Texas winter weather thread - Cold snap next week

[jasons2k]

Remember (not to bag on the HGX-NWS) in 2004 when ( I think I am correct) they blew the forecast on December 24. My parents saw 8 inches of snow on Christmas. The point is that they have had completely busted forecasts before. Did not the D-FW NWS not even mention snow or ice earlier this week?

that was a hundred year storm. I wouldn't fault anyone on that. not one TX office was able to nail that one.

However this is one thing JB nailed. I know, I know...he overhypes 90% of the time but I was a subscriber back then and he forecasted a significant snow event for S/SE TX several days beforehand and (maybe arrogantly?) declared the WFOs would badly bust.

[wall_cloud]

As for why it's from LCH, in the past it has been usually due to a software problem where they can't issue; an adjacent office needs to for them.

I think sometimes the software they use to write discussions have techincal difficulties and they ask adjacent Lake Charles NWS to assist them in the discussion. If I'm not mistaken it has also happened to Austin/San Antonio NWS and Forth Worth NWS had to fill in.

every office has the same software and while this can happen, I think its pretty rare to have to go to back-up. In 4 years I have never had to have another office back us up (except with scheduled upgrades)

[TexasStooge]

From what I've heard on NOAA Weather Radio, the rest of the Winter Storm Watch may be upgraded to a warning later tonight.

[wall_cloud]

However this is one thing JB nailed. I know, I know...he overhypes 90% of the time but I was a subscriber back then and he forecasted a significant snow event for S/SE TX several days beforehand and (maybe arrogantly?) declared the WFOs would badly bust.

even a blind squirril find a nut occasionally I don't consider that to be a big deal when you are wrong as much as you are right.

[CaptinCrunch]

Decatur has now dropped to 61, and Gainesville 63

[wall_cloud]

Wall Cloud,

Could it be that the mixed bag of moisture will completely fool many NWS stations? Could this be a significant icing event even as far south as College Station? The reason why I ask is that the ice/sleet/snow lines seem to making its way south as time wears on. I know that WXman and others have commented on how models do not handle cold weather well. I am no expert and I have nary a clue as to the why's and whatnot. Any amateur meterologists can answer too. Thanks

well, too many people rely on MOS for one thing and MOS is not set up to handle unusual events very well. It uses a climatology database to produce the numbers so if the event is a rare one, it won't be in the database and it will give you something a lot less extreme.

As for the model biases...there are many. But one problem is the resolution of the modles and the observation network. A lot of things can slip through the cracks, between obs and model levels. i hope this makes sense.

[gboudx]

Decatur has now dropped to 61, and Gainesville 63

Yep, Weatherbug just updated. Wow. Time to set the location further East.

[JenBayles]

Our Houston winters have been very much on the warm side the past few years. I can't even remember the last time I experienced a 30 degree drop in one hour.

BTW, I have a weather backside instead of a weather elbow (surgery related arthritis) and it's screaming at me today. I'll buy into my b**t forecast over many that I'm hearing today.

[jasons2k]

I have the front in blue on this image; the wind shift is showing-up nicely on GR3 now:

[jasons2k]

Front passing Mineral Wells right now; that 81 should drop any minute...

[Dallasis2hot]

Snow accumulations have just been lowered for all the DFW zones. Prior to this 4pm update, it read 1-3" possible. Now reads less than 1 inch. Northern zones lowered as well.

[CaptinCrunch]

Decatur now at 50 degrees

[gboudx]

Snow accumulations have just been lowered for all the DFW zones. Prior to this 4pm update, it read 1-3" possible. Now reads less than 1 inch. Northern zones lowered as well.

Where did you see or hear that?

[Dallasis2hot]

Snow accumulations have just been lowered for all the DFW zones. Prior to this 4pm update, it read 1-3" possible. Now reads less than 1 inch. Northern zones lowered as well.

Where did you see or hear that?

NWS.NOAA.GOV

[CaptinCrunch]

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FORT WORTH TX
357 PM CST WED NOV 29 2006

.DISCUSSION...
ARCTIC COLD FRONT ALREADY MOVING THROUGH THE NW CWA WITH A 35
DEGREE DROP NOTED IN THE FIRST HOUR. A BROKEN LINE OF STORMS HAVE
DEVELOPED OVER THE NORTHWEST CWA AHEAD OF THE FRONT WITH STORMS
ALSO DEVELOPING ALONG THETA E AXIS ACROSS THE I-35 CORRIDOR OVER
THE SOUTHERN ZONES. POWERFUL UPPER LEVEL LOW IS NOW CLOSING OFF
OVER NEW MEXICO AND WILL BE PROVIDING THE INTENSE DYNAMIC FORCING
FOR ISOLATED SEVERE STORMS OVER NORTH TEXAS. SPECIAL 18Z FWD
SOUNDING...INDICATES DECENT INSTABILITY...WITH STRONG 0-6 KM SPEED
SHEAR...LOW LCLS AND 0-3 KM HELICITY VALUES SUPPORTIVE OF
SUPERCELL STRUCTURES WITH LOW LEVEL MESOCYCLONES. THE PRIMARY
THREAT FROM THESE STORMS IS GOING TO BE LARGE HAIL..BUT UNTIL THE
FRONT UNDERCUTS THE STORMS...WIND DAMAGE AND ISOLATED TORNADOES
WILL BE POSSIBLE. LARGE HAIL THREAT WILL CONTINUE INTO THE
OVERNIGHT HOURS AS ELEVATED INSTABILITY WILL REMAIN SUFFICIENT
FOR SUCH. COOLING ALOFT AND AT THE SURFACE MAY ALLOW FOR AN
EARLIER OCCURRANCE OF BRIEFLY ACCUMULATING SLEET/SMALL HAIL IN
THUNDERSTORM CORES...SO THIS MAY NEED TO BE MONITORED.

FRONT IS AHEAD OF SCHEDULE...AND WILL BE MOVING THROUGH MUCH OF
THE CWA THIS EVENING. STRONG COLD ADVECTION AND ASSISTANCE FROM
EVAPORATIVE COOLING...SHOULD ALLOW TEMPERATURES TO FALL BELOW 32
OVER THE NW COUNTIES BY MIDNIGHT. BY 6 AM FREEZING TEMPS SHOULD
BE REACHING THE METROPLEX AND MUCH OF THE WESTERN CWA. TEMPS
WILL CONTINUE TO GRADUALLY FALL INTO THE 20S AND LOWER 30S
AREAWIDE DURING THE DAY THURSDAY.

EVEN THOUGH THE FRONT IS AHEAD OF SCHEDULE...MODELS ARE A LITTLE
SLOWER WITH THE AFOREMENTIONED UPPER LEVEL LOW. AS THE LOW MOVES
INTO TEXAS OVERNIGHT AND EARLY TOMORROW MORNING...IT WILL PROVIDE
NUMEROUS UPWARD FORCING MECHANISMS. CONFIDENCE IN A SIGNIFICANT
WINTER WEATHER EVENT HAS INCREASED ENOUGH FOR THE ISSUANCE OF A
WINTER STORM WARNING ALONG AND NORTH OF A LINE FROM COMANCHE TO
ARLINGTON TO COOPER.

STRONG ISENTROPIC LIFT OVER THE SHALLOW ARCTIC FRONT WITH ELEVATED
INSTABILITY ALOFT WILL ALLOW FOR WIDESPREAD CONVECTION WITH
LOCALLY HEAVY RAIN AND SMALL HAIL/SLEET THROUGH THE OVERNIGHT
HOURS. FRONTOGENESIS PROGS INDICATE LIFTING AND BANDED
PRECIPITATION OCCURRING AFTER MIDNIGHT AND INTO TOMORROW MORNING.
AS THE LOW APPROACHES DYNAMIC FORCING WILL BECOME MAXIMIZED...AND
INTENSE COOLING/LIFTING WILL FORCE THE ATMOSPHERIC COLUMN NEAR OR
BELOW FREEZING FOR THE WARNING AREA. THEREFORE...A TRANSITION TO
SLEET AND SNOW IS EXPECTED BY MID MORNING FROM WEST TO EAST.

LIQUID QPF OUTPUT FROM THE MODELS IS FORECAST TO REACH A HALF INCH
ACROSS THE NW CWA AFTER MIDNIGHT. THIS AMOUNT OF RAINFALL MAY BE
ENOUGH TO KEEP TEMPERATURES ABOVE FREEZING...BUT IF NOT...THERE
WILL BE SERIOUS CONCERNS WITH ICING ON ELEVATED SURFACES AND TREE
LIMBS. THIS WILL BEAR CLOSE MONITORING DURING THE NEXT 18 HOURS.
FREEZING RAIN IS EXPECTED TO MOVE SOUTH INTO THE METROPLEX AND BE
ENCOMPASSING MUCH OF THE WINTER STORM WARNING AREA AFTER DAYBREAK.

GIVEN THE TRACK OF THE 850 MB LOW...WE EXPECT HIGHEST SNOWFALL
AMOUNTS OF 1-3 INCHES ACROSS THE EXTREME NW CWA. IN ADDITION...THIS
AREA WILL SOME ICE/SLEET ACCUMULATIONS TONIGHT BEFORE IT SNOWS.
ACROSS SOUTHERN HALF OF THE WINTER STORM WARNING AREA (INCLUDING
THE METROPLEX)...WE EXPECT UP TO 1/4 OF AN INCH OF ICE/SLEET WITH
AN INCH OF SNOW BEFORE EVERYTHING ENDS IN THE AFTERNOON. ADDITIONAL
LIGHT WRAP-AROUND SNOW WILL BE POSSIBLE ALONG THE RED RIVER IN
THE AFTERNOON...BUT THINGS SHOULD BE SETTLING DOWN BY THEN.

TO THE SOUTH OF THE WINTER STORM WARNING AREA...RAIN WILL CHANGE
OVER TO FREEZING RAIN AND LIGHT SLEET DURING THE MORNING HOURS AND
A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR MUCH OF THE SOUTHERN
CWA. ACCUMULATIONS ARE EXPECTED TO BE BELOW 1/10 OF AN INCH IN THE
ADVISORY AREA...BUT IT IS ENOUGH TO CREATE PROBLEMS ON BRIDGES
AND OVERPASSES.

WE WILL NOT ISSUE A FREEZE WARNING NOW...BECAUSE WSW TAKES
PRECEDENCE OVER IT...BUT A HARD FREEZE IS EXPECTED THURSDAY NIGHT
AS SKIES CLEAR OUT AND WINDS GO CALM. IN ANTICIPATION OF SNOW/ICE
ON THE GROUND...HAVE LOWERED TEMPS ACROSS THE NORTHERN CWA INTO
THE UPPER TEENS IN SOME SPOTS.

REMAINDER OF FORECAST IS EASY. WITH CHILLY WEATHER CONTINUING AS
REINFORCING POLAR HIGHS MOVE INTO THE AREA. MOISTURE LOOKS LIMITED
SO NO POPS IN THE FORECAST BEYOND TOMORROW EVENING.

FREASH OFF THE WIRE!!

[gboudx]

Mineral Wells from 81 to 57.

[JenBayles]

Dallas AFD:
(Edit - looks like Capn' beat me to the Submit button, so have erased for sake of brevity...) Jen

[jasons2k]

Wow Cooke County 12NW Gainseville 1.75" hail and 60 mph wind gusts with the storm earlier.

Gainesville now down to 52, Mineral Wells came down to 57

Front is on Denton's Doorstep

[wall_cloud]

1.73"?

[jasons2k]

An updated image with the front in blue - you might have to click it 2 or 3 times for full resolution: