Winter 2011-2012

[Snowstorms]

Comparing 1995 and 2011 below;

Now it should become painfully clear that 1995 was a first year Nina that followed an onset of 3-4 El Nino’s prior to that year and 2011 is looking to become a second year La Nina following one of the strongest Nina’s on record based on the MEI. These differences are noteworthy and we can’t ignore these simple facts whereas some others just want a certain “repeat” of a certain “winter” either because if offered continuous storms or if it offered tremendous cold outbreaks or both.

Looking at the basics lets first observe the Jet streams. We know an El Nino tends to weaken the Polar Jet and in return it strengthens the Subtropical Jet. The subtropical jet is essential for storm development. A stronger STJ means more consistent storminess and more stronger/well developed storms but a Polar Jet is essential for continuous cold outbreaks and more below normal temperature anomalies. This is why La Nina Winters are often colder than El Nino’s and they offer stronger Arctic Outbreaks than Nino’s. Now we know the 1991-1995 El Nino regime which the La Nina of 1995-96 followed. The atmosphere despite being in a Nina state may have ahead an El Nino like persistence still left meaning the STJ may have been stronger than usual than a typical La Nina.

The STJ forms around the Hadley cell across the tropical regions across the Troposphere and we all know the Coriolis Effect, which shifts the Hadley Cell Eastward or left since it falls into the Southern Hemisphere and right in the NH. Because of this in El Nino’s the STJ is placed further north than usual and it this allows for more stronger storms to from across the Gulf and push northward in the Winter and this resulting wind change or Wind Shear in the Atlantic weakens storms and increases storminess across the Tropical Pacific.

The residual effect of the STJ may have still been in place in 1995-96 which contributed to a near record breaking winter season for much of the East Coast due to displaced Polar Jet and active STJ which is not typical for a La Nina.

Looking at long term trends we focus now on the PDO and AMO. The PDO was in its positive phase at the time and clearly the effects of a Warm PDO and Cold PDO are very different. On the other hand in 2011 the PDO is deeply negative and has been in its negative phase since 2007. During El Nino’s we have a Weaker Aleutian Ridge and during a La Nina we have a stronger Aleutian Ridge as a result of the PDO. In some cases we can see a blocking pattern develop over the Pacific than the Arctic itself but this can only be present in a La Nina or La Nada like 1989 when the blocking was centered across the Pacific for Nov/Dec 1989 but once those two months were over the blocking weakened allowing the warmth that was suppressed to move northward for Jan/Feb/Mar as a result of the SE Ridge. We did not see a SE Ridge in 1995-96 btw. The AMO had also transitioned to positive that year and the residual effect of the –AMO may still have been in place whereas this year it’s a +AMO.

Let’s observe the Height anomalies for Jun-Aug 1995 and compare them with this year.

1995

2011

Looking at similarities first we see a –AAO dominate both years across Antarctica. We see that the SOI is much more positive this year than 1995, we see the Aleutian High dominant this year and we don’t see it in 1995, with much of Western North American below normal in terms of Temperatures which is typical for a La Nina and instead we saw HP anomaly across Western Europe in 1995 whereas this year its been a LP anomaly. These are major differences and we see much of the Earth looks like a La Nina in 2011 than 1995.

The QBO however transitioned to negative later that year and remained negative for most of 1996 at 30 hpa. During a –QBO in a La Nina we often see the Aleutian High suppressed further South across the Central Pacific which is correlated well with a –PDO and this suppression allows the ridge to become stronger across the East allowing for a SE Ridge to be well developed and dominant. If at the same time the NAO/AO are negative we develop a very strong temperature gradient between the two air masses thanks to the strengthened Polar Jet allowing for more snow to fall and more severe outbreaks.

Looking at the Heights from 1995-96 we get this;

As you can see the atmosphere itself was not in a –QBO state with the Aleutian High centered much further north and West than a typical –QBO/-ENSO/-PDO configuration. Now comparing to 2008 we get this;

Notice the atmosphere was well established to a typical –ENSO/-PDO/-QBO pattern and notice the SE Ridge as a result of the Strong Aleutian High in the Pacific.

So in conclusion I personally don’t think 1995-1996 is a very good analogue to use.

Questions and comments will be appericated.

http://weatherintoronto.blogspot.com/2011/09/1995-and-2011-comparsion.html

[ORH_wxman]

So in conclusion I personally don’t think 1995-1996 is a very good analogue to use.

I agree. Don't think '07-'08 is very good either though. Also a first year Nina and likely much more potent than this one will be. Also no Atlantic blocking whatsoever that winter which I do not think will be the case this winter. I'd take '07-'08 again if you offered it to me right now, but its unlikely we play it out like that winter.

[Snowstorms]

I agree. Don't think '07-'08 is very good either though. Also a first year Nina and likely much more potent than this one will be. Also no Atlantic blocking whatsoever that winter which I do not think will be the case this winter. I'd take '07-'08 again if you offered it to me right now, but its unlikely we play it out like that winter.

Not implying to a repeat of 2007-08 even though I would love a repeat, lol but I'm just using it as an example to imply my -QBO/-ENSO/-PDO theory. There's the chance of a -AMO developing next year so that should be interesting. I personally think this year's Nina maybe more potent than last year offering more storminess and more cold outbreaks like the second year Nina back in 1917-1918.

The JMA develops a -AMO in the Atlantic come February/March 2012.

http://www.jamstec.go.jp/frsgc/research/d1/iod/

[CoastalWx]

Euro SIP models (which is an ensemble of models I believe) shows it trying to bottom out near -1C.

Trend has defintely been on the downside as of the last few months.

[Bob Chill]

We got some good replies from Wes after we moved it. But a lot of the good stuff that was already going to be said was said before we moved it. It was good to move it.

Plus we have a rep to keep in here of being the crappiest subforum on the site, so we can't have good discussion threads staying in here. Might ruin it.

There seems to be a correlation between the amount of posters in a sub-forum and the so called "quality" of the subforum. I for one have no problems with any forum or any poster and I think the SNE is fine. Certainly doesn't deserve the "crappiest" rep. It's just busy and can be hard sometimes during events to pull out the meaningful posts. Weenies like me are always looking for the detailed posts from the Mets and the quality non-met posters. I like the trend of separating analysis from banter. That works pretty well at times. Even when someone posts crap analysis in the analysis thread, the counter posting that ensues clears it up pretty good.

I don't have the knowledge to post in the pinned threads in the main forum so I stay out of them. However, I'm not weather dummy either and I do like to do armchair research and analysis. I will pop in here from time to time and post my thoughts and questions. The MA forum won't heat up for another month or so.

Anyway, here is something I have been looking at:

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml

89-90 and 99-00 have similar enso patterns to what we are seeing now. It looks like we will see enough cooling over the next couple months to put us in solid Nina territory. I know you can't hang a prediction based on ENSO alone because there is so much more in play. I'm focusing on December right now. Using a handful of second year Nina analogs and adding in some -AO summer analogs points towards are pretty cold December up and down the EC so Dec looks pretty good for folks down S in my area.

I'm expecting some warmth in Jan-Feb so I don't have high hopes for the whole winter and HM's post is just excellent at the potential mechanics in play this winter. I think you guys up here are looking good for Mar. Most of the composite anamoly plots I did showed near to slightly below normal Mar temps and + QPF. Unfortunately for my area, near normal Mar temps and + QPF means rain. lol

[40/70 Benchmark]

Euro SIP models (which is en ensemble or models I believe) shows it trying to bottom out near -1C.

Trend has defintely been on the downside as of the last few months.

I would def. take -1C and run with it...sign me up.

Snowstorms, you have had some solid contributions....nice addition to the forum.

[CoastalWx]

I would def. take -1C and run with it...sign me up.

Snowstorms, you have had some solid contributions....nice addition to the forum.

Yeah it would be nice to keep it at that level and agree with your comment on Snowstorms. He's had some nice stuff to post. Afterall, we need all the help we can get in the crappiest subforum on the board.

[ORH_wxman]

Euro SIP models (which is en ensemble or models I believe) shows it trying to bottom out near -1C.

Trend has defintely been on the downside as of the last few months.

That model has been trending down for 2-3 months now. I def think this has a shot to go moderate. I'd still guess borderline moderate or high end weak Nina at this point though.

[CoastalWx]

That model has been trending down for 2-3 months now. I def think this has a shot to go moderate. I'd still guess borderline moderate or high end weak Nina at this point though.

Seems like the evidence is building for perhaps a low end moderate maybe?

[Ginx snewx]

I would def. take -1C and run with it...sign me up.

Snowstorms, you have had some solid contributions....nice addition to the forum.

Agree and best avatar in the forum.

[weathafella]

I'm tending to have some big ticket analogs with the strongest weight to 2008-09 (60% but solidly 25% to) 1993-94.

So if I had to throw some numbers out I'd say widespread 150%+ on climo. For me that's 65+, for Ray that's 90+. Not ready to throw down the gauntlet and bet yet but getting closer.

Funny thing happened tonight. I saw what I thought was the fattest squirrel in history and began having fantasies of 300% snow year. Then I realized it was a frreaking racoon.

[HoarfrostHubb]

When you say 150, people (and squirrels) listen...

[HoarfrostHubb]

114" would rock

[weathafella]

i wish 1999-00 didn't have so many similarities. Thankfully there are enough differences also. Remember though, we saw some very cold air that winter albeit only for winter's 4 week duration.

[nzucker]

i wish 1999-00 didn't have so many similarities. Thankfully there are enough differences also. Remember though, we saw some very cold air that winter albeit only for winter's 4 week duration.

I don't think global SSTs are that similar; the Niña was stronger in 99-00, and the warmer waters were displaced further southwest in theNorth Pacific. That made it easier for a vortex to settle into AK.

I also think the Atlantic pattern was totally different from this era in 99-00; I doubt we could see an NAO this positive:

[weathafella]

I don't think global SSTs are that similar; the Niña was stronger in 99-00, and the warmer waters were displaced further southwest in theNorth Pacific. That made it easier for a vortex to settle into AK.

I also think the Atlantic pattern was totally different from this era in 99-00; I doubt we could see an NAO this positive:

Yeah you're pointing out the differences. But we did get that 3 week UK block that brought some amazingly cold wx in. Overall a dud of a winter and agree, Nina much stronger. 2000-01 may be a better match. 2008-09 is a great analog and we should have a better NAO this winter.

[CoastalWx]

Yeah you're pointing out the differences. But we did get that 3 week UK block that brought some amazingly cold wx in. Overall a dud of a winter and agree, Nina much stronger. 2000-01 may be a better match. 2008-09 is a great analog and we should have a better NAO this winter.

It's been the late winter months that have fooked us from an all out epic year, as of late.

[weathafella]

Yeah you're pointing out the differences. But we did get that 3 week UK block that brought some amazingly cold wx in. Overall a dud of a winter and agree, Nina much stronger. 2000-01 may be a better match. 2008-09 is a great analog and we should have a better NAO this winter.

Also, solar is different and that's probably a bigger factor in the more robust snow winters over the past 5 years than people realize.

[HIPPYVALLEY]

It's been the late winter months that have fooked us from an all out epic year, as of late.

The past 3 Marches have not been kind to W. Ma.

[weathafella]

It's been the late winter months that have fooked us from an all out epic year, as of late.

Yeah. I bet we go too much in one direction and the proverbial rubber band breaks. Last January was so epic you had to see it coming but none of us wanted to...

[CoastalWx]

The past 3 Marches have not been kind to W. Ma.

I hate seeing winter fade in February. 6 weeks of ballz to the wall, then a violent decrease in activity in the final 8 weeks or so. I'd sacrifice some snowpack if I could have some storms in March. Yeah I know snow doesn't like to hang around too much in March, but it provides some excitement instead of 45F sunny days.

[nzucker]

Also, solar is different and that's probably a bigger factor in the more robust snow winters over the past 5 years than people realize.

The solar minimum has no doubt affected the NAO; the Maunder Minimum also had a very negative NAO, and that was when the index was first observed, I believe by Danish and Scandinavian explorers who noted the cold weather in Europe and the mild conditions for seal and whale hunting near Greenland when they made their long maritime voyages in the North Atlantic during that blocking pattern. It seems that the arctic indices (NAM) tend to become stuck in their negative phases when we see lower solar activity, despite a colder stratosphere. For example, we had a cold stratosphere in 10-11 very much like the 1950-51 winter, and yet the NAO blocking was completely different being deep in the solar minimum.

Having low solar activity combined with a -QBO increases the chance for a SSW and a -NAO. The biggest problem in my mind is the potential for a displaced Aleutian ridge with the PAC side favoring a colder West/Northern Plains and a warmer east with the PV located more over AK/Western Canada, and occasionally retreating to Siberia as the +EPO develops later in the winter.

[CoastalWx]

Yeah. I bet we go too much in one direction and the proverbial rubber band breaks. Last January was so epic you had to see it coming but none of us wanted to...

Nina is a b*tch sometimes. That seems to be its mantra where the first two months are cold, and then it finally flexes its muscle.

[weathafella]

2008-09 is an excellent analog....doesn't get much better. 2nd year Nina, similar QBO/PDO/ prior summer. The difference is we are more solidly into the NAO now which could make it even better. Nate's concerns are correct imho and that's what could kibosh the forecasts. If we're lucky, PDO relaxes just enough to help us get the ridge where we went it in the NPAC.

[HIPPYVALLEY]

I hate seeing winter fade in February. 6 weeks of ballz to the wall, then a violent decrease in activity in the final 8 weeks or so. I'd sacrifice some snowpack if I could have some storms in March. Yeah I know snow doesn't like to hang around too much in March, but it provides some excitement instead of 45F sunny days.

Could not agree more. I'd gladly take a slow start to winter if we could have the 8 weeks from mid January to mid March be epic.

[CoastalWx]

Could not agree more. I'd gladly take a slow start to winter if we could have the 8 weeks from mid January to mid March be epic.

The snowpack people might argue with me, but I'm not used to prolonged stretches of deep snow anyways. March is useless to me if it's 45 and sunny. I'd rather stretch it out with 3-4 snow threats. Same deal with February, as that month has now been lackluster too. Last year wasn't bad from a statistic standpoint, but for all intents and purposes...we spent the month watching the snow melt.

[HoarfrostHubb]

The snowpack people might argue with me, but I'm not used to prolonged stretches of deep snow anyways. March is useless to me if it's 45 and sunny. I'd rather stretch it out with 3-4 snow threats. Same deal with February, as that month has now been lackluster too. Last year wasn't bad from a statistic standpoint, but for all intents and purposes...we spent the month watching the snow melt.

Yeah... that sucks...April is boring, too

[CoastalWx]

That storm at least put a nice ending to the winter. Hell, you finally beat me Dave..lol.

[HoarfrostHubb]

Could not agree more. I'd gladly take a slow start to winter if we could have the 8 weeks from mid January to mid March be epic.

You need some elevation for your desperation

[HoarfrostHubb]

That storm at least put a nice ending to the winter. Hell, you finally beat me Dave..lol.

Seriously, when was the last time Boston got a sizable March event? (4"+)