Has the NINA Peaked?

[BlizzardWx]

After looking at this for the past couple of weeks, I am willing to bet we're in that transition period near the peak... where we'll still have cooling at the surface because of upwelling... but the sub-surface, as a whole, starts gaining heat content. I could still see us squeaking out a strong tri-monthly peak... and then, the MEI suggests this is solidly a strong Nina, and the MEI is a better indicator of how the resulting pattern will actually behave. This seems like a 2007-2008 situation... where we have a borderline situation on the ONI... but we have the pattern in the heart of the winter act like the Nina was firmly in the strong range. I don't see any reasons, as of now, for folks' previous winter forecasts to change because of this.

You make a good point here. I don't think its anywhere close to falling apart by any means but I think its our first sign of its eventual weakening to see the subsurface starting to lose some of its steam. I guess I would say lets wait and see if it keeps warming or not before we get too excited about any outcome.

[nzucker]

If the TAO is correct, the La Niña saw some good cooling during the 12/5-12/10 period, and this doesn't even include Region 1.2 where a new bubble of -3C anomalies has surfaced/developed as that's well off the TAO plot:

12/5:

12/10 (new):

[Ji]

Nina is collapsing

[nzucker]

Not much change as per CPC Weeklies:

Region 1.2: -1.6C

Region 3: -1.6C

Region 3.4: -1.5C

Region 4: -1.4C

[skierinvermont]

The Nina warmed a bunch late last week... we barely going to make strong. CFS says 1.5/1.6. No where close to record

[skierinvermont]

Yeah, I'm real worried...Skier is one of those folks who never makes his own forecasts yet repeatedly criticizes others' forecasts. I honestly don't want to hear another peep from him until he comes out with a full set of forecasts and puts his reputation on the line as I have and many others have. He is basically a nuisance at this point and just finds numerous threads to troll me in. Clearly doesn't understand the point of these forums.

I made a guess of -1.7C-1.8C this summer and have stuck with that guess the entire event.

I don't think the point of these forums is for every know nothing weenie to make a forecast about every weather phenomenon on the planet. I will leave the forecasting to the experts. I suggest you do the same.

[nzucker]

I made a guess of -1.7C-1.8C this summer and have stuck with that guess the entire event.

I don't think the point of these forums is for every know nothing weenie to make a forecast about every weather phenomenon on the planet. I will leave the forecasting to the experts.

I said -1.8C to -2.0C so looks as if we were quite similar.

I am not a "know nothing weenie". My Winter 09-10 forecast was right on the money as were the analogs presented....my December 2010 forecast also came out pretty darn well. I had a better verification than HM, surely one of the experts, who said that December would look more like 1954 with widespread warm anomalies over the Midwest/Plains...I said 1955 with cold in these areas. Looks as if I did well. I think everyone on the forum should have a right to forecast and debate with the experts. Indeed, it seems as if amateur forecasts for Winter 10-11 (okie333, Isotherm, etc) have been doing better than many professional ones this winter because they relied more on experimental solar/blocking theories rather than tried-and-true ENSO formulas which have been a massive fail this winter. A lot of the meteorologists on this board also need to be challenged by amateurs as it forces them to look at different perspectives and explain their reasoning for everyone.

[JoMo]

It's the WEATHER folks...not something to flip out about.

Some people are very passionate about things, even weather. Sometimes you just have to agree to disagree.

[nzucker]

Great.. so when your forecast busts, you switch from using the ONI which we have been using this entire thread all year to the MEI. Good move.

I tell you what.. if you can find one meteorologist that says this event has the slightest chance of 'flirting with '73-74 I will wait until springtime.

HM actually told me back in November he thought we had a chance at the record, not sure that he'd agree now. But there's no reason not to wait...we'll just see where it goes as the winter progresses. Why do you need to prove that I've busted now? Why does showing me to have busted give you satisfaction when you don't even make forecasts yourself? What in your life is deficient that you have to rely on a weather forum for an ego boost? In any case, my winter forecast said -1.8C to -2.0C which is going to be close enough for an approximation of the ENSO event's impact on the global pattern. Not that these exact numbers mean anything anyway, since the regions are arbitrarily drawn and you can see that the impact of this event is super wide extending to like 15S or so with the belt of cold anomalies, much more so than what we saw in 07-08.

I thought we might get a similar ONI to 73-74...even if that doesn't happen, the effect on the global SSTs/SOI/MEI and Pacific pattern will be similar. Obviously we didn't have the blocking that year though for our winter weather.

[am19psu]

Will you two please knock it off.

[Isotherm]

I said -1.8C to -2.0C so looks as if we were quite similar.

I am not a "know nothing weenie". My Winter 09-10 forecast was right on the money as were the analogs presented....my December 2010 forecast also came out pretty darn well. I had a better verification than HM, surely one of the experts, who said that December would look more like 1954 with widespread warm anomalies over the Midwest/Plains...I said 1955 with cold in these areas. Looks as if I did well. I think everyone on the forum should have a right to forecast and debate with the experts. Indeed, it seems as if amateur forecasts for Winter 10-11 (okie333, Isotherm, etc) have been doing better than many professional ones this winter because they relied more on experimental solar/blocking theories rather than tried-and-true ENSO formulas which have been a massive fail this winter. A lot of the meteorologists on this board also need to be challenged by amateurs as it forces them to look at different perspectives and explain their reasoning for everyone.

Nate -- great post and I couldn't agree more.

[nzucker]

Nate -- great post and I couldn't agree more.

Thanks...and I don't mean to disrespect the great meteorologists on this board in any way. There's no doubt in my mind that HM, VAWXMAN, Usedtobe, etc. know 1000x more about meteorology than I and perhaps 100x more than you. But often amateurs looking at the pattern with an outsider's perspective, and without people to impress or earn a paycheck from, can come up with more accurate forecasts. At least on some occasions this is true, especially when we're in such an unprecedented regime that rewards gambling with experimental data like the connection between geomagnetic flux and the AO/NAO. Safer forecasts based on well-studied factors like La Niña and the +QBO/HT relationships are going down in flames, and mine will be one of them eventually.

The only people whose winter forecasts are doing well this time around are okie333 and you....I did great on December, dare I say better than many of the mets, but I'm in for an epic bust in January as this brutal cold drains down from the Arctic. I'm starting to wonder if we can stay cold in February, too, when I had most of the country very warm with only a small chunk of negative departures in the Pac NW and Northern Rockies. This is not the type of strong La Niña winter I'm accustomed to, basically a totally different beast from 07-08 or 99-00. Those who emphasized the older analogs like you, Harry, and I are definitely going to have a better verification this time around. Of course, we can have a riskier forecasting strategy since it doesn't pay the bills for us.

[Isotherm]

Thanks...and I don't mean to disrespect the great meteorologists on this board in any way. There's no doubt in my mind that HM, VAWXMAN, Usedtobe, etc. know 1000x more about meteorology than I and perhaps 100x more than you. But often amateurs looking at the pattern with an outsider's perspective, and without people to impress or earn a paycheck from, can come up with more accurate forecasts. At least on some occasions this is true, especially when we're in such an unprecedented regime that rewards gambling with experimental data like the connection between geomagnetic flux and the AO/NAO. Safer forecasts based on well-studied factors like La Niña and the +QBO/HT relationships are going down in flames, and mine will be one of them eventually.

The only people whose winter forecasts are doing well this time around are okie333 and you....I did great on December, dare I say better than many of the mets, but I'm in for an epic bust in January as this brutal cold drains down from the Arctic. I'm starting to wonder if we can stay cold in February, too, when I had most of the country very warm with only a small chunk of negative departures in the Pac NW and Northern Rockies. This is not the type of strong La Niña winter I'm accustomed to, basically a totally different beast from 07-08 or 99-00. Those who emphasized the older analogs like you, Harry, and I are definitely going to have a better verification this time around. Of course, we can have a riskier forecasting strategy since it doesn't pay the bills for us.

Thanks, and you make a good point re the forecasts. Many who are employed in the field probably had more pressure to be correct, thus they went w/ the safer/conservative route of heavily utilizing Nina climo.

This Nina has no signs of weakening at least for the next several weeks IMO. SOI daily values have been consistently high, and the monthly value for DEC of about +25 has been the greatest 30 day period yet of +SOI.

http://www.longpaddock.qld.gov.au/seasonalclimateoutlook/southernoscillationindex/soigraph/index.php

I wouldn't be surprised to see a weekly value as low as -2.0c. Trimonthly I still think we'll end up in the low end strong territory, -1.5c/-1.6c

But what's amazing w/ this winter is we've got the best of both worlds -- excellent cold air source via the strong la nina, and a very favorable arctic/atlantic pattern to deliver this bitter air southward into the CONUS. Last winter we had the phenomenal blocking but no true vodka cold, due in part to the strong el nino. But this time we have plenty of reserves up north. I'm worried my Jan forecast wasn't cold enough, like december.

[nzucker]

But what's amazing w/ this winter is we've got the best of both worlds -- excellent cold air source via the strong la nina, and a very favorable arctic/atlantic pattern to deliver this bitter air southward into the CONUS. Last winter we had the phenomenal blocking but no true vodka cold, due in part to the strong el nino. But this time we have plenty of reserves up north. I'm worried my Jan forecast wasn't cold enough, like december.

Yes, exactly, we're benefiting from the global cooling effect of the strong La Niña and the natural tendency for the PV to be stronger/colder....at the same time we're benefiting from the monster NAO/AO block that's sending all this vodka cold air south as Europe and central Siberia saw during December. I looked at the GFS 2m temperature anomaly map today, and it's pretty safe to say we're getting close to the long-term average regarding global temperatures; most of the map is covered in blue, especially the Southern Hemisphere, Antarctica, and Europe, with only a few areas of much above average temperatures remaining in the blocking regions of the Arctic. Plenty different from last winter when we had the NAO/AO in our favor but global temperatures were torching and the PV sat in Eurasia for the entire cold season.

I'm thinking this January may be one for the ages, Tom. We've got an active northern jet with a polar low modeled for this weekend and then a southern disturbance to track next week. After tomorrow, temperatures look exceedingly cold with 850s staying around -10C through most of the weekend. The ECM and GFS want to bring a monster PV into Canada due to the massive -EPO block, sending all the frigid air into the High Plains and Midwest. The 12z ECM had us at -15C 850s at Day 10 with much colder air moving down through the Great Lakes, near -30C temperatures. If we have a fresh snowpack on the ground and these airmasses over us, we'll be absolutely frigid. I am also excited because after the EPO dumps the cold, the NAO looks to revert back to its negative state setting up the possibilities for more storminess in the latter half of January. I keep wondering when the blocking pattern is going to break down but it just gets more intense. Truly amazing that both England and Florida had their coldest December in over 100 years. I'm starting to think the next few winters are going to be memorable and that great things lie ahead in terms of NH cold seasons.

[A-L-E-X]

Thanks...and I don't mean to disrespect the great meteorologists on this board in any way. There's no doubt in my mind that HM, VAWXMAN, Usedtobe, etc. know 1000x more about meteorology than I and perhaps 100x more than you. But often amateurs looking at the pattern with an outsider's perspective, and without people to impress or earn a paycheck from, can come up with more accurate forecasts. At least on some occasions this is true, especially when we're in such an unprecedented regime that rewards gambling with experimental data like the connection between geomagnetic flux and the AO/NAO. Safer forecasts based on well-studied factors like La Niña and the +QBO/HT relationships are going down in flames, and mine will be one of them eventually.

The only people whose winter forecasts are doing well this time around are okie333 and you....I did great on December, dare I say better than many of the mets, but I'm in for an epic bust in January as this brutal cold drains down from the Arctic. I'm starting to wonder if we can stay cold in February, too, when I had most of the country very warm with only a small chunk of negative departures in the Pac NW and Northern Rockies. This is not the type of strong La Niña winter I'm accustomed to, basically a totally different beast from 07-08 or 99-00. Those who emphasized the older analogs like you, Harry, and I are definitely going to have a better verification this time around. Of course, we can have a riskier forecasting strategy since it doesn't pay the bills for us.

I completely agree with you about challenging the "tried and not always true" methods (sorry, I had to amend that phrase because it often fails), because this is how you advance science. If we always stuck to narrowminded conventionality, science would become static and there would be no new innovations. I remember your riding the 1955-56 analog from the beginning of the season and I mentioned to you the fact that, hey, if youre going to factor in the solar influence, you also have to look at old analogs like 1916-17 and 1903-04 and 1909-10. I remember tacoman was also on that trail. Looks like things are working in our favor Regarding a January for the ages-- man, I wonder what a colder version of January 1996 would have been like (probably something like a combo of January 1994 and January 2004, a la nina acting like an el nino lol, but with more cold).... Isotherm described it really well when he said, the storminess seems to be a remnant of the el nino of last year, but the arctic cold is what the la nina is bringing to the table, with the solar influence being the main course

We could use a bit less arguing though-- by reading the last few pages, one wouldnt know that you and skier are supposedly really good friends.

[nzucker]

I completely agree with you about challenging the "tried and not always true" methods (sorry, I had to amend that phrase because it often fails), because this is how you advance science. If we always stuck to narrowminded conventionality, science would become static and there would be no new innovations. I remember your riding the 1955-56 analog from the beginning of the season and I mentioned to you the fact that, hey, if youre going to factor in the solar influence, you also have to look at old analogs like 1916-17 and 1903-04 and 1909-10. I remember tacoman was also on that trail. Looks like things are working in our favor Regarding a January for the ages-- man, I wonder what a colder version of January 1996 would have been like (probably something like a combo of January 1994 and January 2004, a la nina acting like an el nino lol, but with more storminess)....

We could use a bit less arguing though-- by reading the last few pages, one wouldnt know that you and skier are supposedly really good friends.

I wish I had adhered more to the great blocking patterns we saw in La Niñas 55-56 and 70-71 in my winter forecast, although even those years didn't have cold anomalies in the Southeast as this December did. I went cold for much of the nation in my winter forecast for December, but I had the Southeast at average expecting some ridging there. It turned out that the heart of the cold was aimed directly at the Southeast and Mid-Atlantic, with Florida having its coldest December on record and numerous snow events in North Carolina and Virginia. The 55-56 and 70-71 analogs would not have given this idea of a cold Southeast:

You can see that the heart of the cold was in the Northern Plains and Northern New England in 55-56 and 70-71, and it stayed that way for much of the rest of those winters with the South never really experiencing cold temperatures. I agree that the older analogs are very useful in this case (1903-04, 1909-10, 1916-17) but even they featured the north-south gradient with the heart of the cold remaining over the High Plains and only penetrating in modest form to the Southeast states. It's just so unusual to see a strong La Niña with the heart of the cold sitting over Florida and Georgia, and I don't think anyone could have predicted this. Here is what the Decembers of the older analogs looked like as a composite:

January is also going to throw many conventional Niña forecasts off because of how cold it is looking for the entire CONUS. January 1956 was basically a blowtorch; January 1971 was cold across the Northeast and Northern Plains but didn't have any cold departures over the Southeast and Mountain West, as I'm expecting this month. January 1904 was cold in the Northeast/Ohio Valley but saw positive temperature departures in Montana and much of the Pacific Northwest. January 1910 was warm except for the West Coast. January 1917 had a monster SE ridge. None of these analogs really fit what we may see this month; it's just so unusual to have a La Niña pattern work out this way, but it's a great learning experience for all of us who are interested in weather.

By the way, here is what December 2010 looked like in temperature anomalies:

[tacoman25]

January is also going to throw many conventional Niña forecasts off because of how cold it is looking for the entire CONUS. January 1956 was basically a blowtorch; January 1971 was cold across the Northeast and Northern Plains but didn't have any cold departures over the Southeast and Mountain West, as I'm expecting this month. January 1904 was cold in the Northeast/Ohio Valley but saw positive temperature departures in Montana and much of the Pacific Northwest. January 1910 was warm except for the West Coast. January 1917 had a monster SE ridge. None of these analogs really fit what we may see this month; it's just so unusual to have a La Niña pattern work out this way, but it's a great learning experience for all of us who are interested in weather.

By the way, here is what December 2010 looked like in temperature anomalies:

If you roll forward the closest Nina matches to this Dec (1917, 1942, 1950, 1955, 1962, and 1995), this is what January looked like.

Given the ongoing patterns and the big -EPO ridge that appears to be coming, I'd say we have a good shot to have the coldest January for the CONUS since at least 1985.

[A-L-E-X]

Tacoman, that 1942-43 analog is another good one, which I also remember Don S mentioning. WW1 and WW2 winters had severe cold in north america and western europe, something which also seems to be happening this winter.

[HM]

I said -1.8C to -2.0C so looks as if we were quite similar.

I am not a "know nothing weenie". My Winter 09-10 forecast was right on the money as were the analogs presented....my December 2010 forecast also came out pretty darn well. I had a better verification than HM, surely one of the experts, who said that December would look more like 1954 with widespread warm anomalies over the Midwest/Plains...I said 1955 with cold in these areas. Looks as if I did well. I think everyone on the forum should have a right to forecast and debate with the experts. Indeed, it seems as if amateur forecasts for Winter 10-11 (okie333, Isotherm, etc) have been doing better than many professional ones this winter because they relied more on experimental solar/blocking theories rather than tried-and-true ENSO formulas which have been a massive fail this winter. A lot of the meteorologists on this board also need to be challenged by amateurs as it forces them to look at different perspectives and explain their reasoning for everyone.

Well, I agree you are not some weenie, but let's be careful here on what you are saying about the "experts". I know for a fact other "experts" use solar parameters to forecast, including myself. In fact, it is what kept me from going warm in the East for December. In my defense, you didn't see my maps either but I did became increasingly colder from 1954. While 1955 was closer than 1954, I don't think anyone/any analog was all that good unless they put their strongest anomalies in the Southeast, where some folks got their coldest December ever. The citrus crops took a beating here, especially with the extreme oscillating temperatures and the fact the cold was early in the season. In a business sense, that may have mattered more than how strong you made your western ridge.

I also don't agree that meteorologists are bogged down by the fact that they are receiving a pay check. The pay check just makes sure you look over everything several times and produce a responsible forecast. I can just as easily turn your post around and suggest why some of these forecasts on the forum were irresponsible. There was something wrong with everyone's December forecast, one way or another. So let's just be happy with that and move on...

[JamieOber]

Well, I agree you are not some weenie, but let's be careful here on what you are saying about the "experts". I know for a fact other "experts" use solar parameters to forecast, including myself. In fact, it is what kept me from going warm in the East for December. In my defense, you didn't see my maps either but I did became increasingly colder from 1954. While 1955 was closer than 1954, I don't think anyone/any analog was all that good unless they put their strongest anomalies in the Southeast, where some folks got their coldest December ever. The citrus crops took a beating here, especially with the extreme oscillating temperatures and the fact the cold was early in the season. In a business sense, that may have mattered more than how strong you made your western ridge.

I also don't agree that meteorologists are bogged down by the fact that they are receiving a pay check. The pay check just makes sure you look over everything several times and produce a responsible forecast. I can just as easily turn your post around and suggest why some of these forecasts on the forum were irresponsible. There was something wrong with everyone's December forecast, one way or another. So let's just be happy with that and move on...

Yeah, that whole thing about a paycheck hurting forecasts made zero sense. As much as I enjoy nzucker's posts that demonstrates nothing but lack of knowledge on how the private sector works. If you blow it over and over again like a lot of amateurs here do a lot, no big deal. If you do that as a professional, you are out of a job.

[nzucker]

Well, I agree you are not some weenie, but let's be careful here on what you are saying about the "experts". I know for a fact other "experts" use solar parameters to forecast, including myself. In fact, it is what kept me from going warm in the East for December. In my defense, you didn't see my maps either but I did became increasingly colder from 1954. While 1955 was closer than 1954, I don't think anyone/any analog was all that good unless they put their strongest anomalies in the Southeast, where some folks got their coldest December ever. The citrus crops took a beating here, especially with the extreme oscillating temperatures and the fact the cold was early in the season. In a business sense, that may have mattered more than how strong you made your western ridge.

I also don't agree that meteorologists are bogged down by the fact that they are receiving a pay check. The pay check just makes sure you look over everything several times and produce a responsible forecast. I can just as easily turn your post around and suggest why some of these forecasts on the forum were irresponsible. There was something wrong with everyone's December forecast, one way or another. So let's just be happy with that and move on...

Yes, you made an awesome call about the Southeast, HM, way better than mine. I had the Southeast average for the month with cold departures limited to the Mid-Atlantic, Northeast, Midwest, and Northern Plains states. I'm glad I leaned a little colder in the areas you saw warming up, but as you say, one of the most important parts of the forecast was getting the Southeast right due to the immense crops affected there (unfortunately). I agree that none of the analog years mentioned, including older analogs, had the right temperature distribution with the heart of the cold in the SE; that's just entirely strange for a La Niña and still puzzles me. I mean we've seen Niña years that had a -NAO like 70-71 but weren't cold in the SE; they still had the north/south temperature gradient but just pushed a bit further south with the below average due to the blocking. So what made this one different? Was it just the utter strength of the AO/NAO? GoA low a bit further west causing more of a neutral/positive PNA at times to push the cold further south?

As you say, the anomalies were a bit like an El Niño but not entirely...the Northern Plains would normally be warmer in an El Niño, I'd think, especially a strong one. Of course that depends on the AO too as we saw last year when I busted warm in the Northern Plains going with the Niño climo. A weak Niño could be colder up there too.

I didn't mean any offense about the paycheck, but I just know I'd be more hesitant to go against ENSO climo too much if I were making a professional forecast in a very strong La Niña year. I'd be uncomfortable relying on the "new stuff' like solar minimum compared to the traditional methods of ENSO, PDO, etc...that's all I meant. It would be risky to put record cold in the Southeast and huge warm anomalies in the West/NW with a strong Niña and -PDO. I guess you did this to some extent but maybe didn't lean quite as cold as you could have for the Midwest/High Plains.

It would be nice if you reposted your 10-11 winter forecast. I am not sure I trust self-verification scores from somebody who was mocking my low end strong Nina call and still declaring we would 'flirt with '73-74' at the end of December. Perhaps you should do what Chuck does an allow other people to grade your forecasts.

Winter Forecast2010-11

Winter 09-10 was the 18^th coldest on record forthe continental United States, and it was an historic season formany with record-breaking snowfall in the Mid-Atlantic related to a series ofpotent Nor’easters and unprecedented high-latitude blocking. Although ENSO hasdone a 180-degree reversal with the development of a strong La Niña during thesummer, many of the same players that drove the historic pattern last winterremain on the playing field. These factors, which include the current –PDOdecadal regime, a consistent –NAO/-AO, and low solar activity, will also have amajor influence on Winter 10-11, although they will be manifested differentlyagainst the backdrop of a strong La Niña.

The latest CPC ENSO update, released on October 12^th,shows that SST anomalies in the equatorial Pacific are consistent with the ideaof a strong La Niña being the main regime driver for Winter 10-11. Region 4 isat -1.4C, Region 3.4 is at -1.8C, Region 3 is at -1.7C, and Region 1.2 is at-2.1C. Although daily reports show that recent warming has reduced theseanomalies somewhat, the University of Albany u-wind anomaly forecast haspowerful trade winds from 140-180W that will dominate between October 16^thand October 23^rd, resuming the cooling. Given a pool of -5Csubsurface anomalies and the projected resumption in trade winds, I predict anONI peak between -1.8C and 2.0C.

A potent cold tongue has been slowly inching west, withRegion 4 having its coldest SST anomalies since Fall 1975. Given thecirculation of the Hadley Cell and the power of the western ENSO regions todrive the Northern Hemisphere 500mb pattern (as we saw in the opposite way lastyear), the forecasted set-up for this cold season is an Aleutian High/Gulf of Alaska Lowconfiguration. Although this La Niña is not nearly as west-based as 1998-99,the pattern will be warmer nationally than an east-based Niña like 1970-71. Thenegative PDO decadal cycle and colder waters surfacing in the Gulf of Alaska should reinforce these tendencies. The +EPO will becomeincreasingly dominant later in the winter as the Niña matures and the –QBOremnants fade, meaning that the temperature gradient will change fromnorth/south early in the winter to west-east later in the cold season,consistent with many of my preferred analogs.

High-latitude blocking will be a key element of the 2010-11Winter, although not nearly to the extent of last season. With the expectedcold tongue in the western ENSO regions driving a dominant Gulf of Alaska lowand a 500mb polar vortex over Alaska,as has been the pattern in most La Niña analogs, the majority of blocking willcome from the Atlantic side. In the past two years, the NAO has spentapproximately three months in positive territory; this pattern will continuethroughout the winter with a favorable Atlantic SST configuration (Newfoundlandcold pool, warm waters near Greenland), a lingering –QBO tendency leading to apotential stratospheric warming event in late November, and Eurasian snow coverexpected to be higher than normal. Low solar activity, coupled with occasionalflares as Cycle 24 ramps up, should be enough to disturb occasionally a polarvortex that is expected to be strong due to the colder stratosphere. Blockingwill be strong early in the winter, from mid-December through early January,fade for the heart of the winter, and then return with a vengeance in March asthe La Niña wanes and we see the hints of a –EPO/+PNA regime.

So what does all this mean in terms of sensible weather? I’mexpecting Winter 10-11 to be generally a reverse of last season in terms of whogets pummeled with cold and snow and who stays high and dry. The Mid-Atlanticand Southeast will see much drier and warmer conditions this winter, especiallylater in the season as a SE ridge takes control of the pattern with the–PNA/+EPO being dominant. December and early March will be the periods to watchfor a surprise snowstorm at the lower latitudes of the East, although CADregions will have to keep a close eye on icing threats throughout the seasongiven the colder air across Canadaand northern stream activity expected in a La Niña season.

Confidence is high in warmer than normal temperatures acrossthe Southern Plains, the Southeast and the mid-Atlantic, with below averagesnowfall in these areas. With the –PNA becoming ahallmark of the season later on, confidence is also high in below averagetemperatures and above average snowfall for the Northern Rockies and PacificNorthwest, as well as Northern California.Confidence is lower further north along the East Coast; I expect temperaturesand snowfall to be near average for New England, with a somewhat mild winterwith less snowfall towards New York City and Philadelphia. As they didin the La Niña winters of 07-08 and 08-09, I expect the Great Lakes to have an active season with above average snowfalls and temperaturesnear average. Given warm lake surface temperatures, this should be an excellentseason for lake effect snow. Confidence is also low for the Northern Plains,which are cold in many La Niña analogs; however, early indications are that a+EPO may prevent arctic airmasses from penetrating into Canada, so I expectthese regions to be near average with above average snowfall from lakescutters. Confidence is also low for the Southwest, where deep troughs in lateJanuary and February may mitigate the warmth caused by an inactive sub-tropicaljet. We’ve already seen several cut-off lows from the northern stream off the California Coast this season, so that tendency willhave to be watched.

Maps:

December:

January:

February:

March:

Snowfall:

[skierinvermont]

Average. Pretty good in the northeast and midwest. Far too warm in the Mid-Atlantic, OH valley, SE and gulf coast. Too cool in the west. B-/C+.

Not trolling you here.. just giving an honest opinion.

[tacoman25]

Average. Pretty good in the northeast and midwest. Far too warm in the Mid-Atlantic, OH valley, SE and gulf coast. Too cool in the west. B-/C+.

Not trolling you here.. just giving an honest opinion.

Grading on a curve though, his forecast was definitely above average for December. He had the warmest anomalies in the SW, something correct you didn't point out. I'd give him a solid B.

[usedtobe]

Thanks, and you make a good point re the forecasts. Many who are employed in the field probably had more pressure to be correct, thus they went w/ the safer/conservative route of heavily utilizing Nina climo.

This Nina has no signs of weakening at least for the next several weeks IMO. SOI daily values have been consistently high, and the monthly value for DEC of about +25 has been the greatest 30 day period yet of +SOI.

http://www.longpaddo...graph/index.php

I wouldn't be surprised to see a weekly value as low as -2.0c. Trimonthly I still think we'll end up in the low end strong territory, -1.5c/-1.6c

But what's amazing w/ this winter is we've got the best of both worlds -- excellent cold air source via the strong la nina, and a very favorable arctic/atlantic pattern to deliver this bitter air southward into the CONUS. Last winter we had the phenomenal blocking but no true vodka cold, due in part to the strong el nino. But this time we have plenty of reserves up north. I'm worried my Jan forecast wasn't cold enough, like december.

Your ideas how important the blocking was certainly were better than mine. I did like a cold December but thought Jan would start modifying and be a little above normal and that Fen would be the warmest month relative to normal in the DC area. I liked Zwyts Capital Weather Gang forecast but with less snow for DC than he was calling for. Clearly, the blocking and AO are dominating the pattern even more than usually occurs with a nina and a negative AO. But then again, though I like to argue and toy with long range thoughts, I'm no long range guy. This year, day 3 forecasts have been hard enough to fathom. Anyway, both you and Okie have done a good job so far this winter.

Wes

[JamieOber]

Average. Pretty good in the northeast and midwest. Far too warm in the Mid-Atlantic, OH valley, SE and gulf coast. Too cool in the west. B-/C+.

Not trolling you here.. just giving an honest opinion.

Grading on a curve though, his forecast was definitely above average for December. He had the warmest anomalies in the SW, something correct you didn't point out. I'd give him a solid B.

Yeah...this year you have to grade on a curve given how crazy it has been.

I know extreme blocking can occur in late Feb in a Nina.....wonder if that will happen again this year even if Feb turns warm.

[uncle W]

the La nina January's following December's with well below average temperatures and the following months...

[nzucker]

Grading on a curve though, his forecast was definitely above average for December. He had the warmest anomalies in the SW, something correct you didn't point out. I'd give him a solid B.

I would give myself a B as well...I did poorly with the cold in the Deep South but very well with the Northeast/Northern Plains and Desert Southwest. I could have gone warmer for the entire West, but my forecast definitely hinted at some ridging developing there. I also said that the Mid-Atlantic would have a decent chance at a December snowstorm, and they got it along with many others on December 26th, with 14" falling at ORF and 12" falling at PHL. This was a tremendously difficult forecast so I'm pretty satisfied with the way it turned out. I'm not surprised Skier only gave me a C+/B-, though, as he tends to be a bit harsh on me as you might have noticed.

I am a bit worried about January, I wish I'd gone colder. Didn't think we'd have a strong -EPO pattern, but that looks to be happening. I like the cold anomalies I put out West but think I went too warm in the East/Mid-Atlantic. I do think we might see the SE ridge try to assert itself later in the month but the damage may be done at that point in terms of cold departures.

[tacoman25]

I would give myself a B as well...I did poorly with the cold in the Deep South but very well with the Northeast/Northern Plains and Desert Southwest. I could have gone warmer for the entire West, but my forecast definitely hinted at some ridging developing there. I also said that the Mid-Atlantic would have a decent chance at a December snowstorm, and they got it along with many others on December 26th, with 14" falling at ORF and 12" falling at PHL. This was a tremendously difficult forecast so I'm pretty satisfied with the way it turned out. I'm not surprised Skier only gave me a C+/B-, though, as he tends to be a bit harsh on me as you might have noticed.

I am a bit worried about January, I wish I'd gone colder. Didn't think we'd have a strong -EPO pattern, but that looks to be happening. I like the cold anomalies I put out West but think I went too warm in the East/Mid-Atlantic. I do think we might see the SE ridge try to assert itself later in the month but the damage may be done at that point in terms of cold departures.

You are definitely going to be too warm overall for January. But just about everyone will be.

[VAwxman]

Yeah, that whole thing about a paycheck hurting forecasts made zero sense. As much as I enjoy nzucker's posts that demonstrates nothing but lack of knowledge on how the private sector works. If you blow it over and over again like a lot of amateurs here do a lot, no big deal. If you do that as a professional, you are out of a job.

I think what he meant is that when it's your job, you do have to be careful going out on limbs too much, or making very risky calls, since most of the time those don't work (not to pick on JB here, but he gets in trouble a lot by going for the extreme too much). But definitely the name of the game is get it right as often as you can or you'll be out of work.

[MN Transplant]

I don't know if anyone has update the stats and charts for a while.

*The latest tri-monthly came in at -1.4, making this an "official" La Nina. 1988 was the last time there was an OND reading that low.

*BOM released their latest update today:

A major La Niña event continues to affect the Pacific Basin. Long-range forecast models surveyed by the Bureau suggest that the La Niña is likely to persist into the southern hemisphere autumn. All climate indicators of ENSO remain beyond La Niña thresholds. The tropical Pacific Ocean remains much cooler than average for this time of year, with temperatures below the surface up to 4 °C below normal in central and eastern parts (comparable to the La Niña event of 1988). Trade winds are stronger than average, while cloud patterns continue to show a typical La Niña signature with suppressed cloudiness in tropical areas near the dateline. The Southern Oscillation Index (SOI) value for December of +27 is the highest December SOI value on record, as well as being the highest value for any month since November 1973.

*The latest weekly 3.4 reading is -1.5, up from the two month low of -1.7 the previous week.

*The subsurface is still chilly