Winter 2014-2015 Medium-Term Discussion

[griteater]

Full winter for the pre 1950 ++PDO Nov years from bigmack

 

[WidreMann]

There appears to be a stark difference between pre-1950 and post-1950 behavior. What major oscillation shifted?

[griteater]

There appears to be a stark difference between pre-1950 and post-1950 behavior. What major oscillation shifted?

 

Yeah, that's pretty wild...here's the temp anomaly map for those pre-1950 ++PDO winters (or at least ++PDO Nov prior to the winter)

 

[griteater]

The one milder exception in the Northeast US. Strong -NAO still dominated.

 

 

By the way Isotherm, 59-60 was legendary down here, especially Feb/Mar.  Snowiest winter on record here in Charlotte.  Here's a photo from Boone, NC in March of 1960

 

[Rainman]

Wildly different look in the Arctic Circle with much lower heights back in the pre-1950 years.

[SnowGoose69]

Part of me wonders if that is accurate, maybe the PDO indices from pre 1950 are wrong hence the total different patterns

[Polar Vortex 2014]

Jan for the pre 1950 ++PDO Nov years added by bigmack

 

 

Jan for the post 1950 ++PDO Nov years from Isotherm

 

Jan for the pre 1950 ++PDO Nov years added by bigmack

 

 

Jan for the post 1950 ++PDO Nov years from Isotherm

 

What about 1997-1998? Mack added it to his data set, and Isotherm omitted it. According to this site, November 1997 had a PDO of +1.12, which is higher than 1959-60 which was included in Isotherm's dataset. http://jisao.washington.edu/pdo/PDO.latest

[Isotherm]

Interestingly enough, even though the pre-1950 years have a mean +NAO / AO signal, the USA temperature departures appear to take on a look similar to last winter due to the -EPO signal present in those pre-1950 cases. The resultant is a temperature pattern that really isn't too much warmer than the post 1950 years.

 

Grit, here's the pre 1950 years with respect to the latest 1980-2010 normal (which I think is probably the most relevant period to use right now):

 

Cold save for a slight warm anomaly in the SE US:

 

 

 

When we average all of the > +1 PDO Novembers since 1900, the resultant DJF is cold nationwide:

 

 

 

 

 

 

 

 

[Isotherm]

What about 1997-1998? Mack added it to his data set, and Isotherm omitted it. According to this site, November 1997 had a PDO of +1.12, which is higher than 1959-60 which was included in Isotherm's dataset. http://jisao.washington.edu/pdo/PDO.latest

 

 

You're right, I missed 1997. However, after adding it into the mix, the 500mb composite remains very similar as 1997-98 featured a fairly strong -AO/NAO in the means. Torched due to the super Nino, of course.

 

Composites including 97:

 

 

 

 

[Isotherm]

By the way Isotherm, 59-60 was legendary down here, especially Feb/Mar.  Snowiest winter on record here in Charlotte.  Here's a photo from Boone, NC in March of 1960

 

 

 

Wow. I guess the storm track must have been suppressed that year due to the strong -NAO. How much snow did you get on the season? That's impressive.

[GaWx]

By the way Isotherm, 59-60 was legendary down here, especially Feb/Mar.  Snowiest winter on record here in Charlotte.  Here's a photo from Boone, NC in March of 1960

 

 

Whereas it wasn't anywhere near the snowiest on record at Atlanta, they did have an amazing three major winter storms during the first half of March, 1960: two major ZR's/IP and one major SN!! Three major winter storms within two weeks is simply amazing for ATL. March was an amazing 11 below normal and was the coldest month there since Feb. of 1958!! It was 1.5 below the normal for Jan! That winter's measurable wintry precip. was all received in March.

[griteater]

Wow. I guess the storm track must have been suppressed that year due to the strong -NAO. How much snow did you get on the season? That's impressive.

 

Charlotte had a measly 22 inches.  Boone at 3,333 ft recorded 82 inches in Feb-Mar alone and had a snow depth of 44 inches in mid-March.  High drifts prevented continuous obs at the high peaks (Mt Mitchell).  National Guard choppers had to drop supplies in rural mtn areas.

 

http://www.erh.noaa.gov/gsp/localdat/cases/2010/Review_Feb-Mar_1960.pdf

http://www.easternsnow.org/proceedings/2006/perry_and_konrad.pdf

[donsutherland1]

Part of me wonders if that is accurate, maybe the PDO indices from pre 1950 are wrong hence the total different patterns

Could be the AMO, too.

[donsutherland1]

A Winter Nightmare from the Past

 

For the past seven days, a growing amount of light has swept across Menorahs everywhere. For some snow lovers, this growing light perhaps symbolized what the ensembles and operational guidance had been promising: a big pattern change ahead with numerous snowfall opportunities.

 

Now, as Hanukkah is concluding and Christmas lies just ahead, a large part of the East will be swept with moderate to heavy rains, gusty winds, and unseasonably mild temperatures. Dreams of a white Christmas will be washed away by the rain, not to mention the tears of heartbroken snow geese in the face of this cruel warmth.

 

But there is even worse. The latest teleconnection forecasts offer only more misery. Forecasts for a deeply negative EPO have been withdrawn almost as suddenly as they had first appeared. The PNA is now forecast to creep into negative territory.

 

What’s that immense tower in the distance? It dwarfs even the world’s tallest structure. Look closer. That’s the latest GFS ensemble forecast for the Arctic Oscillation. One member even takes the AO toward +5 during the first week in January.

 

 

 

Perhaps, the vendors can offer some relief. Unfortunately, little is to be found there. DT has now ominously highlighted the strongly negative QBO (though he has not written off the winter). JB has moved from discussions of coming cold and deep snows, skipping the changing climate, straight to the “Beast of Bakersfield.”

 

While many at AmericanWx may not be old enough to recall it, there once was an El Niño winter that started bold and cold in November. It did so as the QBO was falling steadily. Surely, festive scenes of sleigh rides, skiing, and snowmobiling, not to mention snow-clogged streets and snow-covered fences lay just ahead.

 

At least that’s what many might have thought. But then, December witnessed a dramatic turnaround. December was as warm as November was cold.

 

 

Was this the end?

 

In January, the QBO continued to fall. The El Niño persisted. A 13-day period of blockiness managed to develop, but the blocking was not very severe. Afterward, the AO returned to its predominantly positive state.

 

Once the book was closed on meteorological winter, it proved to be a book snow lovers wished had never been written. Where was Sony Pictures to pull that book prematurely? In the end, December had foretold the rest of the winter story with stunning prescience. January and February were defined by continued widespread warmth.

 

 

 

As the calendar advanced toward spring, winter finally tried to awaken from its all too long slumber. Days were now growing longer and winter’s opportunities were dwindling fast. The East Coast witnessed cold anomalies and above normal March snowfall. But that late and regionally-limited rally could not salvage what had once appeared to have been a promising winter back in November. For those who are interested, that winter was 1991-92.

 

Are we in the early stages of a replay of this nightmare? Certainly, the latest AO forecasts are extremely frightening. For now, though, it’s still a little premature to make that call and I’m not yet ready to give up on the still young winter of 2014-15. But one can no longer deny the reality that a warm winter has now rudely barged into the realm of possibility. Still, the El Niño this time around is weaker than it was in 1991-92. Perhaps, that detail will prove crucial in the longer-run.

 

To all, enjoy the rest of Hanukkah, have a great Christmas and New Year.

[binovc]

Thanks Dom, I remember that winter well here in the Great Lakes

[WXinCanton]

Doesn't bode well for the OPI.   Looks like the last 2 winters could have its worst verification.

[Srain]

Meanwhile those of us along the Southern tier of States continue to have a potent Winter Storm signal for New Years Eve into the first days of January 2015. ABQ offered this snip form their morning AFD.

 

GUIDANCE THEN INDICATES A POTENTIALLY SIGNIFICANT WINTER STORM
SYSTEM EVOLVING VERY SLOWLY OVER THE AREA EARLY NEXT WEEK. THIS
ONE BEARS WATCHING AS PLENTY OF COLD AIR IS IN PLACE AND THE UPPER
FORCING IS NEARLY STATIONARY TO THE WEST OF NEW MEXICO FOR SEVERAL
DAYS. THE MOISTURE SOURCE WILL BE THE INGREDIENT TO QUESTION...BUT
THE POTENTIAL EXISTS FOR A BIG SNOW EVENT AROUND NEW YEARS.
 

[CoastalWx]

A lot of the guidance looked pretty cold for the west and central. I suspect January will not look like those composites. This is a Nina pattern in an overall El Nino right now. The models also don't retro the ridge as much as the 00z guidance did yesterday. It's a massive +NAO but in a position similar to last winter for the time being. I think eventually it gets more Nino like, but for now..the MJO is saying not yet.

[buckeyefan1]

A Winter Nightmare from the Past

 

To all, enjoy the rest of Hanukkah, have a great Christmas and New Year.

Great write up as usual     Merry Holidays to you Don!  

[donsutherland1]

A lot of the guidance looked pretty cold for the west and central. I suspect January will not look like those composites. This is a Nina pattern in an overall El Nino right now. The models also don't retro the ridge as much as the 00z guidance did yesterday. It's a massive +NAO but in a position similar to last winter for the time being. I think eventually it gets more Nino like, but for now..the MJO is saying not yet.

I agree. I'm not yet ready to write off winter.

[donsutherland1]

Meanwhile those of us along the Southern tier of States continue to have a potent Winter Storm signal for New Years Eve into the first days of January 2015. ABQ offered this snip form their morning AFD.

 

GUIDANCE THEN INDICATES A POTENTIALLY SIGNIFICANT WINTER STORM

SYSTEM EVOLVING VERY SLOWLY OVER THE AREA EARLY NEXT WEEK. THIS

ONE BEARS WATCHING AS PLENTY OF COLD AIR IS IN PLACE AND THE UPPER

FORCING IS NEARLY STATIONARY TO THE WEST OF NEW MEXICO FOR SEVERAL

DAYS. THE MOISTURE SOURCE WILL BE THE INGREDIENT TO QUESTION...BUT

THE POTENTIAL EXISTS FOR A BIG SNOW EVENT AROUND NEW YEARS.

 

This should be a pretty exciting possibility. Hopefully, it will materialize.

[40/70 Benchmark]

Don, you're a talented writer; however I do not particularly care for the tone of your piece.

[Ottawa Blizzard]

A Winter Nightmare from the Past

 

For the past seven days, a growing amount of light has swept across Menorahs everywhere. For some snow lovers, this growing light perhaps symbolized what the ensembles and operational guidance had been promising: a big pattern change ahead with numerous snowfall opportunities.

 

Now, as Hanukkah is concluding and Christmas lies just ahead, a large part of the East will be swept with moderate to heavy rains, gusty winds, and unseasonably mild temperatures. Dreams of a white Christmas will be washed away by the rain, not to mention the tears of heartbroken snow geese in the face of this cruel warmth.

 

But there is even worse. The latest teleconnection forecasts offer only more misery. Forecasts for a deeply negative EPO have been withdrawn almost as suddenly as they had first appeared. The PNA is now forecast to creep into negative territory.

 

What’s that immense tower in the distance? It dwarfs even the world’s tallest structure. Look closer. That’s the latest GFS ensemble forecast for the Arctic Oscillation. One member even takes the AO toward +5 during the first week in January.

 

 

 

Perhaps, the vendors can offer some relief. Unfortunately, little is to be found there. DT has now ominously highlighted the strongly negative QBO (though he has not written off the winter). JB has moved from discussions of coming cold and deep snows, skipping the changing climate, straight to the “Beast of Bakersfield.”

 

While many at AmericanWx may not be old enough to recall it, there once was an El Niño winter that started bold and cold in November. It did so as the QBO was falling steadily. Surely, festive scenes of sleigh rides, skiing, and snowmobiling, not to mention snow-clogged streets and snow-covered fences lay just ahead.

 

At least that’s what many might have thought. But then, December witnessed a dramatic turnaround. December was as warm as November was cold.

 

 

Was this the end?

 

In January, the QBO continued to fall. The El Niño persisted. A 13-day period of blockiness managed to develop, but the blocking was not very severe. Afterward, the AO returned to its predominantly positive state.

 

Once the book was closed on meteorological winter, it proved to be a book snow lovers wished had never been written. Where was Sony Pictures to pull that book prematurely? In the end, December had foretold the rest of the winter story with stunning prescience. January and February were defined by continued widespread warmth.

 

 

 

As the calendar advanced toward spring, winter finally tried to awaken from its all too long slumber. Days were now growing longer and winter’s opportunities were dwindling fast. The East Coast witnessed cold anomalies and above normal March snowfall. But that late and regionally-limited rally could not salvage what had once appeared to have been a promising winter back in November. For those who are interested, that winter was 1991-92.

 

Are we in the early stages of a replay of this nightmare? Certainly, the latest AO forecasts are extremely frightening. For now, though, it’s still a little premature to make that call and I’m not yet ready to give up on the still young winter of 2014-15. But one can no longer deny the reality that a warm winter has now rudely barged into the realm of possibility. Still, the El Niño this time around is weaker than it was in 1991-92. Perhaps, that detail will prove crucial in the longer-run.

 

To all, enjoy the rest of Hanukkah, have a great Christmas and New Year.

I was 11 years old that winter and can thus only vaguely remember it. I do remember a brief cold period in January of 1992 in Toronto and, from what I can see from the stats, February 1992 was quite cold in Ottawa. I've read that Mount Pinatubo had an impact upon that winter, impacting the jet stream, leading to a warm winter in places like Chicago, followed by a cool summer in 1992.

[CoastalWx]

I agree. I'm not yet ready to write off winter.

 

My concern is more the lack of a -NAO. The 50mb vortex really has been "bend don't break" and it continues to do so. 

[donsutherland1]

My concern is more the lack of a -NAO. The 50mb vortex really has been "bend don't break" and it continues to do so. 

I agree that this is a somewhat worrisome situation. It's been remarkably resilient and persistent so far.

[thunderbolt]

Don The only concern I have for this winter it seems like the MJO the European ensemble forecast has it going through 4 5 and 6and then hitting a brick wall before going into 7

[donsutherland1]

I was 11 years old that winter and can thus only vaguely remember it. I do remember a brief cold period in January of 1992 in Toronto and, from what I can see from the stats, February 1992 was quite cold in Ottawa. I've read that Mount Pinatubo had an impact upon that winter, impacting the jet stream, leading to a warm winter in places like Chicago, followed by a cool summer in 1992.

I was living in Montreal at the time. I don't recall there being any snowfalls of 20 cm or more. A number of storms saw the snow change over to sleet and freezing rain even in Quebec City where I spent some time. There was a pretty significant (at least for spring) snowfall just before mid-April.

[donsutherland1]

Don The only concern I have for this winter it seems like the MJO the European ensemble forecast has it going through 4 5 and 6and then hitting a brick wall before going into 7

This is also something that bears watching. Fortunately, longer-range MJO forecasts aren't always skillful.

[donsutherland1]

Just so there's no confusion, today's lengthy post does not mean that I have given up on winter. I have not thrown in the towel. Although, I think there's some possibility of a warm winter (especially if the AO goes strongly positive and blocking doesn't develop), it's too soon for me to believe that's the most likely outcome. I believe odds still favor a colder than normal January and February, though there will likely be some milder periods. Even the AO forecasts have been very volatile in recent days, so one shouldn't have high confidence in the current one.

 

In terms of the long-awaited pattern change, the 12z GFS still shows a colder pattern for December 28 through at least much of the first week in January.

[donsutherland1]

To further illustrate the uncertainty that lies ahead, notice how the CFSv2 has had numerous changes in its January outlook:

 

 

Given that uncertainty, there's really little reason for me to conclude that a 1991-92-type nightmare is the most likely scenario.