Texas winter wx thread (2009-2010)

[Portastorm]

Don't see much change so far on this 0z GFS run for Christmas Day in Texas. For most of us it looks like a very cold, crisp day with little chance of any snow miracles.

[iorange55]

Of interest though is it does develop a swath of moisture in West Texas a day after Christmas, and as it moves east it kind of goes away, but it looks like it should be something to watch for sure. Also it looks to be a colder run.

[wxman22]

0z GFS shows what appears to be light snow the day after Christmas across west-central to east Texas...







Here you can see the upper level energy swinging through the state... It'll be interesting to see if it starts to become more aggressive with it...

[Portastorm]

Indeed iorange55, it does do that. That swath of moisture looks like it could mean some light snow for Central Texas next Sunday. This is an encouraging development!

OK, I'm off to be a better host to my holiday-time houseguests ... y'all need to keep an eye on this GFS run and post away!

[iorange55]

I imagine it will become more aggressive with it as always seems to be the case with the GFS, so let's hope it actually is picking up on something, and not a one run fluke. I'll be very interested in the GFS 06.

[Ntxw]

How dry is the air when that feature comes through? I hope it's not like the virga storm earlier in the month.

[Portastorm]

FWIW, the 0z Euro did not show anything for Christmas weekend in terms of a short-wave trough swinging through Texas and creating snow. Very different look than 0z GFS.

Edit update: I should also add that the 0z GFS is much colder looking for Christmas weekend for Tejas than the 0z Euro.

[srainhoutx]

Just an FYI, the NAM has been on a roll as of late. Just took a look at the 12Z run and there are some differences that will need to be monitored over the days ahead as compared to the GFS and the ECMWF.

[iorange55]

Just an FYI, the NAM has been on a roll as of late. Just took a look at the 12Z run and there are some differences that will need to be monitored over the days ahead as compared to the GFS and the ECMWF.

Don't give hints without explaining! lol I've been watching the nam over the past few days waiting for it to get in the timeframe the only thing I might have noticed is there is more moisture down to the south, and building down into Mexico, but I don't know. I looked at it again, and it also might look like the cold front is coming a little faster as opposed to the GFS and EURO who kind of speed the low by before the cold front passes.

[gofrogs]

What are you trying to say

[iorange55]

What are you trying to say

Nothing as of yet, but the GFS 12 is looking a little different to me through 78hrs, I'll edit with an update in a minute.


The GFS 12 looks interesting to me it looks like it's lagging the low behind, and slugging more moisture behind while speeding up the cold front a little, and if this run were correct it'd be a very very very close line of getting a decent amount of snow, or rain depending on where you live.



96hrs



We'll need to watch it, but as of right now it still looks like mostly rain, but it went back in our favor a little.

[msstateguy83]

half wake rightnow so forgive me if iam wrong lol but on the 78 hr frame looks like
by the huge temp gradent with temps shootin up to near 70 in nw tx that the front is right in
that area, which i do believe would be further east then previous runs?

[srainhoutx]

Folks, we will just have to wait and see how things unfold. There still remains some uncertainty on where the Upper Low and the Surface Low track (will the two features phase and where) as well as any shortwave disturbances behind the front. HPC addresses this in Prelim Extended Disco. What we do know is a Major Winter Storm will develop in the Pre Christmas time frame and the subtle differences will need to be watched in the days ahead. Keep an eye on the 26th -28th time frame as well.

http://wxweb.meteostar.com/models/noaap ... UMBLOOP=10

[iorange55]

Folks, we will just have to wait and see how things unfold. There still remains some uncertainty on where the Upper Low and the Surface Low track (will the two features phase and where) as well as any shortwave disturbances behind the front. HPC addresses this in Prelim Extended Disco. What we do know is a Major Winter Storm will develop in the Pre Christmas time frame and the subtle differences will need to be watched in the days ahead. Keep an eye on the 26th -28th time frame as well.

http://wxweb.meteostar.com/models/noaap ... UMBLOOP=10

Ever since whatever model that was that showed the Disturbance no other model has really shown it in the 26-28th beginning to wonder about that.

[cperez1594]

Brownsville AFD sounding off...

.LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...COMPLEX WEATHER
PATTERN SHAPING UP FOR THE LATER HALF OF THE LONG TERM FORECAST
WITH LOW CONFIDENCE IN THE OVERALL EVOLUTION OF MODEL SOLUTIONS.
WEST COAST TROUGH DEEPENS TUESDAY WITH A POTENT UPPER LOW TO
DEVELOP OVER THE SOUTHERN ROCKIES AND SOUTHERN PLAINS WEDNESDAY.
MAIN WEATHER ON TUESDAY WILL BE STRONG SOUTH WINDS AND WARM
TEMPERATURES ABOUT 10 DEGREES ABOVE SEASONAL AVERAGES. THEN A COLD
FRONT SWEEPS THROUGH DEEP SOUTH TEXAS LATE WEDNESDAY BUT GUIDANCE
SUGGEST THE COLDEST AIR TO REMAIN NORTH OF THE VALLEY AS UPPER LOW
BECOMES MORE WESTERLY THEN NORTHWEST. FORECAST SHOWS A STEADY
FALLING OF TEMPERATURES THROUGH FRIDAY AS LARGE TROUGH GETS CARVED
OUT OVER THE LOWER 48. HOW COOL OR COLD IT GETS IS STILL IN
QUESTION...BUT EXPECT TEMPERATURES TO SETTLE APPROXIMATELY 5 TO 10
DEGREES BELOW NORMAL ON CHRISTMAS DAY. AS FOR SENSIBLE WEATHER SEA
FOG COULD DEVELOP MONDAY NIGHT INTO TUESDAY MORNING BUT LOW LEVEL
JET MIGHT BE TO STRONG FOR FOG DEVELOPMENT SO WILL LEAVE OUT OF
FORECAST FOR NOW. MOISTURE FIELDS ARE NOT THAT IMPRESSIVE IN
ADVANCE OF WEDNESDAYS FRONT BUT LOW LEVEL MOISTURE MIGHT BE
SUFFICIENT TO PRODUCE ISOLATED SHOWERS SO WILL LEAVE THE SLIGHT
CHANCES IN FOR WEDNESDAY.

LATEST MODEL RUNS ARE NOW INDICATING A MUCH STRONG FRONT TO PUSH
WELL SOUTH OF THE REGION SATURDAY WITH MODIFIED ARCTIC AIR MOVING
INTO NORTH TEXAS. IF THIS SCENARIO DOES DEVELOP DEEP SOUTH TEXAS
COULD EXPERIENCE THE COLDEST TEMPERATURES OF THE SEASON BOTH
SATURDAY AND SUNDAY WITH POSSIBLE FREEZING TEMPERATURES ACROSS ALL
AREAS BY SUNDAY MORNING. PRECIPITATION OUTLOOK LOOKS EVEN MORE
COMPLEX AND IF PRECIP DOES DEVELOP THERE IS AN OUTSIDE CHANCE OF
FREEZING DRIZZLE ACROSS OUR NORTHERN ZONES. LETS HOPE NOT.

[srainhoutx]

Here is a post just made by wxman57 in the "local Forum" just after I posted here on S2k. Some might find it interesting.

As for next week, I did see one change in the 00Z GFS run. It now shows that if/when that shortwave passes the 26th/27th that there will, indeed, be plenty of moisture to work with. I just plotted the projected vertical profile from the 00Z GFS valid 6pm on the 26th. See below. Shows the atmosphere sub-freezing all the way down to the surface AND enough moisture for precip.

But it's just one run of the GFS, and the Euro backed away from that solution on the 00Z run. 12Z run coming in now.

http://myweb.cableone.net/nolasue/GFS3.gif

[Portastorm]

One thing I have noticed is by 12z Friday, the new 12z GFS run has upper level energy more compacted in the Northern Plains as compared to the 0z run which had more of an elongated west-east area of upper level energy. Consequently by 0z Saturday ... you will see a much more direct plunge of Polar air, almost a north-to-south flow at the 500mb level. All in all, that should provide colder air for the Southern Plains and Texas by Saturday and ensure the air column is deeper with cold air (i.e. better shot of snow with any moisture as compared to sleet or freezing rain).

Edit update: But ironically enough, the same mechanism that would ensure a better shot at snow is the same mechanism that also would ensure a drier airmass, plunging the front deeper in the Gulf and precluding any near-shore surface low development which could sling some beautiful moisture into that deep-freeze airmass above us!

Edit update II: I shouldn't have missed this but there definitely is more moisture along the Red River and even into the northern 'burbs of Dallas around Christmas Eve per this 12z run. That is a nice "trend" for you folks up north and could mean a better shot at flurries or even some light snow. Don't forget that the GFS always is too slow on Arctic/Polar frontal passages.

[CYCLONE MIKE]

In regards to the discussion about the coldest air coming down after x-mas for the south, our yesterdays afd mentioned the same thing. Basically said if the forecast verifys,and seems pretty confident in them, the flood gates would be opened up allowing the coldest air so far this season to come down which would lead to hard freezes for a lot of our areas. Here is our brief early morning long term afd as well...hmmm subtropical jet remaining very active? More gulf lows by chance with the artic air?


LONG TERM...
THE POLAR JET AND SYNOPTIC PATTERN WILL BE INTENSELY AMPLIFIED BY
THURSDAY. THIS WILL SIMPLY OPEN THE DOOR TO THE POLAR REGIONS
BRINGING SOME OF THE COLDEST AIR OF THE SEASON BY THE END OF THE
WEEK. THE SUBTROPICAL JET ALSO REMAINS VERY ACTIVE DURING THAT
PERIOD AS WELL.

[msstateguy83]

this is from koco tv 5 out of okc pushing the snow line much further east now

[iorange55]

Lets hope this trend continues I almost don't want to look at the GFS 18 when it comes out cause I'm sure it'll go back to nothing for us, but who knows. Should be interesting to watch, at least there is chance.




I've gotta go to a Christmas party thing hopefully there is some nice things to come back too.