SE Mid-Long Range Discussion

[oconeexman]

Robert right on cue with exccellent posts daily and thanks a ton phil for your input today. You 2 together along with matthew make a heck of a team for forecasting and analysis for our area which is a really tough one to forecast more than 48hrs out. We SE folks are truely blessed!!! Thank ya'll

[valkhorn]

In 2002 was our 6th biggest snowfall, in the SE we can still have a good winter with a bad pattern. Last year we were skunked in January and it was supposedly a great pattern.

The talk of patterns doesn't mean much when you realize that there have been decent snows in overall 'warm' patterns, and record breaking cold outbreaks in 'warmer than average' winters. Sometimes you can get snow in air that isn't all that cold but just cold enough for snow, and sometimes precip can lower the temperature enough for heavy snow. Patterns only mean that the probability for something to happen might be greater or lower - but not that it won't happen at all. When you realize that snow events in the deep south are already rare enough as it is (and some have been spoiled of late), then the talk of patterns, at least to me, becomes moot. Patterns only really mean wet/dry or cold/warm for a while, and you can still have a very cold pattern with little snow if it's dry, or if all the moisture falls before the cold air arrives.

The talk of patterns, to me, doesn't mean a whole lot in terms of predicting some random snow storm or lack thereof.

[Lee]

In 2002 was our 6th biggest snowfall, in the SE we can still have a good winter with a bad pattern. Last year we were skunked in January and it was supposedly a great pattern.

Maybe in your backyard of the SE. Parts of it did well.

[WeatherNC]

Maybe the bright spot in the 12z guidance (Euro still unknown), Canadian is bringing a good bit of energy east. I think the HPC discounted it in the morning final, and imagine they will throw it out again if it does not have support. Deep trough but very pos, and no mechanism to really turn it.

12z GFS @ 144 for comparison (UKMET would lean GFS/0z Euro, progressive flow, no real amplification, and some energy left back in the SW)

[Snowless in Carrollton]

Winter 2011-12 won't be as bad as 2001-02 ??? From what I recall, 2001-02 was a tremendous winter. We had a very nice snowstorm in Early January 2002. So since this winter won't be as bad as that winter, I guess we should expect even more snow than that winter ?

[LithiaWx]

The talk of patterns doesn't mean much when you realize that there have been decent snows in overall 'warm' patterns, and record breaking cold outbreaks in 'warmer than average' winters. Sometimes you can get snow in air that isn't all that cold but just cold enough for snow, and sometimes precip can lower the temperature enough for heavy snow. Patterns only mean that the probability for something to happen might be greater or lower - but not that it won't happen at all. When you realize that snow events in the deep south are already rare enough as it is (and some have been spoiled of late), then the talk of patterns, at least to me, becomes moot. Patterns only really mean wet/dry or cold/warm for a while, and you can still have a very cold pattern with little snow if it's dry, or if all the moisture falls before the cold air arrives.

The talk of patterns, to me, doesn't mean a whole lot in terms of predicting some random snow storm or lack thereof.

100 times out of 100 I would prefer a pattern like the past two years(with teleconnections that support a colder and snowier winter) to this steaming pile of bleep that we have this year. Who knows exactly what the rest of winter holds in store for the southeast but it's doesn't appear epic and I don't think it holds a candle to the past two seasons.

[Cheeznado]

12Z Euro shows a pretty strong short wave into the SE just after XMAS, enough for some pretty decent mountain snows but just a brief pretty minor cold shot elsewhere. Before that warm and quite a bit of rain- 3-4" for north GA.

[WeatherNC]

Euro takes a 996 low over Cape Cod @ 138hrs, 6z 12/26... weak slp starts to organize over SE AL @ 114 with a track towards coastal NE, wet Christmas for the SE, N GA, W NC and the eastern half of TN look to do well per the precip maps, all RN. Deep trough on the backside, 528dm 1000-500mb thickness into N GA and the western third of NC @ 144.

Should be a rapid rebound in temps after the 26th

[POWERSTROKE]

The problem with this statement in the south is that it obviously only takes one event to meet or exceed the areas in the south yearly snowfall average.

you are right. One snow of 8 inches and we have our average in my area

[WidreMann]

Don is one of the most respected posters when it comes to the medium and long range. So, I have little reason to doubt him right now. However, keep in mind that he is in the NE US and the term "East" is often referring to the mid-Atlantic and New England areas for the most part. Since the SE

can easily have a sig. different outcome from the NE in terms of temperature anomalies and especially in terms if snowfall since just one major storm could easily be enough to make it "snowy", I wouldn't give up in the SE even if Don ends up correct for the NE. Also, even if it ends up warmer than avg. in the SE, maybe it won't be top 20%.

I'd imagine that it's unlikely for the SE to be cold and snowy if the MA and NE are warm and rainy. There may be one or two counter-examples in the history books, but I wouldn't hang my hat on those.

[burgertime]

I'd imagine that it's unlikely for the SE to be cold and snowy if the MA and NE are warm and rainy. There may be one or two counter-examples in the history books, but I wouldn't hang my hat on those.

Ok ok, I'll bite. I'm not expecting us to be cold and snowy for a duration period. But there have been plenty of times points to the south and east have done better in terms of storms as opposed to the SE. Think people are more hanging their hat on the fact that we may get one or two storms that really overperform for us in this pattern.

[Bevo]

I wouldn't be surprised to see a major cutoff somewhere in the south-central to southeast US in the next 2 weeks. Back in the November 26-29 timeframe, a major vortex with well below normal heights invaded western Alaska and there was another pool of low heights between Greenland and Scandinavia, which teleconnects to possible cutoff in the southern US. That's exactly what happened, with the historic 5 contour cutoff over the Delta, and then snow Tenn. Valley.

Was that November 26-29 system the one that was pulling in cold air from a southwest wind? Give me a few more of those please.

[Cheeznado]

I think our best shot at snow will be from a strong closed low coming right overhead resulting in dynamic cooling of the column- as opposed to a -NAO driven WAA type snow where Gulf moisture comes in over an existing cold air mass. This means the chance of a major ice event could be a lot lower this season- fine by me, I do not like ice storms all that much.

[franklin NCwx]

What do the euro ensembles have for the 26th, is there still a third wave? Thanks.

I think our best shot at snow will be from a strong closed low coming right overhead resulting in dynamic cooling of the column- as opposed to a -NAO driven WAA type snow where Gulf moisture comes in over an existing cold air mass. This means the chance of a major ice event could be a lot lower this season- fine by me, I do not like ice storms all that much.

[WeatherNC]

This run of the Euro is close to a major storm imo... H5 @ 120hrs, if more energy ejects out of the SW/Baja (sometimes an ec bias), timing is off by 12hrs or a couple hundred miles difference in the placement of these vorts, we could be looking at a pretty big phase. I have all but thrown in the towel on winter type for the SE, cold air is just not there. NC snows I like to see cross polar flow, and this setup does not have it. Would not be surprised though to see this trend towards a bigger event for our friends to the north.

Global ensemble train-wreck continues... Maybe 1 or 2 have a similar look to the Euro, even 1 or 2 with a weak SE coastal ots. Early indications are yet another system around 192hrs

GFS mems @ 144

[GaWx]

I'd imagine that it's unlikely for the SE to be cold and snowy if the MA and NE are warm and rainy. There may be one or two counter-examples in the history books, but I wouldn't

hang my hat on those.

I'm defintely not hanging my hat on those or even predicting snowy and/or cold. I'm mainly just reiterating the obvious that it often only takes one or two major storms to bring much of the nonmountainous SE above avg. wintry precip.

[Cheeznado]

Euro ensembles not great- the Op is the cold outlier with the short wave after Xmas. Then it goes zonal. Except for the needed rain here the next 4 days, pretty boring.

[griteater]

PDO value for November came in strongly negative (-2.33) - http://jisao.washington.edu/pdo/PDO.latest. Negative PDO favors strong Pacific jet and -PNA

[griteater]

Current ENSO

[griteater]

Forecasted ENSO

[snowman22]

As far as the winter goes, I can remember the 08-09 winter which included the very warm Christmas, i was ready to give then March 1st came. ULLs can be the sneakiest.

[WeatherNC]

HPC extended

EXTENDED FORECAST DISCUSSION

NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD

229 PM EST TUE DEC 20 2011

VALID 12Z FRI DEC 23 2011 - 12Z TUE DEC 27 2011

...STILL CONSIDERABLE UNCERTAINTY WITH DETAILS OF POTENTIAL ERN

U.S. CHRISTMAS WEEKEND SYSTEM...

...PATTERN CHANGE TOWARD FLATTER MEAN FLOW OVER THE LOWER 48

EXPECTED NEXT WEEK...

MEDIUM RANGE GUIDANCE AGREES THAT THE MEAN PATTERN SHOULD TREND

TOWARD A MORE ZONAL CONFIGURATION BY NEXT MON-TUE AS FAST PACIFIC

FLOW STREAMS INTO THE CONUS. THIS REGIME IS FCST TO REPLACE A

MORE AMPLIFIED PATTERN EARLY-MID PERIOD... CONSISTING OF A RIDGE

BUILDING FROM THE ERN PAC INTO WRN NOAM AND A POSITIVELY TILTED

MEAN TROF FROM ERN CANADA INTO THE SRN ROCKIES/NRN MEXICO. MOST

IF NOT ALL MULTI-DAY MEANS BY D+8 SHOW A PREVAILING CORE OF

NEGATIVE HGT ANOMALIES ASSOC WITH A CLOSED LOW OVER ALASKA... WITH

TELECONNECTIONS RELATIVE TO THIS FEATURE SUPPORTING LOW AMPLITUDE

AND VERY BROADLY CYCLONIC FLOW. THE 06Z GFS AND TO A LESSER

EXTENT 00Z GFS ARE ON THE FAST SIDE OF THE SPREAD INCLUDING THE

00Z GEFS/ECMWF ENSEMBLE MEANS WITH THE ARRIVAL OF SHRTWV ENERGY...

WITH THE 06Z GFS SCENARIO LEADING TO FASTER THAN CONSENSUS

DOWNSTREAM PROGRESSION AS WELL. THE AMPLIFIED PATTERN IN PLACE

THRU MID-PERIOD SHOULD SUPPORT SLOWER PROGRESSION THAN INDICATED

BY THE 00Z/06Z GFS. MEANWHILE AROUND SUN-MON THE 00Z GFS MAY BE

OVERDONE WITH ITS SEWD EXTENT OF ITS TROF OVER THE EAST GIVEN THE

PERSISTENCE OF THE MEAN RIDGE OVER/NEAR THE BAHAMAS. THE 00Z

ECMWF CONFORMS BETTER TO ENSEMBLE GUIDANCE INTO DAY 6 MON. 00Z

ECMWF AMPLITUDE WITH FEATURES BY DAY 7 IS STILL POSSIBLE FROM THE

MULTI-DAY MEAN PERSPECTIVE BUT THE TREND TOWARD FLATTER FLOW IN

GENERAL AND SIGNIFICANT ENSEMBLE SPREAD WOULD FAVOR LEANING AWAY

FROM ITS SPECIFICS UNTIL BETTER CLUSTERING DEVELOPS.

BEFORE THE AFOREMENTIONED PATTERN CHANGE OCCURS... EXPECT ENERGY

REACHING THE PAC NW/BC AS OF EARLY DAY 3 FRI TO RELOAD THE E-CNTRL

CANADA TO SRN ROCKIES/NRN MEXICO MEAN TROF BY THE CHRISTMAS

WEEKEND. UNCERTAINTIES IN DETAILS OF THE INITIALLY SPLIT FLOW

OVER THE CONUS AND RELOADING OF THE MEAN TROF CONTINUE TO IMPACT

THE FCST OF LOW PRESSURE THAT MAY AFFECT SOME ERN AREAS DURING A

PORTION OF THE SAT-MON PERIOD. 00Z GEFS/ECMWF/CMC ENSEMBLE

MEMBERS ARE STILL NOT PARTICULARLY WELL CLUSTERED BUT THEIR

CORRESPONDING MEANS ARE SIMILAR IN DEPICTING A WAVE REACHING NEAR

NOVA SCOTIA BY EARLY DAY 6 MON... WHICH IS CLOSEST TO THE

TRACK/TIMING OF THE 00Z ECMWF. THIS REPRESENTS A SLOWER TREND

OVER THE PAST 12-24 HRS. OTHER OPERATIONAL SOLNS VARY FROM THIS

GROUP WITH THE 00Z GFS/UKMET MUCH FASTER... THE 06Z GFS QUITE FAR

OFFSHORE... AND THE 00Z CANADIAN SLOW AND MODERATELY OFFSHORE.

SHARP/SLOW DEPICTION OF 06Z GFS ENERGY ENTERING THE WRN CONUS AT

THE START OF THE FCST AND ITS FAST TIMING OF UPSTREAM FLOW LEAD TO

DISCOUNTING THE 06Z GFS OVERALL. SLOWER/MORE AMPLIFIED THAN

CONSENSUS NRN STREAM SHRTWV CROSSING THE NORTHEAST IN THE 00Z

ECMWF AND FAST EJECTION OF THE SRN SHRTWV IN THE 00Z GFS ON SAT

LOWER CONFIDENCE IN THEIR SOLNS... BUT AT LEAST THE AGREEABLE

ENSEMBLE MEANS YIELD MORE CONFIDENCE IN SOME VARIATION OF THE 00Z

ECMWF THAN ANOTHER OPERATIONAL FCST AT THIS TIME.

12Z UPDATE... EARLY IN THE PERIOD THE 12Z GFS IS LIKELY OVERDONE

WITH WWD EXTENT OF ENERGY REACHING THE WRN US-MEXICO BORDER.

HOWEVER BY THE WEEKEND THE 06Z/12Z GEFS MEANS AND TO SOME DEGREE

12Z UKMET INDICATE THAT A CLOSED LOW MAY FORM FARTHER NWWD THAN

PRIOR CONSENSUS. THIS EVOLUTION COULD BE PLAUSIBLE GIVEN THE

ESTABLISHED MEAN PATTERN BUT THE 12Z ECMWF SHOWS LITTLE TREND IN

THAT DIRECTION. DIFFS IN HANDLING THIS ENERGY AND OTHER ASPECTS

OF THE CONUS MEAN TROF MAINTAIN THE SPREAD IN SFC EVOLUTION OVER

THE EAST DURING THE PERIOD. CONSENSUS SUGGESTS THE 12Z GFS LOWERS

PRESSURES TOO MUCH OVER/NEAR NEW ENG SAT. THEN WITH THE POTENTIAL

EAST COAST SYSTEM SUN-MON THE UKMET HAS SLOWED FROM ITS 00Z RUN TO

A TRACK OFFSHORE FROM THE 00Z ECMWF. THE 06Z/12Z GEFS MEANS ARE

SLOWER THAN THE 00Z ENSMEAN/ECMWF CLUSTER WHILE THE CANADIAN IS A

SLOW AND WRN EXTREME. THE 12Z ECMWF MAINTAINS GOOD CONTINUITY IN

PRINCIPLE THOUGH WITH SLIGHTLY SLOWER TIMING. MEANWHILE THE GFS

REMAINS ONE OF THE FASTER SOLNS WITH PAC FLOW PROGRESSING INTO

NOAM MID-LATE PERIOD WITH THE 12Z GEFS MEAN/ECMWF FAVORING SLOWER

EROSION OF THE WRN NOAM RIDGE.

BASED ON DATA AVBL FOR THE UPDATED PRELIM ISSUANCE... THE DAYS 3-6

FRI-MON FCST STARTED WITH THE MOST AGREEABLE SOLN CLUSTER

CONSISTING OF A NEARLY EVEN WEIGHTING OF THE 00Z ECMWF/00Z GEFS

MEAN/00Z ECMWF ENSEMBLE MEAN. THE 00Z ECMWF WAS REMOVED AND

ENSEMBLE MEANS WEIGHTED EQUALLY FOR DAY 7 TUE DUE TO LACK OF

CONFIDENCE IN ECMWF SPECIFICS LATE IN THE FCST. 12Z GEFS

MEAN/ECMWF SOLNS APPEAR TO RECOMMEND MINIMAL CHANGE FOR THE FINAL

ISSUANCE ASIDE FROM TYPICAL DETAIL ADJUSTMENTS FOR COMMON IDEAS IN

12Z GUIDANCE EARLY IN THE PERIOD. SLOWER TENDENCY OVER THE PAST

DAY WITH THE POTENTIAL SAT-MON EAST COAST SYSTEM IN NON-GFS

GUIDANCE COULD SUPPORT A COMPROMISE WITH THE 12Z GEFS MEAN/ECMWF

TIMING BUT ENOUGH UNCERTAINTY EXISTS TO AWAIT ANOTHER MODEL CYCLE

BEFORE MAKING ANY REFINEMENTS.

BY EARLY NEXT WEEK THE MEAN PATTERN THAT SHOULD BECOME

INCREASINGLY DOMINATED BY PACIFIC FLOW SHOULD LEAD TO ABOVE NORMAL

DAYTIME TEMPS OVER MOST OF THE LOWER 48 AND INCREASED MOISTURE

REACHING THE PAC NW. AREAS FROM THE NRN HIGH PLAINS INTO THE UPR

MS VLY WILL LIKELY SEE THE MOST PERSISTENT WARMTH THRU THE PERIOD

WITH DAILY HIGHS OF 5-15 F ABOVE NORMAL THOUGH IT WILL STILL FEEL

CHILLY WITH BREEZY CONDS MOST DAYS. A RIDGE ALOFT BUILDING INTO

THE WEST DURING THE FIRST HALF OF THE PERIOD WILL SUPPORT A

WARMING TREND OVER THE WRN HALF OF THE NATION... IN PARTICULAR THE

SRN ROCKIES/CNTRL-SRN PLAINS WHERE HIGHS MAY BE 10-20 F BELOW

NORMAL AT THE START OF THE PERIOD FRI.

IN CONTRAST TO WRN/NRN AREAS... THE EAST WILL SEE A COOLING TREND

AFTER STARTING WITH ABOVE/WELL ABOVE NORMAL HIGHS LATE THIS WEEK.

A SLOW MOVING WAVY FRONT WILL FOCUS RNFL OVER THE SOUTHEAST

FRI-SAT. DETAILS OF SFC DEVELOPMENT NEAR THE EAST COAST IN THE

SAT-MON TIME FRAME REMAIN VERY UNCERTAIN WITH SOME POTENTIAL FOR

WINTRY PCPN OVER PORTIONS OF THE INTERIOR NORTHEAST AND RAIN

FARTHER S. IF THIS SYSTEM IS SUFFICIENTLY STRONG THE APLCHNS MAY

SEE SOME SNOW AS THE SYSTEM DEPARTS. MEANWHILE A PERIOD OF LAKE

EFFECT SNOW IS ALSO POSSIBLE BY THE LATTER HALF OF THE PERIOD.

RAUSCH

[wxgeek]

http://www.cpc.ncep.noaa.gov/products/predictions/814day/814temp.new.gif

With that said, the map still showing the SE to a good part in the below normal range for temps.

[WeatherNC]

http://www.cpc.ncep.noaa.gov/products/predictions/814day/814temp.new.gif

With that said, the map still showing the SE to a good part in the below normal range for temps.

FL looks to cool down finanlly. Family around MLB says it has been warm, 80's...

18z GFS cuts off not one but two ull's out west, nice

http://raleighwx.americanwx.com/models/gfs/18zgfs500mbvort090.gif

Southern slider, crawls along the SE coast from GA-NC then OTS on Christmas, no storm after, at least through 172, just a mid-major RN event on Christmas. Some evidence of cold coming down on the backside as it exits, WV, central Apps. Hybrid type cad sig showing up at 108 with a 1031 high in central PA for favored areas, would likely be a quick event before transition to RN.

[wxgeek]

well so far the 18z GFS is showing no surpises.

[WeatherNC]

well so far the 18z GFS is showing no surpises.

Don't know if I have ever seen a 1019 low put down this much qpf, has the Christmas storm, southern track, not much after.

Lots of rn (0-72 & 72-144) precip panels

Does get much farther than N VA

[LithiaWx]

18Z looks pretty tame for the southeast, active but all rain for most of us. The interesting thing from this run is a nor'easter with lots of snow verbatim for the NE on New Years Eve, there might be some snow verbatim for parts of the southeast but it's too far out for details and doesn't look all that exciting for us right now but it's way out there in the med-long range, regardless it looks like potent system.. Wouldn't that be cool watching the new years festivities in New York City on live TV with a major snowstorm raging in the background. It's the GFS out to 10 days but it's a fun look regardless and is more fun to talk about than warm, warm, warm....

[franklin NCwx]

Gfs is folding to the euro again. How many times have we saw this. Would not be surprised to see the 0Z crank the Christmas storm.

WeatherNC, is the jma still ahead of the gfs at day 5?

[wxgeek]

I'd be happy if my NOAA source would get past the 228 hr for the 18z

[LithiaWx]

I'd be happy if my NOAA source would get past the 228 hr for the 18z

Give this site a shot, you will probably like it.

http://www.instantweathermaps.com/