Texas Winter 2012-2013

[CaptinCrunch]

Why do I continue to torture myself with long range models that never come true!!! And why is Larry Cosgrove mentioning a major after Christmas storm 25-27 that the models have pretty much done away with for OK/TX?

Larry has watched 'The Day After Tommrow" 1 to many times over the summer!!!

[iorange55]

Why do I continue to torture myself with long range models that never come true!!! And why is Larry Cosgrove mentioning a major after Christmas storm 25-27 that the models have pretty much done away with for OK/TX?

As you were told a day or two ago when you asked a similar question; the models always flip-flop this far out. They haven't "done away" with the storm, they're just not sure what to do with it yet. It could go north (not likely), it could hit north-texas/oklahoma...or it could go even further south. There is also the question of strength, and whether it'll open up or not.

Just chill out, man! We'll know something very soon. Right now just get ready for the cold!

[Snowman67]

Let's see where the models take us today, I have a feeling they might start going back to what they were seeing a few days ago.

If I'm not mistaken, didn't the models back off of Snowpocalypse 2010 a few days preceding the actual event, and then a day or two before went back to the original line of thinking? I know I'm generalizing all of the models here, but I feel like there is somewhat of an expand/contract process that these models go through leading up to a major event. For some reason that comes to mind.

Or, maybe I'm just grasping at my wishcast.

You are not mistaken. Just a couple of days out from the event, what was predicted was nowhere near the amount of snowfall that occurred.

[Tireman4]

Why do I continue to torture myself with long range models that never come true!!! And why is Larry Cosgrove mentioning a major after Christmas storm 25-27 that the models have pretty much done away with for OK/TX?

As you were told a day or two ago when you asked a similar question; the models always flip-flop this far out. They haven't "done away" with the storm, they're just not sure what to do with it yet. It could go north (not likely), it could hit north-texas/oklahoma...or it could go even further south. There is also the question of strength, and whether it'll open up or not.

Just chill out, man! We'll know something very soon. Right now just get ready for the cold!

Great advice. Spot on. We have been watching models for like...forever...and I am not even thinking of serious looking until Sunday at the earliest.

[CaptinCrunch]

Let's see where the models take us today, I have a feeling they might start going back to what they were seeing a few days ago.

If I'm not mistaken, didn't the models back off of Snowpocalypse 2010 a few days preceding the actual event, and then a day or two before went back to the original line of thinking? I know I'm generalizing all of the models here, but I feel like there is somewhat of an expand/contract process that these models go through leading up to a major event. For some reason that comes to mind.

Or, maybe I'm just grasping at my wishcast.

You are not mistaken. Just a couple of days out from the event, what was predicted was nowhere near the amount of snowfall that occurred.

The Snowpocalypse that dumped 12" across DFW was a model feature as far as 10 days out, then dropped out the map till a 3 days out. Even then the models still showed it to be a very progressive wave which it was as it moved out of New Mexico, however what the models didn't count on was it slowing to a crawl as it got to Abline and from there out history was recorded.

By Sunday we will have a good idea of whats going to happen and even then it can still change....LOL

[gpsnowman]

Larry Cosgrove did mention over a week ago at the end of one his write ups that the end of the month Texas could have some long lasting cold. I would say he is spot on. He also mentioned possible snow and ice north of I-20 several days ago around Christmas before anyone was talking about it. He could be spot on I think. He was onto something then without getting to detailed.

[SaskatchewanScreamer]

After looking at your very energetic Santa avatar Tireman I really do think you should head up here and push/drag/cajole the cold back to your State (just lasso some moisture on your way back down and you've got it made).

You can leave your annoying 70's here! edited to say we will suffer through it for you!

[Ntxw]

12z gfs is back north now with the cutoff negative tilt Oklahoma blizzard. That's three straight runs with three different outcomes.

[iorange55]

12z gfs is back north now with the cutoff negative tilt Oklahoma blizzard. That's three straight runs with three different outcomes.

Yup...just a prime example of the flip flopping. It does something completely different with the storm than the 0z run. This will likely continue 'til Friday.

[wxman57]

GFS definitely trended north with the storm system next week and is weaker/faster with the upper low/trof. No snow for TX as per the 12Z GFS. I certainly expect future model changes as to next week's event. One thing to watch is if the current Euro/GFS agreement continues for a few days.

[GRAYSONCO.WX]

GFS definitely trended north with the storm system next week and is weaker/faster with the upper low/trof. No snow for TX as per the 12Z GFS. I certainly expect future model changes as to next week's event. One thing to watch is if the current Euro/GFS agreement continues for a few days.

The 12Z GFS is showing snow for northern Texas. I would say from about from Denton to McKinney, northward to the Red River.
EDIT: Per AccuPro GFS maps.

[iorange55]

CMC is somewhat similar to the 12z GFS, though, it looks like it might be stronger/colder. If the CMC were to verify, Oklahoma and to the north would get some nice snowfall.

North Texas would pick up some flurries...maybe on the back end. Things will change, though! I suspect a shift a little further to the south...

As others have said, it might be similar to the "blizzard" of Christmas '09.

[Ntxw]

One thing the models (except GFS) have been trending is faster and colder with the air mass. GFS does go faster but is quick to move it out. The near 1050hp's have trended back on the models in Canada.

[iorange55]

12z Euro appears to be digging a little more? And it looks to be faster with the system through 144hrs.

Edit:

Mighty cold!

[Ntxw]

12z Euro appears to be digging a little more? And it looks to be faster with the system through 144hrs.

Edit:

Yeah it's giving parts of north Texas and Oklahoma snow

[txtiff]

12z Euro appears to be digging a little more? And it looks to be faster with the system through 144hrs.

Edit:

Yeah it's giving parts of north Texas and Oklahoma snow

Is it good or bad for snow that it shows to be faster with the system?

[Portastorm]

12z Euro appears to be digging a little more? And it looks to be faster with the system through 144hrs.

Edit:

Yeah it's giving parts of north Texas and Oklahoma snow

Is it good or bad for snow that it shows to be faster with the system?

Not easily answerable. If the upper level low stays intact and the trough in which the ULL is at the base of is negatively tilted, speed would be irrelevant. If you're underneath that column of air, your chances of snow would be decent. However, if the system gets sheared out or the ULL opens up and is not a compact system ... then a slower progression would generally favor a better chance of frozen precip.

Keep in mind that the computer models almost always underestimate the speed of Arctic/polar air.

[Ntxw]

^ What Portastorm said. The reason we have seen the system shift wildly is because they don't know where to put the polar/arctic front. Surface low pressure always rides up the leading edge and the lagging 5h low will pull moisture back if it is compact and strong.

To get a strong system you want it stacked, so the 5h low and the surface low are nearby. If the cold air is too fast and plows then the surface low will race ahead and you get the 0z GFS solution, cold and dry. If the cold air is slower, everything just happens further north near the boundary.

[wxman57]

12z Euro appears to be digging a little more? And it looks to be faster with the system through 144hrs.

Edit:

Yeah it's giving parts of north Texas and Oklahoma snow

The high-res Euro (every 3 hrs) is coming in now on my workstation. I'll check to see where it is predicting snow. It's in through 18Z the 24th now. I'm also plotting the 500mb heights from the 00Z Euro along with the 12Z Euro so that I can compare at each time intervals. Not a lot of difference through 18Z the 24th. Ah, the next few panels just came in. Definite difference indicated by late the 24th. 12Z is slower and deeper with the upper trof.

I don't see that the 12Z GFS is forecasting any snow for north TX, as was mentioned above. Maps at twister.com show the southern extent down to about OKC:

[Ntxw]

Thanks for the data Wxman57. I'm not sure where Graysonco.wx saw the snow on the GFS either, you are right it doesn't have much even for Oklahoma.