Texas Winter Weather Thread #3 - GFS showing cold christmas

[Extremeweatherguy]

BTW, the 6Z GFS continues the wintery trend for Christmas:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _180.shtml
^^Christmas Eve^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _204.shtml
^^Christmas Day^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _216.shtml
^^Christmas night (WOW!)^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _228.shtml
^^December 26th^^

I am actually quite surprised to see this stick around for another run. We will now have to see if the 12Z shows the same thing (let's hope it does!).

[aggiecutter]

The morning Ensembles continue to show a trough in the central plains Christmas week and a cutoff in the Big Bend area of Texas. The Ensembles have been consistent with the central plains trough for over a week, so I think it's safe to say that it'll at least be cold Christmas week. However, the cutoff and its eventual track will be interesting to follow as this is a new player on the field that wasn't previously there. Since this is still a little over a week away, I wouldn't get too excited about the prospect of winter weather just yet. The thing that gives me some confidence is the fact that the Ensembles have picked up on it this far out.

The morning Ensembles 12-17-06:
http://www.cdc.noaa.gov/map/images/ens/ ... times.html

[wxman22]

Do ya'll think we can officely call this a BEAR WATCH.....?

[Burn1]

10-Day Fitness Forecast for
Houston, TX



Forecast Conditions High/Low °F Precip.
Chance Fitness Comfort Precipitation High Temperatures Low Temperatures
Today
Dec 17 Mostly Sunny
77°/60° 0%
9 Comfortable



Mon
Dec 18 Partly Cloudy
77°/61° 10%
9 Comfortable



Tue
Dec 19 Few Showers
76°/63° 30%
7 Moderate

Don't let Rain Ruin Your Workout

Wed
Dec 20 Showers
71°/59° 40%
8 Comfortable



Thu
Dec 21 Showers
70°/53° 40%
7 Moderate



Fri
Dec 22 AM Clouds / PM Sun
67°/47° 10%
8 Comfortable



Sat
Dec 23 Partly Cloudy
67°/46° 20%
9 Comfortable



Sun
Dec 24 Showers
60°/44° 60%
4 Moderate



Mon
Dec 25 Scattered Showers
60°/42° 40%
6 Moderate

Don't let Rain Ruin Your Workout

Tue
Dec 26 Sunny
62°/48° 20%
9 Comfortable




Last Updated Dec 17, 10:24 AM CT Printable Forecast


Details Video Text

[Extremeweatherguy]

12z GFS is coming in and seems to be showing a similar "wintry" situation...

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _168.shtml
^^Christmas Eve morning. West gulf low developing and bringing heavy rains and storms to coast and snow/sleet to central and western TX. Temperatures falling below 50F in Houston and well into the low to mid 30s in the Hill Country.^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _180.shtml
^^Christmas Eve evening. Winter weather line slowly shifting eastward with cold rains in east TX and sleet/snow in central and west TX. Temperatures in the 30s and 40s for most places.^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _204.shtml
^^Christmas Evening. Snow, sleet and cold rain falls across the state (wherever precip. is still falling). Temperatures are mainly in the 30s.^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _216.shtml
^^Morning of the 26th. Light snow falls across most of the northern 2/3rds of the state (including Houston). Temperatures in the 20s and 30s for most of the state.^^

http://www.nco.ncep.noaa.gov/pmb/nwprod ... _228.shtml
^^Evening of the 26th. Winter precip. remains (light), but is moving out. Temperatures in the 20s and 30s for most of the state.^^

This is now 3 runs (including the more trusted 0z and 12z) in a row of a winter storm being shown for the Christmas period. I think this can be officially deemed a model trend and BEARS WATCHING for sure.

[Kennethb]

The consistency of the GFS is great to see. Though the GFS generally places ULLs too far south in the long range with a gradual northward placement as the timing narrows. And I would expect the same here. We would need some low dewpoints and the low pressure development in the GOM, in just the right place for wintry precip to occur. Many times when we have wintry precip in the south, it not necessarily extremely cold up north. The longer range models over the past 2 weeks though have been indicating this trough pretty far to the south. And then there is the other issue of moving the ULL to fast. Time and timing will tell the story. Looks live the surface low moves out leaving the ULL behind a tad. Hmm. The overall look of the GFS during this time frame and the days after look suspicious as well. But who knows, maybe we'll get lucky.

[Yankeegirl]

Just get rid of this warm weather... It still stinks... Bah Humbug!

[Johnny]

wxman57 over at KHOU put in his two cents on the deal. Because of the last few model runs, I'm sure Jeff will come out with a christmas update tomorrow.


12Z GFS is more agressive with the cold air and frozen precip than 06Z. The 2meter temps in the 40s probably doesn't reflect evaporative cooling in rain. If the 12Z is correct, then Texas could see a major snow storm on Christmas Eve and the snow may get pretty close to Houston. There, feel better, AD? At the very least, highs in the mid 30s for Houston on Christmas with sleet in the area.

Of course, that's a big IF. We've seen the GFS all over the place in this thread. What will it show tomorrow? We now have the ECMWF to look at. It's in general agreement in the upper low tracking out of the SW U.S. Perhaps a sign that the GFS may be leaning in the right direction? We'll see.

[Extremeweatherguy]

wxman57 over at KHOU put in his two cents on the deal. Because of the last few model runs, I'm sure Jeff will come out with a christmas update tomorrow.


12Z GFS is more agressive with the cold air and frozen precip than 06Z. The 2meter temps in the 40s probably doesn't reflect evaporative cooling in rain. If the 12Z is correct, then Texas could see a major snow storm on Christmas Eve and the snow may get pretty close to Houston. There, feel better, AD? At the very least, highs in the mid 30s for Houston on Christmas with sleet in the area.

Of course, that's a big IF. We've seen the GFS all over the place in this thread. What will it show tomorrow? We now have the ECMWF to look at. It's in general agreement in the upper low tracking out of the SW U.S. Perhaps a sign that the GFS may be leaning in the right direction? We'll see.

This is getting very exciting. Just to hear mets talking about the "chance" of anything frozen on Christmas in SE Texas is very rare.

Hopefully jeff and Air force Met will chime in with their opinions soon.

[jasons2k]

This is interesting, especially since we'll be going up to the DFW area for Christmas.

[wxman22]

One thing to note is the GFS doesnt only show frozen precip around Christmas but it also shows more chances of frozen precip after Christmas and around New Years as more disturbances move aloft. (This seems to be a clissic El nino setup....)


http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_276m.gif




http://www.nco.ncep.noaa.gov/pmb/nwprod ... n_288m.gif

[aggiecutter]

wxman22 might be onto something. The noon Ensembles show that this pattern wants to keep repeating itself into the first of the year. After the first trough pulls out Christmas week, another one replaces it.

The noon Ensembles 12-17-06:
http://wwwt.emc.ncep.noaa.gov/gmb/ens/t ... 21712.html

[HarlequinBoy]

What do the models show for areas east of Texas?

[aggiecutter]

According to the latest Ensembles, this is a classic setup for a major Northern and Central Texas snow-ice event. You have high pressure to the north and northwest and a low in the GOM. If the players line up as the Ensembles suggest, then this has the potential to be a widespread winter storm that the state of Texas hasn't seen in years.

I don't want to get over exuberant, but if I were going to draw up the weather map for a major winter storm in Texas, this would be it. I can't over emphasize that this is the classic setup. Hopefully, it'll come to fruition. We are certainly due one of this magnitude as the last one I can remember on a large scale was January of 2002.

Noon Ensembles Highs and Lows:
http://wwwt.emc.ncep.noaa.gov/gmb/ens/t ... 21712.html

[southerngale]

I'm gonna hold you guys to this pattern change. Who wants to wear a Christmas sweater when it's 80° outside?

As for the winter weather precipitation...I'll certainly do a snow dance, but I won't hold my breath.



Let it snow! Let it snow! Let it snow!

[TrekkerCC]

I'm in a position of being cautiously optimistic for snow near Christmastime. It looks like (if GFS can be believed -- it probably a bit overdone) that we may get a decent snowstorm on Christmas-Eve/Day in North Texas. It ceertainly would be nice, but before I get excited, I want to see the models and actual observations continue to align. However, I will be doing a "snowdance" like SG is doing.

[HarlequinBoy]

I'm surprised Norman already made mention of this in their SWS for the possible icing coming up.

Special Weather Statement

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NORMAN OK
310 PM CST SUN DEC 17 2006

OKZ004>048-050>052-TXZ083>090-181100-
HARPER-WOODS-ALFALFA-GRANT-KAY-ELLIS-WOODWARD-MAJOR-GARFIELD-NOBLE-
ROGER MILLS-DEWEY-CUSTER-BLAINE-KINGFISHER-LOGAN-PAYNE-BECKHAM-
WASHITA-CADDO-CANADIAN-OKLAHOMA-LINCOLN-GRADY-MCCLAIN-CLEVELAND-
POTTAWATOMIE-SEMINOLE-HUGHES-HARMON-GREER-KIOWA-JACKSON-TILLMAN-
COMANCHE-STEPHENS-GARVIN-MURRAY-PONTOTOC-COAL-COTTON-JEFFERSON-
CARTER-JOHNSTON-ATOKA-LOVE-MARSHALL-BRYAN-HARDEMAN-FOARD-WILBARGER-
WICHITA-KNOX-BAYLOR-ARCHER-CLAY-
310 PM CST SUN DEC 17 2006

...WINTER WEATHER POSSIBLE THIS WEEK...

COLD AIR MOVING SOUTH INTO THE AREA WILL COMBINE WITH AN APPROACHING
STORM SYSTEM FROM THE SOUTHERN ROCKIES TO BRING A CHANCE OF FREEZING
RAIN TO PARTS OF WESTERN AND NORTHWESTERN OKLAHOMA LATE MONDAY NIGHT
AND EARLY TUESDAY. THERE IS A CHANCE THAT ICE ACCUMULATIONS WILL BE
SUFFICIENT TO CAUSE TRAVEL PROBLEMS OVER THE NORTHWESTERN THIRD OF
OKLAHOMA BY TUESDAY MORNING. THERE ALSO IS AN OUTSIDE CHANCE OF
SIGNIFICANT ICE ACCUMULATIONS... THAT COULD BE ENOUGH TO DOWN TREES
AND POWER LINES. RESIDENTS IN AND NEAR NORTHWESTERN OKLAHOMA ARE
ADVISED TO KEEP UP TO DATE WITH THE LATEST WEATHER FORECAST
INFORMATION... AND LISTEN FOR POSSIBLE WINTER WEATHER ADVISORIES
THROUGH THE EARLY PART OF THE WEEK.

THE LATEST FORECAST DATA ALSO INDICATE THE POSSIBILITY OF A
SIGNIFICANT WINTER STORM AFFECTING AREAS FROM THE SOUTHERN ROCKIES
INTO TEXAS NEXT WEEKEND. AT THIS TIME... ANY ADVERSE WEATHER FROM
THIS SYSTEM APPEARS MOST LIKELY TO AFFECT AREAS OF THE SOUTHERN
PLAINS WELL TO THE WEST THOUGH SOUTH OF THE OKLAHOMA AND NORTH TEXAS
AREA. HOWEVER THERE ARE MANY UNCERTAINTIES REGARDING THE EVOLUTION
OF THIS SYSTEM... AND THE POTENTIAL EXISTS FOR TRAVEL PROBLEMS OVER
THE PRE-CHRISTMAS WEEKEND IN MANY PARTS OF THE SOUTHWESTERN AND
SOUTH-CENTRAL UNITED STATES. STAY TUNED FOR UPDATES ON THIS
DEVELOPING WEATHER SYSTEM... ESPECIALLY IF YOU HAVE PLANS TO TRAVEL
IN OR THROUGH THESE AREAS OVER THE DAYS IMMEDIATELY PRECEDING
CHRISTMAS.

[Extremeweatherguy]

From the Lake Charles AFD:

LOOKS EVEN MORE FUN IN TIME FOR CHRISTMAS IF THE GFS PLAYS OUT.
THE MODEL DIGS AN EVEN DEEPER TROUGH INTO NRN MEXICO NEXT WEEKEND.
ANOTHER SFC LO IS PROGGED TO FORM OVER THE NWRN GULF ON SUNDAY AND
MOVE EAST ACROSS THE NRN GULF INTO CHRISTMAS EVE. GOOD GULF
MOISTURE PROGGED TO GET WRAPPED AROUND THE LO OVER A COOL AIRMASS
IN PLACE OVER THE AREA...USHERING IN AT LEAST A COLD WET
WEEKEND...IF NOT WORSE. HOWEVER STAYED WITH INHERITED LOW POPS
SINCE WE ARE TALKING 7 DAYS OUT AND A FAIRLY UNCOMMON WEATHER
EVENT FOR THIS PART OF THE WORLD.

From the Houston AFD:

THINGS GET INTERESTING NEXT WEEKEND AS AN UPPER LOW FORMS
TO THE WEST AND A SURFACE LOW FORMS NEAR THE COAST. WILL NEED TO
SEE HOW THE MODEL SOLUTIONS COME TOGETHER OVER THE NEXT FEW DAYS
TO PINPOINT TEMPERATURES AND POPS.

From the Austin AFD:

ANOTHER UPPER LEVEL LOW WILL FOLLOW SUIT ON FRIDAY PROGRESSING OUT
OF CALIFORNIA. HOWEVER...THIS NEXT SYSTEM IS DEEPER AND TAKES A
MORE SOUTHERLY ROUTE THAN THE FIRST UPPER LOW. THE UPPER LEVEL LOW
PRESSURE SYSTEM WILL BE OVER MEXICO BY SATURDAY NIGHT. THIS WILL
BRING CONTINUED CHANCES OF PRECIPITATION TO THE REGION LATE IN THE
WEEK AND INTO NEXT WEEKEND. THIS SYSTEM WILL APPROACH SOUTH
CENTRAL TEXAS JUST IN TIME FOR CHRISTMAS AND IF THE MODELS
CONTINUE WITH THE CURRENT TREND...WINTER-TYPE PRECIPITATION IS POSSIBLE
BY CHRISTMAS EVE.

[gboudx]

From San Angelo

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN ANGELO TX
259 PM CST SUN DEC 17 2006

...

.LONG TERM...
ALL EYES IN THE LONG TERM FOCUSED ON THE SYSTEM NEXT WEEKEND.
ECMWF AND GFS IN REMARKABLE AGREEMENT...WITH ABOUT HALF OR A
LITTLE MORE OF THE GFS ENSEMBLE MEMBERS SHOWING THE SAME.
THUS...A LITTLE MORE CONFIDENCE THAN NORMAL FOR DAY 6 AND 7 IN THE
DEVELOPMENT OF A STRONG UPPER LOW DIVING INTO NORTHERN MEXICO AND
THEN OUT INTO WEST TEXAS. MODELS ALSO IN DECENT AGREEMENT SHOWING
A 1035 MB PLUS SURFACE HIGH DROPPING INTO THE ROCKIES...PUSHING A
COLDER AIR MASS INTO THE REGION AS WELL. AS ALWAYS...SEE A LOT OF
SYSTEMS THAT LOOK REALLY GOOD AT DAY 7 THAT NEVER COME CLOSE TO
PANNING OUT AS MODELS GET MORE INFORMATION. BUT...WITH DECENT
AGREEMENT...WILL ADD A MENTION OF RAIN OR SNOW FOR NEXT
WEEKEND AND LOWER TEMPS JUST A TAD.

[Johnny]

I like what was said out of the Norman, Oklahoma office.


ANY ADVERSE WEATHER FROM
THIS SYSTEM APPEARS MOST LIKELY TO AFFECT AREAS OF THE SOUTHERN
PLAINS WELL TO THE WEST THOUGH SOUTH OF THE OKLAHOMA AND NORTH TEXAS
AREA.