SE Mid-Long Range Discussion

[burgertime]

Lots of energy coming down into a long wave that is a little deeper than 18z through 144, looks like a phase, maybe a little later. Getting inside day 6, ens are a train wreck, but if the 3rd system holds, I would expect the other 0z globals to trend toward.

We're going to have big battles from run to run with that 3rd system with the models. My prediction is the Euro comes in totally different. Either way I'll find out in the morning. Time for me to sleep!

[lilj4425]

My second post was referring to the storm system with the wintry possibility on the 27th. Sorry if that was misleading.

Ohhh...gotcha. Thought you were talking about the same day at first.

[burgertime]

Hour 216 on the GFS looks horrible. GFS broke out the flame thrower on 75% of the US.

[Gastonwxman]

What a buzzkill but as should be expected, you're going to have wild swings from one run to another. Not worried about it just yet unless it starts becoming a new trend.

[jrips27]

Hour 216 on the GFS looks horrible. GFS broke out the flame thrower on 75% of the US.

GFS really isn't that bad though temp wise past 5 days. Its slightly mild but its not a full blown torch.

Day 6-10

[GaWx]

Fwiw, 0Z Doc gives Tony over 2" of qpf for Christmas from 3 different systems between now and then.Congrats, Mr. T! Also, good CAD for W NC may be giving them some ZR the night before Christmas.

[dsaur]

Fwiw, 0Z Doc gives Tony over 2" of qpf for Christmas from 3 different systems between now and then.Congrats, Mr. T! Also, good CAD for W NC may be giving them some ZR the night before Christmas.

Thanks for the great news Larry! Hope the Doc Sees. From last week when the models were blasting us finally, until the last few runs when things looked to put the bulk up north again...I've been maintaining hope. Need to get these systems down south of us! Split flow brings the sw's into the gulf, then on to the southeast. First piece of the puzzle Then some cold can phase.

A bunch of rain would sure be a great present!! T

[GaWx]

Thanks for the great news Larry! Hope the Doc Sees. From last week when the models were blasting us finally, until the last few runs when things looked to put the bulk up north again...I've been maintaining hope. Need to get these systems down south of us! Split flow brings the sw's into the gulf, then on to the southeast. First piece of the puzzle Then some cold can phase.

A bunch of rain would sure be a great present!! T

More 0Z Doc good news for Tony: a 4th system, a GOM miller A, gives Mr. T another solid 1.25"! So, well over 3" for this run. We can call the 0Z Doc the soil Doc for his area!

Due to the fact that this winter's snow prospects are rumored to be not as good as the prior winter, Tony has been awarded a special sponsor's exemption from the rule that wanting rain is evil during meteorological winter. This exemption has been awarded for the period up through 1/10. Any extension of the exemption would require our sponsor's ok.

[dsaur]

More 0Z Doc good news for Tony: a 4th system, a GOM miller A, gives Mr. T another solid 1.25"! So, well over 3" for this run. We can call the 0Z Doc the soil Doc for his area!

Due to the fact that this winter's snow prospects are rumored to be not as good as the prior winter, Tony has been awarded a special sponsor's exemption from the rule that wanting rain is evil during meteorological winter. This exemption has been awarded for the period up through 1/10. Any extension of the exemption would require our sponsor's ok.

Gosh, Larry, I don't know what to say! I'm just so happy. Gosh, well, I want to thank my mom...hi, mom, and, well, you Larry, for teaching me the power of climo! And Foothills for letting me glimpse the maps through his eyes. To look into the moving fluid, and see patterns in the swirls! And, well, American Wx for sponsoring this great prize!! And all my friends out there. You guys are great! And, oh yeah, Mr. Cheez for that necessary face slap when it just gets too giddy down in here, lol. T

[Isopycnic]

FXUS62 KRAH 200829

AFDRAH

AREA FORECAST DISCUSSION

NATIONAL WEATHER SERVICE RALEIGH NC

323 AM EST TUE DEC 20 2011

[CUT]

.LONG TERM /THURSDAY THROUGH MONDAY/...

AS OF 259 AM TUESDAY...

THE INITIAL FRONT IS EXPECTED TO STALL OVER CENTRAL NORTH CAROLINA

WED NIGHT AND EARLY THU AS THE STUBBORN SUBTROPICAL RIDGING

CONTINUES ALONG THE SOUTH ATLANTIC COAST. MODELS ARE IN GENERAL

AGREEMENT IN THAT THE FRONT WILL BEGIN TO RETURN AS A WARM FRONT

DURING THURSDAY AS ANOTHER WAVE APPROACHES THE TENNESSEE VALLEY AND

APPALACHIANS IN THE SW FLOW ALOFT. THE EUROPEAN OPERATIONAL RUNS AT

12Z/19 AND 00Z/20 WERE IN THE MIDDLE OF ALL GUIDANCE IN THE TRACK OF

THE WAVE THU NIGHT ACROSS WESTERN NC INTO SOUTHERN VA. THE NAM TRACK

WAS WELL WEST OF THE EC RUNS... WITH THE GFS OPS MODEL SHEARED AND

TO THE EAST. AS HAS BEEN MENTIONED MUCH THIS COOL SEASON THUS FAR...

WITH THE STRONG PHASE OF THE AO AND RESULTANT SUBTROPICAL RIDGE OVER

THE SOUTH ATLANTIC STATES OR JUST OFFSHORE IN PLACE... THE FAVORED

STORM TRACK WILL CONTINUE TO BE JUST TO OUR WEST AND NORTH WITH OUR

REGION CONTINUING TO BE OVERWHELMED BY WARM AIR. THE MOST

SIGNIFICANT RAIN WILL CONTINUE TO BE ALONG AND LEFT OF THE STORM

TRACKS... WITH MUCH MORE SHOWERY AND LIGHTER QP FORECAST FOR THE

EASTERN AND ESPECIALLY SE SECTIONS OF OUR REGION. SENSIBLE WEATHER

THURSDAY INTO FRIDAY WILL INCLUDE... MILD WEST TO WARM EAST WITH

SHOWERS... ESPECIALLY WEST AND NORTH... AND A CHANCE OF SHOWERS SE.

HIGHS 60S TO LOWER 70S SE. LOWS THU NIGHT 50S EXCEPT LOWER 60S SE.

HIGHS FRIDAY WILL BE COOLER 50S NW TO UPPER 60S SE.

THERE ARE SIGNS THAT THE SUBTROPICAL RIDGE MAY BREAK DOWN ENOUGH

LATE IN THE WEEK INTO THE WEEKEND TO ALLOW A COLD FRONT TO PUSH WELL

TO OUR SOUTH. THIS IS FORECAST TO OCCUR FRIDAY INTO SATURDAY DRIVEN

BY A MODERATELY STRONG 1030 MB HIGH THAT TRACKS FROM THE GREAT LAKES

TO PA FRI... THEN OFFSHORE SAT. THE STRONGLY CONFLUENT FLOW ALOFT

SUPPORTS THIS PROGRESSIVE COLD HIGH. THEREFORE... THE LOW LEVEL CAA

SHOULD OCCUR JUST BEFORE AND AT THE BEGINNING OF THE NEXT STORM.

HOWEVER... CURRENT 1000/850 MB AND 850/700 MB THICKNESS FORECASTS

CONTINUE TO INDICATE THE THREAT OF ANYTHING FREEZING/FROZEN WOULD

REMAIN WELL TO OUR NORTH POSSIBLY INTO PORTIONS OF NORTHERN VA.

THE EC IS AGAIN FAVORED WITH THE MAIN STORM TRACK SOLUTION. THIS

TIME AROUND IT APPEARS THAT CENTRAL NC WILL BE ON THE COLD SIDE OF

THE BOUNDARY (IF INDEED THIS VERIFIES)... WITH THE STALLED BOUNDARY

NEARER THE COAST THIS TIME. THEN... THE MAIN LOW IS FORECAST TO

DEVELOP ALONG THE COASTAL AREA AND MOVE NORTH UP THE COAST. AGAIN...

DUE TO THE PROGRESSIVE NATURE OF THE COLD HIGH TO OUR NORTH... AND

THE WARM MID LAYERS DUE TO OUR PROXIMITY TO THE SUBTROPICAL RIDGING

JUST OFF THE SE COAST... ONLY RAIN IS EXPECTED FOR A PORTION OF DEC

24-25... UNLIKE LAST YEAR WHEN WE WERE HIT WITH A MAJOR SNOW.

CONFIDENCE IN THE OVERALL PATTERN IS HIGH... RAIN AS PREDOMINATE

P-TYPE IS HIGH... BUT THE TIMING/STRENGTH OF THE SYSTEM STILL

AVERAGE FOR NOW. SIGNIFICANT QPF (1+ INCH) WILL BE POSSIBLE

DEPENDING ON THE STRENGTH OF SYSTEM.

SENSIBLE WEATHER WILL INCLUDE... MOSTLY CLOUDY FRIDAY AND FRIDAY

NIGHT. HIGHS 60 NW TO NEAR 70 SE. TURNING COOLER FROM THE NE DURING

THE DAY. LOWS IN THE UPPER 30S NW-N TO UPPER 40S SE. PERIODS OF RAIN

AS EARLY AS MID DAY SATURDAY INTO SUNDAY. HIGHS IN THE 40S TO LOWER

50S SE. LOWS IN THE MID 30S TO LOWER 40S. RAIN/DRIZZLE ENDING

SUNDAY. HIGHS IN THE MID 40S TO MID 50S. PARTLY CLOUDY MONDAY WITH

LOWS 30-35. HIGHS 45-50.

[NCSNOW]

At hour 129 Euro gives Mtns good snow, then really goes on to cover interior MA and NE. After this another Mtn snow comes in from the NW out towards hour 172 ish. Can't discern the surface temps in piedmont/foothills with the CAD.

[ams30721us]

Good morning all. Looks like model madness is still the rule as we go through this week for the upcoming weekend pattern and into next week. 00z GFS looks to have reverted back to its regular progressive frontal passage look from yesterdays 6z morning run.

Uploaded with ImageShack.us

Mean While the 00z Euro puts all the energy the system before Christmas and brings a weak wave to the north Christmas night that might spit out a few flurries and bring in much colder air. On the other hand it continues to be consistent on a strong cutoff low sometime next week deep in the south.

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Finally the CMC provides us with the eye candy of the overnight and the most interesting solution of them all in that Sunday Night-Monday timeframe or so.

URL=http://imageshack.us/photo/my-images/827/f168cmc.gif/][/url]

Uploaded with [url=http://imageshack.us/photo/my-images/254/f180cmc.gif/'>

Uploaded with ImageShack.us

Uploaded with ImageShack.us

[FoothillsNC]

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.

Now coming up, all models have another anomalously deep vortex coming into Alaska within 10 days. So far, none I see show a cutoff downstream, but keep an eye on future runs...one might "pop up" soon. I won't say if it will be cold enough or the details of it, but odds are, it'll happen.

Height comparison, and my location of approximate cutoff in red:

[Brick Tamland]

It's good to see all these systems coming through the next few days. Maybe with all this energy around we'll get something good after Christmas.

[phil882]

Major model disagreement between the GFS And the ECWMF continues. In fact, pretty much the only feature they agree on is the large ridge that is expected to amplify over the Western United States in the day 3-5 period. Check out this quick animation between the 120 hour GFS and ECWMF below.

I want to point out a couple of features. First, as I already mentioned, both show a pretty amplified ridge over the west coast. This will allow some sort of deep troughing to carve itself out around Christmas time in the east, despite the continuing +AO. So with this mean state in mind, the main different on whether or not there will be a storm will be dictated by how much vortmax consolidation we get. Note that both the GFS and the ECWMF so a very convoluted pattern, one that suggest there will be major run to run discontinuity over the next 5 days leading up to this synoptic pattern.

I'd argue that there is potential here for a much stronger system than the modeling is currently indicating given the strong ridging over the West, and its just a matter of how the pieces of energy interact with one another. The ECWMF seems to be playing to it typical bias of hanging out energy too far to the west (in fact it cuts off an upper level low over Mexico). The GFS meanwhile keeps this trough more progressive and further north with the mean flow, which allows for some degree of phasing with the polar jet (a bit too late for a significant system, however). The ECWMF does eventually develop a system by the 26th, but it fails to include the piece of energy that is kept behind in Mexico.

The bottom line is that there still quite a bit of uncertainty, but my hunch is there is a better than normal chance of a significant system during the Christmas Time frame.

[franklin NCwx]

Thanks for the update Phil. I guess by stronger system, you could get the cmc solution?

Major model disagreement between the GFS And the ECWMF continues. In fact, pretty much the only feature they agree on is the large ridge that is expected to amplify over the Western United States in the day 3-5 period. Check out this quick animation between the 120 hour GFS and ECWMF below.

I want to point out a couple of features. First, as I already mentioned, both show a pretty amplified ridge over the west coast. This will allow some sort of deep troughing to carve itself out around Christmas time in the east, despite the continuing +AO. So with this mean state in mind, the main different on whether or not there will be a storm will be dictated by how much vortmax consolidation we get. Note that both the GFS and the ECWMF so a very convoluted pattern, one that suggest there will be major run to run discontinuity over the next 5 days leading up to this synoptic pattern.

I'd argue that there is potential here for a much stronger system than the modeling is currently indicating given the strong ridging over the West, and its just a matter of how the pieces of energy interact with one another. The ECWMF seems to be playing to it typical bias of hanging out energy too far to the west (in fact it cuts off an upper level low over Mexico). The GFS meanwhile keeps this trough more progressive and further north with the mean flow, which allows for some degree of phasing with the polar jet (a bit too late for a significant system, however). The ECWMF does eventually develop a system by the 26th, but it fails to include the piece of energy that is kept behind in Mexico.

The bottom line is that there still quite a bit of uncertainty, but my hunch is there is a better than normal chance of a significant system during the Christmas Time frame.

[phil882]

Thanks for the update Phil. I guess by stronger system, you could get the cmc solution?

Potentially... I actually hadn't checked the CMC previous to posting my thoughts. It seems to depict a more intermediate solution where the northern stream remains further north, and the trough that digs down into Texas continues to remain progressive, instead of getting stuck in Mexico like the ECMWF suggest. Another complicating factor is that even though we do establish some ridging out west, it looks to quickly get beat down by the powerful Pacific Jet which is a mainstay during La Nina winters. As this ridge gets overwhelmed by the Pacific jet, it will tend to de-amplify the pattern in the long range, back to a zonal regime. So we have a relatively small window that will allow for a good trough to get into the east and allow a nice system to develop. That can still happen if we can get the shortwave features within the longwave trough to cooperate together rather than remain fragmented.

The problem with making a forecast one way or the other right now is that most of these northern stream shortwaves are still over the Pacific this far out, so we won't have good sampling of these features until within 72 hours of the potential system. Complicated Pattern + Poor Sampling = Very poor run to run continuity, so expect to see some pretty large changes in the modeling especially in the 3-5 day range.

[DixieBlizzard]

Thanks Robert and Phil!

You really nailed that last cutoff low Robert so good luck with your forecast!

[DaculaWeather]

Glad to see you still posting here Phil!

[msuwx]

As you and Robert have indicated, it's a crazy pattern. It is not every day you have this much chaos in the upcoming pattern. Just pieces of energy and disturbances everywhere. It will remain next to impossible to have any real confidence beyond about day 2 or so. It is amusing to see the models drastically change from one run to the next.

If you enjoy the weather, this is fun to watch and forecast. I am as big a snow fan as there is, but to me, the challenge of forecasting in this pattern is something I really enjoy. Sure beats a 594dm death ridge in July.

Potentially... I actually hadn't checked the CMC previous to posting my thoughts. It seems to depict a more intermediate solution where the northern stream remains further north, and the trough that digs down into Texas continues to remain progressive, instead of getting stuck in Mexico like the ECMWF suggest. Another complicating factor is that even though we do establish some ridging out west, it looks to quickly get beat down by the powerful Pacific Jet which is a mainstay during La Nina winters. As this ridge gets overwhelmed by the Pacific jet, it will tend to de-amplify the pattern in the long range, back to a zonal regime. So we have a relatively small window that will allow for a good trough to get into the east and allow a nice system to develop. That can still happen if we can get the shortwave features within the longwave trough to cooperate together rather than remain fragmented.

The problem with making a forecast one way or the other right now is that most of these northern stream shortwaves are still over the Pacific this far out, so we won't have good sampling of these feature until within 72 hour of the potential system. Complicated Pattern + Poor Sampling = Very poor run to run continuity, so expect to see some pretty large changes in the modeling especially in the 3-5 day range.

[metwannabe]

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.

Now coming up, all models have another anomalously deep vortex coming into Alaska within 10 days. So far, none I see show a cutoff downstream, but keep an eye on future runs...one might "pop up" soon. I won't say if it will be cold enough or the details of it, but odds are, it'll happen.

Height comparison, and my location of approximate cutoff in red:

I've been on here a long time but have rarely posted....love to read such great insight!! Doesn't the Euro show a cutoff in the location you outlined at hour 240 from the 0z (I know it's way out there but seems to have been pretty consistant) and this would line up with your comments....or am I seeing something different?

[LithiaWx]

Don S. just drove another stake right through the heart of winter this morning.

Thanks Keith LI.

Right now, I don't think Winter 2011-12 will be as bad as 2001-02. But it probably will fall among the bottom 20% of winters in terms of warmth and lack of snowfall in the East.

[ams30721us]

Don S. just drove another stake right through the heart of winter this morning.

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.

[GaWx]

Don S. just drove another stake right through the heart of winter this morning.

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%.

[LithiaWx]

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.

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 hear ya guys and I agree. With how respected Don is I thought it was worthy to drop in this thread. Sounds like he's not banking on much of a pattern shift this year. I guess we are just going to have to hope we can make some lemonade out of this pattern we have. Robert has me optimistic which is nice that he thinks we could get something out of this pattern eventually.

[burgertime]

Potentially... I actually hadn't checked the CMC previous to posting my thoughts. It seems to depict a more intermediate solution where the northern stream remains further north, and the trough that digs down into Texas continues to remain progressive, instead of getting stuck in Mexico like the ECMWF suggest. Another complicating factor is that even though we do establish some ridging out west, it looks to quickly get beat down by the powerful Pacific Jet which is a mainstay during La Nina winters. As this ridge gets overwhelmed by the Pacific jet, it will tend to de-amplify the pattern in the long range, back to a zonal regime. So we have a relatively small window that will allow for a good trough to get into the east and allow a nice system to develop. That can still happen if we can get the shortwave features within the longwave trough to cooperate together rather than remain fragmented.

The problem with making a forecast one way or the other right now is that most of these northern stream shortwaves are still over the Pacific this far out, so we won't have good sampling of these features until within 72 hours of the potential system. Complicated Pattern + Poor Sampling = Very poor run to run continuity, so expect to see some pretty large changes in the modeling especially in the 3-5 day range.

Thanks Phil, always love your posts and always learn something. IIRC one of the storms in Feb. had a slightly similar setup with the model madness and we had to wait till the vort energy was ejecting into the west coast (with some sampling) before we had any clue what might actually happen...but those are sometimes the funnest to track as Matt East also pointed out. Makes for some fun but long nights. Hope you keep checking in on us and give us your insight!

[FallsLake]

The 12z NAM does look a little colder and little different with the setup at 84 hours compared to the 6z GFS at 90 hours.

Below is 12z NAM at 84 hours. The GFS (6z) was not pushing cold air down like NAM.

[packbacker]

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%.

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.

[packbacker]

Well completely different run on the 12z GFS as compared to the 0z GFS, leaving the energy way back, even worse than the 0z Euro.

[GaWx]

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.

Yep, that's the beauty of living in the SE where big snows are a novelty for much of the region. Despite it being warm and quite snowless in the NE US, KATL had a great winter snowwise in 2001-2 with over 200% of its longterm avg. snowfall. Also, temp.'s were above avg. but the anomaly wasn't close to as big as it was in the NE US. (Of course, the swings are typically larger in the NE.)

1972-3 was another great winter (epic in some cases) for snow/ice for much of AL/GA/SC/ and at least E NC whereas the NE did quite poorly.

Neither winter had much before 1/1.