SE Mid-Long Range Discussion

[burgertime]

http://www.americanw...ost__p__1174358

Don pretty much drove a stake through the heart of the rest of this month.

Maybe next month as well. It should be interesting to see how it all unfolds. That graphic you posted of the AO is just killer.

[dsaur]

That 00gfs system on the 16th is the kind of pattern change I want to see. It'd be great if it works further south ...then the next few would have a new path to trod, and the closed low in the Baha at the end would give me my guess the big storm win T

[Carvers Gap]

Been watching the AO for days, even posted about Don's comments on the +AO a few days ago. His comments yesterday should send a chill down the spine of every winter lover in the East. Now, one thing for sure, NE TN snowfall is not always connected to how much it snows in the big cities. In the 70s many storms would slam the southern Apps and leave the I-95 cities w/ rain or pass completely south of them. But overall, I think his comments that no KU storms will happen this year might come to pass, but is by no means a certainty. If anything, the atmosphere seems primed to do so at some point this month as many have alluded to the potential for a big storm w/ these cut-offs. And I'll say this, when Don speaks I listen. He has an outstanding knowledge base about the AO and NAO. It seems this winter will have to beat the odds, much like last winter, if we are to get an extended period of winter weather. And hey, if we get cold weather in January I'm not complaining. It's by far our best chance climo speaking. What will be interesting will be the correlation(or lack thereof) w/ the -PDO and/or interaction w/ the -PDO. If this winter turns out being cold against seemingly growing odds, I do think it's good evidence that the game has changed. But certainly, it's looking like a warm winter is ahead.

[Cold Rain]

Been watching the AO for days, even posted about Don's comments on the +AO a few days ago. His comments yesterday should send a chill down the spine of every winter lover in the East. Now, one thing for sure, NE TN snowfall is not always connected to how much it snows in the big cities. In the 70s many storms would slam the southern Apps and leave the I-95 cities w/ rain or pass completely south of them. But overall, I think his comments that no KU storms will happen this year might come to pass, but is by no means a certainty. If anything, the atmosphere seems primed to do so at some point this month as many have alluded to the potential for a big storm w/ these cut-offs. And I'll say this, when Don speaks I listen. He has an outstanding knowledge base about the AO and NAO. It seems this winter will have to beat the odds, much like last winter, if we are to get an extended period of winter weather. And hey, if we get cold weather in January I'm not complaining. It's by far our best chance climo speaking. What will be interesting will be the correlation(or lack thereof) w/ the -PDO and/or interaction w/ the -PDO. If this winter turns out being cold against seemingly growing odds, I do think it's good evidence that the game has changed. But certainly, it's looking like a warm winter is ahead.

That is certainly one way to look at it. Don, Wes, and many others certainly do a very good job with their analyses and outlooks. And Don's recent comments are not particularly encouraging. A lot of his conclusions are statistical-based. I'll bet that if you looked at the number of SE Winter storms over a period of years, correlated against the total number of SE storms, the statistical probability of a given storm being a Winter storm is pretty low, which is somewhat discouraging.

Last Winter, the sustained cold was front-loaded. We flipped in Jan. and Winter was pretty much over for the most part. It seems that there is growing consensus that Dec. of this year will be wasted, in terms of a sustained cold pattern. But, by no means would I write off the whole winter yet. There is so much we don't know about how the atmosphere behaves (see last Winter and the expectations for it). It might end up being warm the whole Winter. But I believe that we'll see some periods of cold and we'll have some storms to track. We just might have to wait a while.

[RevDodd]

When people say "pattern change" around here, they don't mean a useless reconfiguration of a vortex in Alaska that has almost no effect on the sensible weather here. They certainly would care if a trough developed over Japan unless that teleconnected to a trough here.

Hmmm: Now that you mention it, this anomaly over Central Japan looks like it could have implications for the Carolinas in about 3 weeks....

[WeatherNC]

Scroll through the phase plots, the UKME (Ukie ensemble) has verified well as of late, also the Euro ens (ECMF). Best case scenario, a 180 in the circle of death followed by a strong push into the 7 octant in 2 weeks. Worse case, the dive followed by a re-mergence in phase 3 or 4 in about 2 weeks. The second half of Dec is pretty much toast imo, sure we will have another isolated winter-wx threat or two, but it will be for the climo favored areas, i.e. elevation dependent, and without any mechanism to lock in cold, the SE as a whole is out of luck. Period between the 16-20th does have potential, but all indications are that it will be too warm for anything but RN. After that, week prior to Christmas is looking warm, period thereafter, who knows, but the signs continue to point towards transient shots of modified cold with no cooperation from the pna, nao, or ao. If this keeps up, first part of January is in trouble, with a likely shift to a cold regime getting pushed back to the second half of next month.

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/CLIVAR/clivar_wh.shtml

[kanc2001]

Looks like it's going to feel like Christmas in Miami this year.

remember those xmas'es in your childhood, wearing shorts and playing football in the front yard with your friends and cousins? well thats what I expect this year.

Hopefully I get those new golf clubs this year.

[SN_Lover]

EL NIÑO/SOUTHERN OSCILLATION (ENSO) DIAGNOSTIC DISCUSSION issued by CLIMATE PREDICTION CENTER/NCEP

8 December 2011

"During December 2011 - February 2012, there is an increased chance of above-average temperatures across the south-central and southeastern U.S. below-average temperatures over the western and north-central U.S. Also, above-average precipitation is favored across the northern tier of states, excluding New England, and drier-than-average conditions are more likely across the southern tier of the U.S."

[LithiaWx]

EL NIÑO/SOUTHERN OSCILLATION (ENSO) DIAGNOSTIC DISCUSSION issued by CLIMATE PREDICTION CENTER/NCEP

8 December 2011

"During December 2011 - February 2012, there is an increased chance of above-average temperatures across the south-central and southeastern U.S. below-average temperatures over the western and north-central U.S. Also, above-average precipitation is favored across the northern tier of states, excluding New England, and drier-than-average conditions are more likely across the southern tier of the U.S."

increased chance does not say a lot. Of course it's an increased chance it's a La Nina year.

Unless they mean increased from their previous forecast but that would be pretty bad considering they already went warm and drier than normal for the south central states. I hope they are not saying their confidence is increasing with this statement.

Also this thread needs a lock, a subtitle change or something done to it.

[EmersonGA]

increased chance does not say a lot. Of course it's an increased chance it's a La Nina year.

Unless they mean increased from their previous forecast but that would be pretty bad considering they already went warm and drier than normal for the south central states. I hope they are not saying their confidence is increasing with this statement.

Also this thread needs a lock, a subtitle change or something done to it.

I've been thinking for a while that this thread needs to be put out of its misery. It's been one of the ugliest threads I've seen in the SE forums.

[easternsnowman]

http://www.americanw...ost__p__1174358

Don pretty much drove a stake through the heart of the rest of this month.

He is not a professional met and he is primarily basing his assumptions on the ao.

[DixieBlizzard]

I've been thinking for a while that this thread needs to be put out of its misery. It's been one of the ugliest threads I've seen in the SE forums.

Good change to the avatar Emerson! Very appropriate! Hope you are doing well. At least we have cashed in on the rainfall lately.

[LithiaWx]

He is not a professional met and he is primarily basing his assumptions on the ao.

I've never met Don. From his posts you can tell he is extremely bright and his posts hold quite a bit of weight with many folks on this board, members and mets. Don while not a met is well respected and his posts are usually interesting and very pleasant to read with plenty of facts to backup what he is saying. He could be wrong like anyone else but I think he has this one pegged correctly. Not to mention there are plenty of mets who agree with his thoughts.

[donsutherland1]

http://www.americanw...ost__p__1174358

Don pretty much drove a stake through the heart of the rest of this month.

It could have been worse. At least it's the rest of the month, not the rest of the winter (I hope I'm wrong as I'd prefer a colder, snowier pattern). I still don't believe this winter will be as dismal as 2001-02 was.

[donsutherland1]

He is not a professional met and he is primarily basing his assumptions on the ao.

Only because the AO has been at extreme levels (2nd highest AO on record). When the AO is at extreme levels, it can dominate the pattern (2009-10 and 2010-11 during severely negative AO regimes offer two examples, one during an El Niño winter and the other during a La Niña one). Without the EPO-, things could have been even worse.

[SN_Lover]

increased chance does not say a lot(1). Of course it's an increased chance it's a La Nina year.

Unless they mean increased from their previous forecast but that would be pretty bad considering they already went warm and drier than normal for the south central states. I hope they are not saying their confidence is increasing with this statement.

Also this thread needs a lock, a subtitle change or something done to it.

"Synopsis: La Niña is expected to continue through the Northern Hemisphere winter 2011-12."

Basically, they are sticking with their 3 month forecast on Nov 17th.

Past 30 days departure from normal precipitation

(1)They are saying that their confidence was increasing on their original predictions.

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_advisory/ensodisc.html

[easternsnowman]

I've never met Don. From his posts you can tell he is extremely bright and his posts hold quite a bit of weight with many folks on this board, members and mets. Don while not a met is well respected and his posts are usually interesting and very pleasant to read with plenty of facts to backup what he is saying. He could be wrong like anyone else but I think he has this one pegged correctly. Not to mention there are plenty of mets who agree with his thoughts.

The ao alone is not enough if we have a good -epo +pna. Also many mets who have forecasted a cold snowy winter have not changed their thinking as of now. The mets who agree with him seem to already have a forecast of warmth to begin with and they agree perhaps because it backs up their forecasts? I do think the ao will go negative sometimes in january and it will be colder and snowier for a period, whether it is for the rest of the winter or only a few weeks well right now nobody knows. My problem with him that he relies on statistics.

[Southern Track]

Was it the December of 2000 that was so cold in the Southeast? I remember vividly in the Upstate of South Carolina the ponds in the area were frozen over from the consecutive days of highs in the 30's. We had several instances of wintry precip that month, including my B-day(Dec. 2nd). It was a winter lovers dream. Then, like a light switch, at the New Year the winter went POOF! We had no winter in the heart of January. Hopefully we can get a flip and hit the ground running for the New Year!

[LithiaWx]

The ao alone is not enough if we have a good -epo +pna. Also many mets who have forecasted a cold snowy winter have not changed their thinking as of now. The mets who agree with him seem to already have a forecast of warmth to begin with and they agree perhaps because it backs up their forecasts? I do think the ao will go negative sometimes in january and it will be colder and snowier for a period, whether it is for the rest of the winter or only a few weeks well right now nobody knows. My problem with him that he relies on statistics.

There are mets backing off a cold December who previously thought it would be cold and cutting yearly snowfall totals based on it. Unfortunately we don't have a +PNA it's been predominately negative and shows no signs of flipping and the NAO is still positive. We agree to disagree I'm not going to argue with you about it anymore than I have but you won't find many on the cold and snowy December bandwagon.

[beanskip]

Agree with this completely. I'm afraid one arguing that there will be a significant non-elevation snow this month is facing very, very long odds indeed.

Scroll through the phase plots, the UKME (Ukie ensemble) has verified well as of late, also the Euro ens (ECMF). Best case scenario, a 180 in the circle of death followed by a strong push into the 7 octant in 2 weeks. Worse case, the dive followed by a re-mergence in phase 3 or 4 in about 2 weeks. The second half of Dec is pretty much toast imo, sure we will have another isolated winter-wx threat or two, but it will be for the climo favored areas, i.e. elevation dependent, and without any mechanism to lock in cold, the SE as a whole is out of luck. Period between the 16-20th does have potential, but all indications are that it will be too warm for anything but RN. After that, week prior to Christmas is looking warm, period thereafter, who knows, but the signs continue to point towards transient shots of modified cold with no cooperation from the pna, nao, or ao. If this keeps up, first part of January is in trouble, with a likely shift to a cold regime getting pushed back to the second half of next month.

http://www.cpc.ncep....clivar_wh.shtml

[WeatherNC]

For the record, when DS and HM post, folks don't just listen, but the masses take notice. (Quartet)

Yeah, and I grab my

[NCSNOW]

Are we seeing the begining of a trend? Just the op GFS and didn't check the ensemble or Euro. I'll wait to see tomorrows runs beofre I start to sit up and take notice. Nao going Neg right before Christmas and pna shading pos.

http://raleighwx.americanwx.com/models/18zgfsindices.html

[calculus1]

The ao alone is not enough if we have a good -epo +pna. Also many mets who have forecasted a cold snowy winter have not changed their thinking as of now. The mets who agree with him seem to already have a forecast of warmth to begin with and they agree perhaps because it backs up their forecasts? I do think the ao will go negative sometimes in january and it will be colder and snowier for a period, whether it is for the rest of the winter or only a few weeks well right now nobody knows. My problem with him that he relies on statistics.

Huh?? All the more reason to respect what he says. I have problems with believing people's forecasts when they don't have statistics to back them up. I don't know whether he will be right or not (no one does until winter's come and gone and we can look back on it!), but your problem with him is that he uses statistics!! Really??!! So, for the record, in future cases, we should look for people who back up their forecasts with gut feelings, moon phases, and astrological signs? I don't understand this at all...

Statistics are not the only thing used in weather-forecasting, I'm sure, but you can't fault someone for having done research on past events and trying to create corollaries. I don't like his conclusions anymore than any other snow-lover, but I have to respect the argument.

Okay, I'm done...

[BullCityWx]

For the record, when DS and HM post, folks don't just listen, but the masses take notice. (Quartet)

Yeah, and I grab my

Yeah, I know we have a lot of new people around here but there's certain people you just don't question.

[calculus1]

For the record, when DS and HM post, folks don't just listen, but the masses take notice. (Quartet)

Yeah, and I grab my

I gather DS is donsutherland1, but, for the record, can you clarify who you are referring to by HM?

[WeatherNC]

I gather DS is donsutherland1, but, for the record, can you clarify who you are referring to by HM?

Search it, only HM I know of and not the inaccuwx type, other I woke up with EL several years back on a botched Eastern radio show.... QC nailed it, two folks I, or any other will not question, and these are them. Stay warm my friends, second half of Dec is looking like, early Jan too...

[donsutherland1]

Just so that others better understand my thoughts when it comes to the medium-range and beyond:

1. I place my greatest weight on the ensembles

2. Given the ensembles and actual data, I place emphasis on teleconnections, particularly in similar ENSO situations

3. When a teleconnection is at an extreme level, I place greater weight on it

4. Given that forecasting the durability of various regimes NAO-, AO+, etc., beyond the short range is subject to a high degree of error, I use statistics to add insight.

The ongoing AO+ regime reached extreme levels for December. In late November, some of the guidance was still hinting at a fairly imminent pattern change. The question was whether a change to cold weather was reasonable given an extreme AO+ regime (it would peak at the 2nd highest value on record).

Here's the 500 mb pattern forecast from all days in the 12/1-10 period when the AO reached +3.5 or above (1950-2010):

Such a pattern would suggest that readings would generally be warmer than normal during that 10-day period.

Here's how the pattern has verified so far (12/1-6):

IMO, a closer look at the AO cases from which the composite was drawn provided good insight into the pattern that has prevailed. Moreover, the warm anomalies have been so large during the first week of December that it is now highly likely that much of the East will have proved warmer than normal for the period even with the modest shots of cold air today and then again Saturday into Monday.

[Carvers Gap]

For the record, I like the 18z GFS - a lot. Doubt it will verify, but I still like it. Man, the AO on the CPC ensembles is a crazy lookin' hockey stick. I'm thinking something still isn't quite right there. Don, thanks for posting. As always, very good stuff.

[Mr Bob]

The ao alone is not enough if we have a good -epo +pna. Also many mets who have forecasted a cold snowy winter have not changed their thinking as of now. The mets who agree with him seem to already have a forecast of warmth to begin with and they agree perhaps because it backs up their forecasts? I do think the ao will go negative sometimes in january and it will be colder and snowier for a period, whether it is for the rest of the winter or only a few weeks well right now nobody knows. My problem with him that he relies on statistics.

Don relies on statistics....what do you rely on? I think I know where my money is going....

[donsutherland1]

For the record, I like the 18z GFS - a lot. Doubt it will verify, but I still like it. Man, the AO on the CPC ensembles is a crazy lookin' hockey stick. I'm thinking something still isn't quite right there. Don, thanks for posting. As always, very good stuff.

Thanks Carver's Gap.

I would like to see the 18z GFS verify. Unfortunately, I suspect that the 18z GFS ensembles probably have a better idea for the 11-15-day (12/19-23) timeframe.