12Z Model runs Christmas Eve 2010

[wxmeddler]

I think it's pretty pathetic that it's 2010 and our models can't even get the CURRENT conditions right!

Assuming the RUC initalised right. I can't tell any significant mesoscale difference in the 500 vort/height between the 13z ruc and the 12z NAM + 12z GFS. The one thing I can point out is the increased vorticity in the upper plains low in the NAM vs the GFS. But I only think that is because of the grid size difference between the two.I'd still trust the HPC though.

[Guest someguy]

THE SPECIFIC PREDICTIONS BY ALL DETERMINISTIC GUIDANCE ARE IN QUESTION...WITH

THE RECOMMENDATION TO FOLLOW CONTINUITY...WITH THE FINAL OUTCOME

MOST BELIEVED TO LIE BETWEEN THE 06Z GFS AND 00Z ECMWF...WITH ALL

ENSEMBLE GUIDANCE INCLUDING THE SREF MEAN/GEFS MEAN/ECMWF ENSEMBLE

MEAN ALSO CONSIDERED USEFUL TO ADDRESS THE CONTINUED UNCERTAINTY

so does this mean the GFS ens at 12z are "OK"?

[SACRUS]

THE SPECIFIC PREDICTIONS BY ALL DETERMINISTIC GUIDANCE ARE IN QUESTION...WITH

THE RECOMMENDATION TO FOLLOW CONTINUITY...WITH THE FINAL OUTCOME

MOST BELIEVED TO LIE BETWEEN THE 06Z GFS AND 00Z ECMWF...WITH ALL

ENSEMBLE GUIDANCE INCLUDING THE SREF MEAN/GEFS MEAN/ECMWF ENSEMBLE

MEAN ALSO CONSIDERED USEFUL TO ADDRESS THE CONTINUED UNCERTAINTY

so does this mean the GFS ens at 12z are "OK"?

suspect they mean 00z/06z.

[Guest someguy]

The statement says that the GEFS was still considered useful. I imagine it was impacted by the errors too, eh?

yes that is how I read what HPC said

[Clinch Leatherwood]

So that's it... The past hour was bull****... we all are still set to get flurries...

In the post mortem I'm thinking they find this was going on for more than just this run. They may not have caught it.

[RUNNAWAYICEBERG]

noted....thanks!

back on topic somewhat. latest satellite imagery has the low just north of the TX/MX border with the trough oriented SW to NE, maybe more like WSW to ENE. looks like the back side is receiving energy, highs clouds popping up on a line from TX to ARK. another band in MO. wish i knew how to post map, if thats within the rules. but the sat imagery looks good to me, my .02....

[Dcwx]

Just WOW with all of this morning's events.

At least this storm will go down historically for its faulty forecasting. We can all learn a lot from this event...

I am not understanding how the ensembles can still be legitimate if they run off the same data as the OP. Sounds like HPC might be doing this as a precaution...

[Analog96]

yes that is how I read what HPC said

Sounds like they don't know what to believe right now.

[SnowGoose69]

what i gather from the HPC is air on the side of caution... they said those errors MIGHT have impacted the forecast... they did not say they definitively did... I'm not going to pass any judgement until the 00Z runs tonight.

based on the 18Z ruc compared to the 6 hr depiction on the 12Z GFS if anything i#d say it was too weak with the norhtern shortwave and too fart NE with the TX shortwave.

Its impossible with the number of things going into this setup or ANY setup for that matter we can know if and how it impacted it...for all we know maybe the GFS did not come far enough west because of the errors!

[usedtobe]

I thought the same thing, but I'm not too up on exactly what goes into the ensemble members or how they are generated.

Yes they are and they are run at lower resolution. It's interesting that the 09Z sref still are well out to sea with the low. They also vary the initial conditions and the physics and have higher resolution than the gefs system and score better in the time range we're dealing with. Here's their surface low plot. The spaghetti diagram indicates one meber like the 12Z gfs. The bottom panel is the mean. I'm not saying the gfs is wrong but still think it is on the left hand side of possible solutions. That said, I think new england has a good shot at a major storm. Down in DC and PHL, I think the deck is still stacked against us. A westward jog of the euro would certainly sway my opinion a bit but until it does, I'd still go with a solution more like the 00Z euro.

[Clinch Leatherwood]

THE SPECIFIC PREDICTIONS BY ALL DETERMINISTIC GUIDANCE ARE IN QUESTION...WITH

THE RECOMMENDATION TO FOLLOW CONTINUITY...WITH THE FINAL OUTCOME

MOST BELIEVED TO LIE BETWEEN THE 06Z GFS AND 00Z ECMWF...WITH ALL

ENSEMBLE GUIDANCE INCLUDING THE SREF MEAN/GEFS MEAN/ECMWF ENSEMBLE

MEAN ALSO CONSIDERED USEFUL TO ADDRESS THE CONTINUED UNCERTAINTY

so does this mean the GFS ens at 12z are "OK"?

I'm 99% sure they are effected too as they are as another poster said, run around the same points. So if the starting point is wrong,even though it throws some variations in, they will still be negatively impacted.

[Amped]

QUANTITIES...INCLUDING HEIGHT/VORTICITY FIELDS/RH...ARE EVIDENT IN

BOTH THE 12Z NAM/GFS WITH SMALL BUT LIKELY SIGNIFICANT SHORTWAVE

TROUGHS OVER SOUTH DAKOTA/NEBRASKA ALONG WITH

SASKATCHEWAN/MANITOBA...WITH THESE AREAS ALSO NOT PARTICULARLY

RESOLVED OR PREDICTED WELL BY THE 00Z ECMWF. THUS...THE SPECIFIC

PREDICTIONS BY ALL DETERMINISTIC GUIDANCE ARE IN QUESTION...WITH

THE RECOMMENDATION TO FOLLOW CONTINUITY...WITH THE FINAL OUTCOME

MOST BELIEVED TO LIE BETWEEN THE 06Z GFS AND 00Z ECMWF...WITH ALL

ENSEMBLE GUIDANCE INCLUDING THE SREF MEAN/GEFS MEAN/ECMWF ENSEMBLE

MEAN ALSO CONSIDERED USEFUL TO ADDRESS THE CONTINUED UNCERTAINTY.

THIS APPROACH DISREGARDS THE SUBSTANTIALLY DEEPER AND WESTWARD

SHIFT OF THE 12Z GFS REGARDING THE POWERFUL LOW TRACKING UP THE

EASTERN SEABOARD...AND TO A LESSER EXTENT THE 12Z NAM WHICH LIES

NEAR THE FAST EDGE OF THE GUIDANCE WITH THE DEVELOPING LOW.

HPC basically says throw this run out, in more polite terms.

[SnowGoose69]

The JMA drank the same koolade the GFS did...

http://grib2.com/jma/CONUS_JMA_1000-500_SLPTHKPRP_72HR.gif

[RUNNAWAYICEBERG]

very nice moisture plum from GOM into TX. lots of energy into this thing, cant imagine this not affecting SOMEONE along the EC. it bears watching, regardless if there were errors with the 12z package.

[Bluescat1]

http://www.rap.ucar.edu/weather/satellite/displaySat.php?region=US&itype=wv&size=large&endDate=20101224&endTime=-1&duration=6

[Jefflaw77]

So what's the deal here?? Are we all just waiting for the Euro?? But will it have the same "problem's" as to GFS b/c it uses the same data??? I am so confused here..

[KEITH L.I]

The JMA drank the same koolade the GFS did...

http://grib2.com/jma...THKPRP_72HR.gif

yep a big hit..did this have errors too?..also why is every single GFS ensemble showing a hit..if they give them different information

[RUNNAWAYICEBERG]

http://www.rap.ucar....e=-1&duration=6

there it is, thank you sir....much better site, easier to link.

[Dcwx]

Can any professional met give any guidance on how the current map compares to the model runs from last night?

[RIC Airport]

Where are the individual GFS ensemble members? Can someone post or link?

[sn0w]

This setup is insane...how often is it that it is unknown in some places 48 hours or even less from the event whether or not they will see a foot plus of snow or receive not even a flake. Crazy. When does the Euro get crankin?

[ptb127]

What is causing this shift west in the models? Is it right? And can it continue to shift to the west?

[gil888]

gotta love the drama with this storm. Yes, no, yes, no, yes and then sorry its a model error! One of my favorites in recent memory.

[usedtobe]

Yes we are waiting for the EURO to put the nail in the coffin and to show the GFS drank too much Egg Nog today....

I'd also look clsely at teh 15Z sref guidance as it's in the time range where it should do OK. I'm not sure exactly when it come in.

[Bob Chill]

http://www.rap.ucar....e=-1&duration=6

Doesn't look like the phase is going to time right for the MA.

[CheesyPoofs]

I'd also look clsely at teh 15Z sref guidance as it's in the time range where it should do OK. I'm not sure exactly when it come in.

Wes, it comes in between 2:35-2:45 on NCEP and the individual members come out shortly after on the PSU ewall site.

[Amped]

Sounds like they don't know what to believe right now.

People are disregarding HPC's "disregard" statement. Still 20 minutes later.

My advice for N00bs. Read these before posting http://www.hpc.ncep.noaa.gov/html/discuss.shtml

[mike2010]

man...the forums are loading slow.

How soon before the ECM initializes...a few minutes hopefully ?

[chris87]

There is not a problem with the data but with how the assimilation system which produces the initial fields for the nam and gfs used that data to produce an initial analysis.

Unfortunately the forecaster is assuming there may be problems BC the euro didn't resolve the same features in its 0z run. So I assume they are comparing the 12 hour forecast from last notes euro with the analysis fields for the 12z nam and gfs....I haven't seen anything about bad data.

[Midlo Snow Maker]

hr 36 precip now into va from roa to ric to orf was not a 0z