't run the maps for Asia, the ENSO-Teleconnection analogs suggested that much of East Asia (including China, Japan, and parts of Siberia) would wind up cooler than normal in December. That's in contrast to the warm idea shown on the CFSv2.

 

It's important to note that from this far out, neither the ENSO-Teleconnection maps nor the CFSv2 have demonstrated much skill. But what might give somewhat higher confidence than normal in the idea of a warmer idea is the consistency of that idea based on the partial teleconnection analogs since the beginning of November and the December cases following November AO peaks of +3 or above, as has occurred this year.

 

In any case, I'll revisit the data toward the latter part of this month. There's no need to be overly repetitive especially with such a dreary scenario that is coming up time and again.

[uncle W]

a good example of a plus AO winter is 1988-89...From 11/27 to 4/14 there were only two days with a negative AO...12/25 and 3/4...I do not think we will see that this year...I think we will see some periods with a negative AO...

[Isotherm]

In message #75, I ran partial teleconnection analogs and then applied the years of those partial analogs to December. In message #98, I ran the composite temperature anomalies for December following all November cases with a peak Arctic Oscillation of +3 or above. Both cases featured a warmer than average December in the East.

 

Tonight, just for a very preliminary idea to see how things would look when ENSO was incorporated into the mix, I ran the maps for ENSO and Teleconnections. I ran the maps for North America and for Europe. For purposes of comparison, I also included the 11/8/2013 0z run of the CFSv2.

 

The maps were as follows:

 

 

Although I didn't run the maps for Asia, the ENSO-Teleconnection analogs suggested that much of East Asia (including China, Japan, and parts of Siberia) would wind up cooler than normal in December. That's in contrast to the warm idea shown on the CFSv2.

 

It's important to note that from this far out, neither the ENSO-Teleconnection maps nor the CFSv2 have demonstrated much skill. But what might give somewhat higher confidence than normal in the idea of a warmer idea is the consistency of that idea based on the partial teleconnection analogs since the beginning of November and the December cases following November AO peaks of +3 or above, as has occurred this year.

 

In any case, I'll revisit the data toward the latter part of this month. There's no need to be overly repetitive especially with such a dreary scenario that is coming up time and again.

 

 

 

The period November-early December is usually a time in which the winter pattern begins making itself evident; however, there are some years where November is a transitional month AO wise, and the winter regime sets in for December.

 

For example, if we look at two analogs which featured  +3 SD or higher daily AO values in November, 1973-74, and 1978-79, both years flipped to a negative AO in December, and actually featured a negative AO overall for the DJF mean.

 

1973-74 had a negative AO in December and February, making the mean negative.

 

1978-79 had a negative AO all three winter months DJF, following the strongly positive AO in November.

 

The tendency is for a positive AO winter following strongly positive AO periods in November, but there are certainly examples where that is not the case.

 

1973-74 was a strong La Nina, and 1978-79 was neutral ENSO. So speaking ENSO alone, the latter year is a closer match; however, it was following two warm ENSO seasons.

 

So the point here to everyone is that the strongly positive AO period we're seeing is not necessarily the kiss of death in terms of an overall negative AO winter or at the very least periods of negative AO. Trends regarding this winter will become clearer to me in the next couple weeks.

[SACRUS]

Yes they are

 

 

great maps.  What years do you have through?

[Guest Pamela]

great maps.  What years do you have through?

 

 

Lol...what you see is what he's got (2002-03 through 2008-09).

 

http://northshorewx.com/

[Guest Pamela]

Those are some pretty maps (with possible exceptions of 06 - 07 - 08).  If only the author would get off his duff and do the work for the past few winters.

 

 

Would love to see a 2000-01 map...that was a very interesting winter around here with the 3 semi-big storms (12/30, 2/5, & 3/5).

[donsutherland1]

The period November-early December is usually a time in which the winter pattern begins making itself evident; however, there are some years where November is a transitional month AO wise, and the winter regime sets in for December.

 

For example, if we look at two analogs which featured  +3 SD or higher daily AO values in November, 1973-74, and 1978-79, both years flipped to a negative AO in December, and actually featured a negative AO overall for the DJF mean.

 

1973-74 had a negative AO in December and February, making the mean negative.

 

1978-79 had a negative AO all three winter months DJF, following the strongly positive AO in November.

 

The tendency is for a positive AO winter following strongly positive AO periods in November, but there are certainly examples where that is not the case.

 

1973-74 was a strong La Nina, and 1978-79 was neutral ENSO. So speaking ENSO alone, the latter year is a closer match; however, it was following two warm ENSO seasons.

 

So the point here to everyone is that the strongly positive AO period we're seeing is not necessarily the kiss of death in terms of an overall negative AO winter or at the very least periods of negative AO. Trends regarding this winter will become clearer to me in the next couple weeks.

I agree that the current AO+ regime does not guarantee that there won't be a regime change to AO-. However, there's enough evidence to suggest that odds of such an outcome are probably lower than those of a predominantly AO+  pattern. The Snow Advance Index and new October Pattern Index all argue for an AO+ winter. FWIW, my statistical AO analogs also suggest about a 75% change of an AO+ winter.

 

With respect to 1978-79, the 1978 November AO+ case saw the AO+ develop in early October, unlike the current one following a summer where the AO averaged < 0 (unlike 2013). The time of development might have made it more likely that the earlier case was a transitional one.

[Isotherm]

I agree that the current AO+ regime does not guarantee that there won't be a regime change to AO-. However, there's enough evidence to suggest that odds of such an outcome are probably lower than those of a predominantly AO+  pattern. The Snow Advance Index and new October Pattern Index all argue for an AO+ winter. FWIW, my statistical AO analogs also suggest about a 75% change of an AO+ winter.

 

With respect to 1978-79, the 1978 November AO+ case saw the AO+ develop in early October, unlike the current one following a summer where the AO averaged < 0 (unlike 2013). The time of development might have made it more likely that the earlier case was a transitional one.

 

 

Can't disagree with anything there. A number of factors right now point to a general +AO winter. The next several weeks should reveal whether or not this winter's looking to head toward the minority of cases or "fit the bill" of the indicators.

 

Now other indices are a different story. The EPO and NAO will also be important players.

[green tube]

DT seems bullish on the coming winter, of all things. 

a couple weeks ago he posted the work of a guy who had a 30 year back tested theory which predicts the NAO.  based on winds at a particular level in the atmosphere from May to October.  the success rate was extreme. he's predicting a solid neg nao for the winter.

i cant find the post (facebook) now, but DT endorsed the dude's work.

[donsutherland1]

DT seems bullish on the coming winter, of all things. 

a couple weeks ago he posted the work of a guy who had a 30 year back tested theory which predicts the NAO.  based on winds at a particular level in the atmosphere from May to October.  the success rate was extreme. he's predicting a solid neg nao for the winter.

i cant find the post (facebook) now, but DT endorsed the dude's work.

The graduate student who identified the possible relationship has posted at AmericanWx in the past. His handle was/is Wxmidwest. The wintertime NAO can sometimes diverge from the AO, so we'll see what happens.

[uncle W]

latest MEI index was +0.094

2013	.042	-.163	-.171	.009	.069	-.298	-.469	-.614	-.19	.094

With the mei now in the plus side the oni should start rising also...This winter might end up a neutral plus afterall...

[IntenseBlizzard2014]

Interesting. Nearly 100% of Canada is covered in snow. 

 

[NEG NAO]

NAO

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

PNA

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

AO

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif

 

in addition to Canada mostly covered in snow - all indicies are forecasted to move to more favorable positions for cold/snow in the east the next couple weeks - let's see if they deliver the goods

Interesting. Nearly 100% of Canada is covered in snow. 

 

Canada and Siberia's Snowfall Cover 11-12-2013.jpg

[Isotherm]

Canada snow covered at this time of year means about as much as T-storms in Florida in mid August. Meteorological winter's a couple weeks away, I think the snow cover tracking period is over.

[NEG NAO]

6Z GFS is continuing the current pattern of cold shots every few days followed by brief warm ups - next weeks arctic outbreak is just as cold if not a few degrees colder then this weeks - also the GFS has cut back on the precip quite a bit from yesterday

 

http://wxweb.meteostar.com/sample/sample.shtml?text=KEWR

[donsutherland1]

The following are some statistics related to the AO, ENSO and New York City's seasonal snowfall (1950-51 through 2012-13):