06Z Models 12/22/10

[A-L-E-X]

the EURO did not accelerate the system off to the east, what are you talking about? the EURO actually has the thing stalling and pulling back towards the coast before exiting stage right. it depicts a PROLONGED crippling east coast storm.

You wonder sometimes if some of these people actually know how to read maps lol.

[RUNNAWAYICEBERG]

I'm usually psyched about a huge storm approaching, but my gut feeling is telling me that the euro is going to shift south

thankfully mother nature doesnt rely on your gut, but physics and stuff like that.

EURO hasnt shifted in 3 straight runs. folks last nite were talking about they expect the 0z run to shift SE and it didnt. if it does, its still not trend unless tonites 0z follows it up.

[RUNNAWAYICEBERG]

You wonder sometimes if some of these people actually know how to read maps lol.

seriously....and i suck at this. but all you have to do is NOT look at your backyard and pay attention to the METs on here.

[A-L-E-X]

thankfully mother nature doesnt rely on your gut, but physics and stuff like that.

EURO hasnt shifted in 3 straight runs. folks last nite were talking about they expect the 0z run to shift SE and it didnt. if it does, its still not trend unless tonites 0z follows it up.

Admittedly, we'd much rather have this scenario than if the euro and gfs role reversed. We've seen how well that has played out over the years lol. Basically that's how the euro got its famous nick name.

[SP]

folks read HPC.... early am ideas?

Looks like HPC is going with the ECMWF for the most part.

...EUROPEAN CENTRE GUIDANCE STAYS THE COURSE ON POWERFUL EAST

COAST STORM DECEMBER 26-27...

WILL STICK WITH THE CONSISTENT ECMWF FOR THE PRELIMINARY FRONTS

AND PRESSURES FOR DAYS 3-7. FOR THREE CONSECUTIVE MODEL CYCLES...THE DETERMINISTIC ECMWF HAS INDICATED A MASSIVE...DEEP...

SLOW-MOVING CYCLONE HUGGING THE C AROLINA AND MID ATLANTIC COASTS THE TWO DAYS FOLLOWING CHRISTMAS. THE ECMWF AND

UKMET WERE THE FIRST OF THE GLOBAL NUMERICAL MODELS TO SWITCH FROM TRACKING THIS WAVE ALONG 40N THROUGH THE MIDWEST...TO A SUPPRESSED

PATH ACROSS THE DEEP SOUTH.

SINCE THIS BREAK-AWAY...THE UKMET SPLIT OFF EVEN FARTHER SOUTH...WITH THE ECMWF LOCKING ONTO AN EVOLUTION THAT TAKES THE DEVELOPING

LOW TO THE FLORIDA PANHANDLE AND THEN SHARPLY UP THE EASTERN SEABOARD. THE GEM GLOBAL FOLLOWED

THE EUROPEAN CENTRE TRACK ON ITS 00Z/21 RUN...BUT HAS SWUNG THE SYSTEM OUT WIDER OVER THE ATLANTIC THE LAST TWO RUNS. THE GFS HAS

SHIFTED TO THE SOUTHERN ROUTE ACROSS THE GULF STATES ON ITS CURRENT RUN...BUT LIKE THE GEM GLOBAL...DIRECTS THE CYCLONE WELL

SOUTH AND EAST OF CAPE HATTERAS.

THE ECENS MEMBERS HAVE AVERAGED CLOSE TO THE DETERMINISTIC ECMWF... WITH MANY MEMBERS FOLLOWING IT EXACTLY...AND OTHERS TRACKING A BIT FARTHER

OFFSHORE. THE EUROPEAN CENTRE GUIDANCE HAS THE ADVANTAGE IN DEVELOPMENTAL SYSTEMS WITH ITS HIGH RESOLUTION...AND IS FURTHER AIDED BY

ITS 4D-VAR ANALYSIS IN GENERAL. ITS ENSEMBLE MEMBERS ARE MORE HIGHLY RESOLVED THAN THE GEFS MEMBERS...AND WITH DYNAMIC...DEVELOPMENTAL

SYSTEMS...THE EUROPEAN GUIDANCE SHOULD HAVE THE EDGE.

INDEED...THE GEFS MEAN HAS BEEN CONSISTENTLY FLATTER WITH THE PATH OF THE BIG STORM...WHICH IS CERTAINLY IN LINE WITH THE LOWER

RESOLUTION. EVEN SO...FOUR 00Z/22 GEFS MEMBERS STILL TRACKED COMPARABLY TO THE ECMWF...SHOWING A DEEP NOREASTER AND A HIGH

IMPACT STORM FOR THE MAJOR METROPOLITAN AREAS ASTRIDE INTERSTATE 95 FROM WASHINGTON TO BOSTON. TO WIT...THESE GEFS MEMBERS ARE

GOING AGAINST THEIR LOWER RESOLUTION/LESS DEVELOPMENTAL NATURE. THE ECMWF HAS MUCH CLIMATOLOGY ON ITS SIDE AS WELL...WITH ITS

TRACK WEST OF THE GULF STREAM...AND THE BOMBING PHASE NEAR AND NORTH OF CAPE HATTERAS.

THE MOST UNUSUAL...AND THREATENING...ASPECT OF THE ECMWF FORECAST IS THE RELATIVELY LOW LATITUDE AT WHICH THE STORM MATURES AND

STALLS/LOOPS. MORE TYPICALLY...SYSTEMS WILL CLOSE OFF AND HOWVER OVER THE WATERS SOUTH OF NOVA SCOTIA...AS WITH THE MOST RECENT

CYCLONE STILL AFFECTING DOWNEAST MAINE. THE ECMWF SHOWS THE UPCOMING CIRCULATION COMING TO A HALT JUST EAST OF THE DELMARVA

PENINSULA...WHICH PUTS THE VERY POPULATED AREAS OF THE EASTERN MID ATLANTIC...LONG ISLAND...AND SOUTHERN NEW ENGLAND IN A PROLONGED

PERIOD OF HIGH WINDS AND HEAVY PRECIPITATION...MOSTLY SNOW. THE EXTRAORDINARY NEGATIVE NAO THIS MONTH COULD CERTAINLY SUPPORT SUCH

AN ANOMALY. EVEN BEFORE THE RAPID DEEPENING PHASE OF THE SYSTEM...AREAS OF THE DEEP SOUTH FROM THE INTERIOR GULF COAST

STATES TO GEORGIA AND THE MOUNTAINS AND PIEDMONT OF THE CAROLINAS MAY SEE A VERY RARE WHITE CHRISTMAS...AGAIN...CONSISTENT WITH THE

REMARKABLE DISRUPTION AT HIGH LATITUDES.

So that sounds like a raising the upper lip growl which comes before a bark/woof.

BTW DT nice to see you around again!

[ace0927]

To be fair with the last non-storm, the euro did shut the gfs snowstorm solutions down with an out to sea solution 6-7 runs in a row med-long range (prior to that 2 run blip at 72 out). I'm not sure what happened with those 2 runs, but remember the other guidance shifted west as well at 12z that day, scraping the coast and blasting New England. So did the euro take some bad data and run with it the most? Most definitely, but the other models were bringing it back west as well during that 12z suite.

Now, here we see the euro showing an epic blizzard 4-5 runs in a row now in the med-longer range...I'm not sure where it goes from here. I'm definitely concerned it ends up east like the other guidance, but as long as the euro is showing something big consistently, I have hope. It's the same principal, but inverse circumstances from when the euro is playing "Dr. No" against the other guidance showing a snowstorm.

great post- i was going to post this in response to Wes's comment abt it being the last model to show a big storm last week. It had one hiccup in 7 or 8 model runs...7/8 is still 87.5%

and here its not like the EC just came up with an extreme solution out of the blue- it has shown it consistently for a few days now.

[ace0927]

So let's pretend the GFS doesn't exist, what other guidance is supporting what the Euro is dishing out? A few of it's ens members? Maybe? I pose this question seriously.

the GGEm is very close to the EC...

[showmethesnow]

Not sure why people are hung up on the GFS. Yes it still shows out to sea at this point but if you compare from a couple of days ago its had a major and steady trend towards the Euro. If you also look at the assem members of the GFS for the last several runs they are having more and more pop up with the Euro solution only to the south a east a little. From what I understand and I could be wrong, the lower resolution models have more difficulty in phasing systems thus a south and east bias. If this is the case then it would look promising that the Euro has the right idea. Not saying it's going to be exactly what it is showing at this point but something very similar. I wouldn't be surprised if in the next 3 or 4 runs you see the GFS come on board with the Euro.

[easternsnowman]

9z SREF's look really bad for a storm imho

This model is not even worth mentioning.

[IsentropicLift]

You wonder sometimes if some of these people actually know how to read maps lol.

Euro hr 144

Euro hr 168...

looks like a pretty fast jump in the last frame to me

[CTWeatherFreak]

Looks like an HPC update since Dave's post a few minutes ago:

PRELIMINARY EXTENDED FORECAST DISCUSSIONNWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD859 AM EST WED DEC 22 2010 VALID 12Z SUN DEC 26 2010 - 12Z WED DEC 29 2010 ...HIGH UNCERTAINTY WITH TRACK/IMPACT OF POWERFUL EASTCOAST/WESTERN ATLANTIC STORM SUN-MON...AN AMPLIFIED ERN PAC TROF AND SHARPENING W-CNTRL NOAM RIDGE INPLACE AT THE START OF THE MEDIUM RANGE PERIOD EARLY SAT WILLSUPPORT FURTHER DEEPENING OF AN EVOLVING ERN CONUS TROF THATSHOULD REACH THE EAST COAST AROUND DAY 5 MON. UPSTREAM FLOWSHOULD TREND FLATTER WITH TIME AS ERN PAC TROF ENERGY LIFTS NEWDINTO THE WEST BY SUN-MON AND CONTINUE EWD THEREAFTER... WHILEADDITIONAL ERN PAC ENERGY WITH GENERALLY MODEST AMPLITUDECONTINUES TOWARD/INTO THE WEST. THIS LOWER AMPLITUDE WRN FLOW ISEXPECTED TO KICK OUT THE DEEP ERN TROF BY TUE-WED.OPERATIONAL MODELS AND ENSEMBLES CONTINUE TO SHOW CONSIDERABLESPREAD WITH THE TRACK OF THE SYSTEM FCST TO DEEPEN AS IT TRACKSFROM THE GULF COAST OR GULF OF MEXICO INTO THE WRN ATLC OR ALONGTHE EAST COAST. THE PAST 2-3 OPERATIONAL ECMWF RUNS HAVEINDICATED A MASSIVE...DEEP...SLOW-MOVING CYCLONE HUGGING THECAROLINA AND MID ATLANTIC COASTS THE TWO DAYS FOLLOWING CHRISTMAS. THE ECMWF AND UKMET WERE THE FIRST OF THE GLOBAL MODELS TO SWITCHFROM TRACKING THIS WAVE ALONG 40N THROUGH THE MIDWEST...TO ASUPPRESSED PATH ACROSS THE DEEP SOUTH. SINCE THIS ADJUSTMENT...THE UKMET TRENDED EVEN FARTHER SOUTH...WITH THE ECMWF LOCKING ONTOAN EVOLUTION THAT TAKES THE DEVELOPING LOW TO THE FLORIDAPANHANDLE AND THEN SHARPLY UP THE EASTERN SEABOARD. THE 06Z GFSHAS ALSO TRENDED TO A VERY SUPPRESSED SOLN ACROSS THE GULF...ADDING SUPPORT FOR SUCH A SCENARIO FOR AT LEAST THAT PART OF THEFCST. THE TRACK OF THIS SYSTEM BEYOND THE GULF REGION STILL DEPENDSHEAVILY ON SHRTWV DETAILS OF NRN STREAM FLOW... WITH WHICH MODELSSOMETIMES HAVE CONSIDERABLE DIFFICULTY UNTIL WITHIN A COUPLE DAYSOF THE VALID TIME. OF PARTICULAR NOTE THE 00Z/06Z GFS ARE ON THESHARP/WWD ELONGATED SIDE OF THE FULL GUIDANCE SPREAD WITH ENERGYOVER THE WRN GRTLKS/UPR MS VLY AS OF EARLY DAY 4 SUN. THISORIENTATION OF FLOW LIKELY PLAYS A PART IN THOSE GFS RUNS TRACKINGTHE DEEPENING WRN ATLC SFC LOW WELL OFF THE COAST. THE 00ZGEFS/ECMWF ENSEMBLE MEANS OFFER MORE SUPPORT FOR A SHARPER ANDMORE N-S ORIENTED TROF THAN RECENT GFS RUNS. WHILE THE 00Z AND12Z/21 ECMWF EVOLUTIONS ARE FAIRLY EXTREME WITH THE DEPTH OF THEMID LVL LOW THAT CLOSES OFF NEAR THE EAST COAST... THEY APPEAR ALITTLE MORE COMPATIBLE WITH ENSEMBLE MEAN IDEAS VERSUS GFS RUNS. AS THE LOW TRACKS ALONG THE EAST COAST THE 00Z ECMWF IS ON THE WRNSIDE OF THE SPREAD OF 00Z ECMWF ENSEMBLE MEMBERS AND WWD OF ALL00Z GEFS MEMBERS WHICH ARE ADMITTEDLY SOMEWHAT LOWER INRESOLUTION. WHILE THE STRONG DYNAMICS ALOFT MAY WELL SUPPORT THEOPERATIONAL ECMWF SOLN... IT IS TOO EARLY TO SUBSCRIBE FULLY TOITS FCST. A SOLN IN THE WRN HALF OF THE GUIDANCE SPREAD STILLAPPEARS REASONABLE THOUGH. AS A RESULT WILL GO WITH A BLENDCONSISTING OF 30 PCT EACH 00Z ECMWF AND 12Z/21 ECMWF RUNS WITH THEREMAINING 40 PCT OCCUPIED BY THE 00Z ECMWF ENSEMBLE MEAN.THE PREFERRED BLEND FOR THE ERN CONUS/WRN ATLC EVOLUTION TONESDOWN THE 00Z ECMWF THAT IS ON THE SHARP/AMPLIFIED SIDE OF THEENVELOPE WITH THE MID LVL TROF ENTERING THE WEST ON DAY 4 SUN. CONFIDENCE IN PARTICULARS OF ERN PAC TO PLAINS/GRTLKS FLOWDECREASES AS AMPLITUDE OF THE MEAN FLOW LIKEWISE DECREASES. BYDAY 7 WED THE MOST COMMON IDEAS OF ENSEMBLE MEANS ARE TOWARD AWEAK SHRTWV REACHING THE GRTLKS AND VICINITY... A SHRTWV TROFNEARING THE WEST COAST... AND A MODERATE TROF REACHING NWRNMEXICO. ECMWF RUNS FIT THE ENSEMBLE MEANS BETTER THAN THE 00Z/06ZGFS WHICH APPEAR SOME WHAT SLOW. EXPECT SOME LOCALLY MDT-HVY PCPNOVER CNTRL-NRN CA DURING THE FIRST HALF OF THE PERIOD WITH THELEADING TROF EJECTING INTO THE WEST. EXPECT A DRIER PERIOD ALONGTHE SRN HALF OF THE WEST COAST MON-TUE... BUT THE DAY 7 SHRTWV MAYPUSH PCPN SWD AGAIN BY NEXT WED.

[Tiburon]

thats old

That's porn.

are you guys serious with this? ur relying on 6z GFS for what, a bucking trend? the trend has ALREADY been been established. will a 0z EURO solution pan out, prob not to that extreme (although it is likely). but a compromise between the EURO and the now trending GFS towards the EURO looks pretty good at this stage. the only way i see this not affecting the major cities is if the things phases too late. but with a stc low south and further west almost every cycle run with the GFS and NAM, we are increasing the chances of an ideal phase. those that are saying things are trending in the other direction are just FLAT OUT WRONG! and im no expert, just observing and paying attention. really NOT that hard to do!

Folks, modeling does not "trend." The model is run based upon the data it has available to it at its initialization time. The 6Z GFS doesn't "know" that the 0Z EURO blew up a bomb. It doesn't even "know" that the 0Z did what it did. The more the southern stream is slowed by the modeling--because the southern stream s/w really IS being slowed by the upper air flow, the better chance it has of being caught by the northern stream s/w and phasing. The players are on the field. Let's see how it pans out, let's NOT go model-run-to-model-run suicidal, and let's let the pros and experienced amateurs describe what they're seeing and the pros and cons of each one, and what the model does that may be a bit kooky. Will we have a 951mb mega bomb 100 miles E of Lewes, DE? No. Will this thing slip off the coast around Jacksonville and vanish? No.

If it snows in your backyard, great. If it doesn't, great. You're not solving it bitching on AmericanWX either way.

[Guest someguy]

So let's pretend the GFS doesn't exist, what other guidance is supporting what the Euro is dishing out? A few of it's ens members? Maybe? I pose this question seriously.

so HPC morning extended disscussion is meaningless to you?

[mattie g]

Euro hr 144

Euro hr 168...

looks like a pretty fast jump in the last frame to me

168-144 = 24

Hours, that is. Were you expecting this thing to sit around for days on end?

[A-L-E-X]

HPC updated discussion also seems to favor Euro

This is by Rausch:

THE 00Z

GEFS/ECMWF ENSEMBLE MEANS OFFER MORE SUPPORT FOR A SHARPER AND

MORE N-S ORIENTED TROF THAN RECENT GFS RUNS. WHILE THE 00Z AND

12Z/21 ECMWF EVOLUTIONS ARE FAIRLY EXTREME WITH THE DEPTH OF THE

MID LVL LOW THAT CLOSES OFF NEAR THE EAST COAST... THEY APPEAR A

LITTLE MORE COMPATIBLE WITH ENSEMBLE MEAN IDEAS VERSUS GFS RUNS.

AS THE LOW TRACKS ALONG THE EAST COAST THE 00Z ECMWF IS ON THE WRN

SIDE OF THE SPREAD OF 00Z ECMWF ENSEMBLE MEMBERS AND WWD OF ALL

00Z GEFS MEMBERS WHICH ARE ADMITTEDLY SOMEWHAT LOWER IN

RESOLUTION. WHILE THE STRONG DYNAMICS ALOFT MAY WELL SUPPORT THE

OPERATIONAL ECMWF SOLN... IT IS TOO EARLY TO SUBSCRIBE FULLY TO

ITS FCST. A SOLN IN THE WRN HALF OF THE GUIDANCE SPREAD STILL

APPEARS REASONABLE THOUGH. AS A RESULT WILL GO WITH A BLEND

CONSISTING OF 30 PCT EACH 00Z ECMWF AND 12Z/21 ECMWF RUNS WITH THE

REMAINING 40 PCT OCCUPIED BY THE 00Z ECMWF ENSEMBLE MEAN.

[Swiscaster]

<BR>Looks like an HPC update since Dave's post a few minutes ago WHILE THE STRONG DYNAMICS ALOFT MAY WELL SUPPORT THEOPERATIONAL ECMWF SOLN... IT IS TOO EARLY TO SUBSCRIBE FULLY TO ITS FCST. A SOLN IN THE WRN HALF OF THE GUIDANCE SPREAD STILLAPPEARS REASONABLE THOUGH. AS A RESULT WILL GO WITH A BLENDCONSISTING OF 30 PCT EACH 00Z ECMWF AND 12Z/21 ECMWF RUNS WITH THEREMAINING 40 PCT OCCUPIED BY THE 00Z ECMWF ENSEMBLE MEAN.THE PREFERRED BLEND FOR THE ERN CONUS/WRN ATLC EVOLUTION TONESDOWN THE 00Z ECMWF THAT IS ON THE SHARP/AMPLIFIED SIDE OF THEENVELOPE WITH THE MID LVL TROF ENTERING THE WEST ON DAY 4 SUN. <BR>

That discussion is more reasonable than the preliminary, which basically tossed out the non-Euro operational model solutions. Wouldn't this blend result in a screwjob for most of the non-coastal areas of the Eastern Seaboard north of NC?

[Chagrin Falls]

Folks, modeling does not "trend." The model is run based upon the data it has available to it at its initialization time.

This is debated. I've seen research papers both for and against the "trend" theory.

Atmospheric numerical models often use data from previous runs, therefore they don't exist in a vacuum or bubble. Inaccurate initialization from previous runs can affect the output and verification from future runs. Some models rely on data from other models. It gets really complex and that's all I care to know about them.

Anyway, I believe models do "trend" towards a more accurate solution as time approaches 0 (initialization). That doesn't mean the trend is linear, but I do think trends exist.

[IsentropicLift]

168-144 = 24

Hours, that is. Were you expecting this thing to sit around for days on end?

My point is...the 00z euro looks like a smaller impact from NYC on NE vs the 12z run which killed everyone

[A-L-E-X]

This is debated. I've seen research papers both for and against the "trend" theory.

Atmospheric numerical models often use data from previous runs, therefore they don't exist in a vacuum or bubble. Inaccurate initialization from previous runs can affect the output and verification from future runs. Some models rely on data from other models. It gets really complex and that's all I care to know about them.

Anyway, I believe models do "trend" towards a more accurate solution as time approaches 0 (initialization). That doesn't mean the trend is linear, but I do think trends exist.

I believe in the trend scenario also-- but from a different perspective. The further away you are from an event, the more possibilities there are on the table; as you get closer to the said event, the number of possibilities slowly decrease and finally collapse to just one at time zero. This convergence can be considered a form of trending or at least give the illusion of trending. This of course doesnt take into account any initialization problems-- in which case, the "just one" at time zero (model initialization) is wrong too!

This is the basic theory behind wave collapse in quantum mechanics also.

[A-L-E-X]

My point is...the 00z euro looks like a smaller impact from NYC on NE vs the 12z run which killed everyone

qpf totals from that run would argue otherwise (1" NYC 1.5" western LI, 2-2.5" eastern LI and BOS.) Granted, this thing is highly unlikely to be worked out exactly right days in advance.

[IsentropicLift]

I don't have access to the QPF Euro maps so I probably should not have commented however just from the naked eye....the impacts looks less for that area than 12z

[Tiburon]

I believe in the trend scenario also-- but from a different perspective. The further away you are from an event, the more possibilities there are on the table; as you get closer to the said event, the number of possibilities slowly decrease and finally collapse to just one at time zero. This convergence can be considered a form of trending or at least give the illusion of trending. This of course doesnt take into account any initialization problems-- in which case, the "just one" at time zero (model initialization) is wrong too!

This is the basic theory behind wave collapse in quantum mechanics also.

Whether (pun intended) it's about modeling using previous run data (thanks Chagrin--I didn't know that) or it's about having more and more reliable information available, IMHO that's not "trending," that's being able to digest more information and limiting the number of available permutations.

[Tiburon]

I don't have access to the QPF Euro maps so I probably should not have commented however just from the naked eye....the impacts looks less for that area than 12z

You realize that even if the assertion is correct, you're splitting hairs with the difference between yesterday's 12Z EURO depiction of 2' of snow from Charlotte to Portland to the 0Z EURO's depiction of 18-24" from Charlotte to Boston?

Both runs are absolute bombs, and if verified verbatim would result in a NESIS 4 or 5 storm.

[A-L-E-X]

Whether (pun intended) it's about modeling using previous run data (thanks Chagrin--I didn't know that) or it's about having more and more reliable information available, IMHO that's not "trending," that's being able to digest more information and limiting the number of available permutations.

No, what Im thinking is ALL of those options are viable at the early stages of the game, but multiple cause and effect scenarios narrow down the possibilities as we get closer in time. IOW the future isnt determined in advance-- but is the result of convergence of multiple factors over time.

It's more convergence than trending, but we're talking about reality converging, not models converging.

[Midlo Snow Maker]

That's porn.

that has been updated was a 976 further SW but still looks good

[White_Mtn_Wx]

so HPC morning extended disscussion is meaningless to you?

so a 100 yrs of strong La Nina climo for east coast snow storms is meaningless to you?

[A-L-E-X]

so a 100 yrs of strong La Nina climo for east coast snow storms is meaningless to you?

the la nina is moderate not strong.

[Paweatherguy1]

well to me anyway it seems like the Euro is the only model that keeps the same track for more than 2 runs in a row lol

I'm not sure that is true....the GFS has had the same track now for a bunch of runs in a row, but it is unfortunately the track we don't want to see, so I think some are tending to discount it.

[aldie 22]

I'm not sure that is true....the GFS has had the same track now for a bunch of runs in a row, but it is unfortunately the track we don't want to see, so I think some are tending to discount it.

This is not true as far as the GFS someone posted the last 4 run tracks and they are all different.

[pythium]

take a look at the CIMSS from 0z has potential...............