TX Winter Wx Threat # 9--- Another Arctic Outbreak?

[Portastorm]

lol. This local forecast is really quite laughable:

http://images.ibsys.com/hou/images/weat ... 40x480.jpg

Many people probably expect next weekend to be a "nice" one when they look at something like this. Temps. in the 60s with partly sunny skies sounds pretty good.

Too bad that forecast will bust badly..

I hate to say this EWG ... but it could be right. What if the true arctic air doesn't impact the southern half of the state until Saturday night or Sunday? It is possible.

[cctxhurricanewatcher]

lol. This local forecast is really quite laughable:

http://images.ibsys.com/hou/images/weat ... 40x480.jpg

Many people probably expect next weekend to be a "nice" one when they look at something like this. Temps. in the 60s with partly sunny skies sounds pretty good.

Too bad that forecast will bust badly..

That's not the only forecast that might bust badly. The TV mets here in Corpus are doing the same and one went from saying we might get some Arctic fronts starting Saturday to now (yesterday) saying nothing about it. At the very least they could say the models are here and there about the "potential" of a prolonged cold weather event that might bring in some of the coldest temps in years.

But what Portastorm just noted could be one reason some of the TV Mets might be holding back completely.

[aggiecutter]

Portastorm, might be right about the temperatures. Depending on the timing and speed of the front, temperatures at a given hour could range from the upper 50's to the lower 60's in south-central Texas to the upper 20's in Dallas to lower teens in Oklahoma City. I've seen that happen before.

[Extremeweatherguy]

lol. This local forecast is really quite laughable:

http://images.ibsys.com/hou/images/weat ... 40x480.jpg

Many people probably expect next weekend to be a "nice" one when they look at something like this. Temps. in the 60s with partly sunny skies sounds pretty good.

Too bad that forecast will bust badly..

I hate to say this EWG ... but it could be right. What if the true arctic air doesn't impact the southern half of the state until Saturday night or Sunday? It is possible.

Sure, there is a chance, but it is probably a slim one at this point.

From what I have seen today, it looks like the leading edge of the cold should arrive sometime between late Thursday and early Saturday for us and it should continue to go downhill from there.

I am just having a hard time believing we will see this big warmup into the 60s with lows near 50 and sunshine late next week and next weekend. Even if the front was still stuck in north Texas at that point, I would at least expect clouds and a chance of rain. That 0% rain chance and sunshine for Saturday just seems a bit far-fetched.

I guess we will see, but at this point I still feel that next Saturday will be a lot cooler and wetter than shown in that forecast above..



ALSO (8:48pm): The thing that really scares me about that forecast is I think that the 60s with sunshine prediction may be what they think is coming BEHIND the front (which is what the NWS is currently calling for here in Houston too). If that is the case, then it really will be busting big time. I will try to catch the 10pm news tonight to see if that is the case.

[aggiecutter]

BTW, the first of the 3 feeder shots is well on its way. Texarkana is forecasted to go into the 20's 3 times this week before the coldest shot arrives next weekend.

Current Temperatures:
http://twister.sbs.ohio-state.edu/surface/ustemp.gif

[ETXHAMXYL]

On wfaa's 6 oclock weather STeve McCauley who usually gets very giddy, mentioned the McFarland effect but when the temps for the week came up with something falling on Tues-Friday he passed right over it never saying rain or frozen just it was too early to tell but the coldest would be coming on Sunday with a high of 41.
I am shocked since he just shouts any frozen stuff from the mountain tops if there is just a slight chance. If you were not looking at the white stuff falling on the graphics you wouldn't have even known there is a chance. It was hard to tell if it was cold rain, sleet, snow or a mix by looking at the graphics.
Someone must have told him to lay off or tone it down with any froz. stuff in the future. HIghs were in the 40's but he wasn't as excited like usual.
Going to try and catch him at 10 and see if he does the same avoidance.

[Extremeweatherguy]

In the shorter term, a front (that is actually pretty strong) is almost to Houston tonight...

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
800 PM CST SAT JAN 27 2007

.DISCUSSION...MSAS SURFACE ANALYSIS INDICATED THE COLD FRONT
MOVING INTO THE EXTREME NORTHERN PORTIONS OF THE CWA THIS EVENING.
SATELLITE AND RADAR IMAGES CONTINUE TO INDICATE ISOLATED SHOWERS
MOVING ACROSS SOUTHEAST PORTIONS OF SOUTHEAST TEXAS. WINDS ARE
EXPECTED TO SHIFT TO THE NORTH AND INCREASE BEFORE MIDNIGHT ACROSS
MOST OF THE AREA AS THE FRONT MOVES SOUTHWARD. TEMPERATURES WILL
FALL AT LEAST 10 DEGREES BEHIND THE FRONT. EXPECT LOWS TONIGHT TO
FALL INTO THE 30S ACROSS NORTHERN AND CENTRAL PORTIONS OF THE CWA
WITH LOWS IN THE 40S TOWARDS THE COAST. ONLY MINOR CHANGES TO THE
GRIDS/ZONES ARE NEEDED AT THIS TIME.

This front will make tomorrow a chilly one for sure (compared to averages) with highs only in the upper 40s to lower 50s and a freeze tomorrow night for many!

[aggiecutter]

I think the high on Sunday in Dallas will be closer to 21 than 41. The NWS forecast has a high in Dallas on Tuesday of 41, and that air mass wont be nearly as cold as the one coming this weekend.

[Portastorm]

Heck, the 0z run of the NAM is pretty cold at 84 hrs out. Run has the zero 850mb line running east-west across Texas about mid-state (crossing Waco).

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _084.shtml

[double D]

Yeah and the 0c 2 meter line hangs around central Texas too. That sure looks a lot diffreent than the GFS at the same time period.

[wall_cloud]

I think the high on Sunday in Dallas will be closer to 21 than 41. The NWS forecast has a high in Dallas on Tuesday of 41, and that air mass wont be nearly as cold as the one coming this weekend.

Its all good and well to speculate on when the cold air will be in place. The problem is assigning your name to a forecast 20 degrees below guidance and having the cold front slow by one day. While you might have had a good forecast with timing differences, your verification scores just went in the toilet. You have to play it at least somewhat conservative until you have a better handle on timing. And day 7 really isn't the time to go gang-busters in my opinion unless you are certain. Speculating is easy. You can just say you were a bit off and move on. Sending out a forecast to the world with your name on it is quite different. Just my 2 cents.

[aggiecutter]

The 0z GFS looks to have a good idea of what will eventually happen next weekend into next week. However, its continuity from 12hr time frame to 12hr time frame does leave you scratching your head. Having said that, it seems to have a reasonable solution as far as the upper air pattern and surface output is concerned. At its coldest, it has surface temperatures at -10C(14F) into the Red River Valley of Northern Texas. Of course, this is probably a little under done, and temperatures will probably be colder than that.

0z GFS:
http://www.nco.ncep.noaa.gov/pmb/nwprod ... /fpc.shtml

[Portastorm]

I'm beginning to think that the much-ballyhooed Arctic express is going to resemble -- for most of us -- an unimpressive Southern Pacific freight train.

The GFS' consistent difficulty in handling the surface temps and even, at times, the 850mb flow is well documented. However, the last 3-4 runs show less and less of an effect of Arctic air on Texas. While this model has its problems, it can't be so wrong every run for so many times, can it?

The European for the last several runs shows the bulk of the blast centered more towards the Great Lakes and Southeast U.S. with Texas receiving a glancing blow at best.

And this morning's NCEP ensembles are really watering down any possible major cold blast.

http://www.cdc.noaa.gov/map/images/ens/ ... ation.html

I dunno gang ... at some point we have to separate fantasy from fact. And to my eyes, the facts say its looking more and more like all we're going to get next weekend is a typical winter cold front.

[Tamora]

I think the high on Sunday in Dallas will be closer to 21 than 41. The NWS forecast has a high in Dallas on Tuesday of 41, and that air mass wont be nearly as cold as the one coming this weekend.

I think it was Sat he said would be 41. He said if he does the math one way, we get the McFarland Signature and our temps will be MUCH colder, but it he does it another way, it won't be so cold, cold, but not freezing. I am assuming this is coming from the flip floping of the systems?

[Furious George]

http://weather.cod.edu/forecast/loop.ecmwf850t.html

Notice the kicking of the cold air to the East from day 6 to day 7. This may save TX (at least SE TX) from the brutal cold.

But at the same time look at where the center of the arctic air is (and the Magnitude!). Just north of the US border - impressive.

[double D]

I'm beginning to think that the much-ballyhooed Arctic express is going to resemble -- for most of us -- an unimpressive Southern Pacific freight train.

The GFS' consistent difficulty in handling the surface temps and even, at times, the 850mb flow is well documented. However, the last 3-4 runs show less and less of an effect of Arctic air on Texas. While this model has its problems, it can't be so wrong every run for so many times, can it?

The European for the last several runs shows the bulk of the blast centered more towards the Great Lakes and Southeast U.S. with Texas receiving a glancing blow at best.

And this morning's NCEP ensembles are really watering down any possible major cold blast.

http://www.cdc.noaa.gov/map/images/ens/ ... ation.html

I dunno gang ... at some point we have to separate fantasy from fact. And to my eyes, the facts say its looking more and more like all we're going to get next weekend is a typical winter cold front.

You might just be right about that Portastorm, but remember the event is still a week away and the models could easily flip to a colder solution for Texas. Remember just a few days ago, the GFS was showing the -10c line well into central Texas.

What I don't understand is that if we are supposed to have a north to northwest flow, then why would the brunt of the cold air go east?

[Extremeweatherguy]

I have become very unimpressed with Houston's AFDs lately. Austin is doing a much better job this time around...

Here is Austin's AFD (the part concerning next weekend):

THIS IS GENERALLY A LOW CONFIDENCE
FORECAST BEYOND 132H GIVEN THE POORLY MODELED ARCTIC AIRMASS
ASSOCIATED WITH THE POLAR VORTEX FORECAST BY THE MEDIUM RANGE
MODEL SUITE TO BE OVER SOUTH CENTRAL CANADA BY 168H. ALTHOUGH THE
FRONT ON FRIDAY MAY JUST BRING A SMALL...MODIFIED PIECE OF THE
ARCTIC AIRMASS...A MUCH COLDER CHUNK MAY SLIDE ACROSS OUR AREA
SOMETIME NEXT WEEKEND.

And then here is Houston's AFD (the part concerning next weekend):

500 MB FLOW REMAINS OUT OF THE SOUTHWEST THROUGH FRIDAY. LOW LEVEL
MOISTURE REMAINS IN PLACE SO WILL KEEP A CHANCE OF SHOWERS FOR
WEDNESDAY. DYNAMICS LOOK MORE IMPRESSIVE ON THURSDAY AND RAIN
CHANCES WILL BE HIGH. THINGS SHOULD BEGIN TO DRY OUT BY NEXT
WEEKEND AS A BROAD UPPER LEVEL TROUGH PUSHES EAST AND A W-NW FLOW
DEVELOPS.

BTW, here is a look at the regional comparison of high temperatures forecasted on Saturday...

Houston = 61
Beaumont = 55
Austin = 53
Victoria = 60
Waco = 47
Lufkin = 57

As you can see, Houston is clearly the warmest right now in the forecast. In fact, they are actually going above the guidance numbers. What's up with that?

[aggiecutter]

I just looked at the 0z EURO and it really digs the trough into the central part of the country-deep into Texas- on Saturday and Sunday. I don't think the next ice age is coming, but I think temperatures on those two days, maybe even into Monday, could be 20 or so below normal, particularly across the northern third of the state.

[Portastorm]

12z GFS coming in now ... check this out at 90hrs:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _090.shtml

The 850mb flow is almost due north to south ... and it appears to be funneling arctic air down the leeside of the Rockies. This is the COLDEST and fastest scenario I have seen yet.

Talk about flip-flopping ... sheesh!

EDIT UPDATE: The link below is the model at 120 hrs, followed by the 132hr scenario:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _120.shtml

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _132.shtml

The interesting thing here is the model looks quite plausible up until 120 hrs and then it gets silly with the surface temps representation. So in this case, the GFS looks somewhat trustworthy up until 5 days out and then after that .... forgeddaboudit.

This run has me re-thinking my post of just an hour ago. This run looks real cold with a possibility of wintry precip in some parts of Texas, especially north Texas.

[CaptinCrunch]

OK, we got the arctic cold on the way now lets turn our heads and look to the gulf or baja CA for the upper low so we can make some good use of this cold air.