Winter Storm and Winter Weather in Texas, December 25, 2012

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LUBBOCK TX
1017 PM CST MON DEC 24 2012

.UPDATE...
THE AFD YOU HAVE WAITED FOR IS READY BEFORE THE STORM
ALTHOUGH THE FORM IS WEIRD AND LANGUAGE NOT THE NORM.
THE STORM THAT IS ARRIVING IS BECOMING MORE CLEAR...
A FEW SCENARIOS ARE POSSIBLE WITH THE EVENT DRAWING NEAR.

WATER VAPOR SATELLITE SHOWS THE STORM STILL COMING OUR WAY...
SOUTHEAST OF THE FOUR CORNERS IT SPINS TO ARRIVE CHRISTMAS DAY.
THE RAP AND NAM ARE BREAKING OUT SNOW ACROSS THE NORTHWEST
AS EARLY AS 08 TO 10Z WHICH IS WHAT THEY HAVE GUESSED.

285K ISENTROPIC LIFT AND MOISTURE INCREASE BY LATE MORNING...
THE RAP AND NAM SHOW SNOW AMOUNTS THAT MAY WARRANT A WARNING.
MOST FAVORED AREA ARE ACROSS NORTHERN COUNTIES INTO THE PLAINS...
SNOW BANDING IS HINTED AS THE MODELS LOOSE THE REINS.

TEMPERATURE PROFILES ARE STILL EXPECTED TO FALL BELOW FREEZING
WHICH CONCERNS OF A MIX OF RAIN AND SNOW STILL ARE EASING.
THE DEPTH OF COLD AIR INCREASES RAPIDLY AFTER SUNRISE...
STRONG NORTH WINDS COMBINED WITH SNOW COULD BE BLINDING WE ADVISE.

THE BANDS EASE EARLY MORNING AND MORE SNOW LOOKS TO FORM...
ISENTROPIC LIFT KICKS IN NEAR CHILDRESS AND EAST OF THE STORM.
THE AMOUNTS BECOME TRICKY AND THERE IS QUITE A RANGE AS THE LIFT
STARTS TO WEAKEN AND MOISTURE LEVELS START TO CHANGE.

WITH SNOW STARTING OUT WEST AND RAPIDLY MOVING TO THE EAST...
THE LOCATION/RATE OF THE SNOW WILL BE IMPORTANT TO SAY THE LEAST.
IF THE MOST OPTIMISTIC MODELS TURN OUT TO BE CORRECT...
SOME LOCATIONS MAY SEE 4 TO 6 INCHES WHICH WE CANNOT NEGLECT.

WILL HOLD OFF WITH UPGRADING THE ADVISORY TO A WARNING
BUT IT MAY BE REQUIRED WHICH MAY HAPPEN EARLY TUESDAY MORNING.
AS IT STANDS RIGHT NOW THE HUB CITY MAY TURN WHITE
WITH ONE OF THE BANDS APPROACHING CHANCES ARE BETTER THAN SLIGHT.

TRAVEL REMAINS HIGHLY DISCOURAGED IF YOU WANT TO GO NORTH...
ONCE THE SNOW STARTS TO FALL AND THE WIND BLOWS THENCEFORTH.
WE WILL HOLD OUR BREATHS AS WE FINALLY HEAD OUT THE DOOR...
AND ANOTHER SHIFT WILL ARRIVE OUT HERE ON THE OPERATIONS FLOOR.

THE POTENTIAL IS THERE FOR THIS STORM TO CHANGE IT/S MIND...
IF THINGS DRASTICALLY CHANGE THEN THE FORECAST IS IN A BIND.
HOWEVER OUR CONFIDENCE IS INCREASING THAT THE SNOW WILL SOON FALL
WATCHING...OBSERVING...AND FORECAST IN CASE OF A CURVE BALL.

STAY TUNED TO YOUR FAVORITE SOURCES OF WEATHER INFORMATION...
THE SITUATION IS FLUID...CHANGING...AND ALWAYS IN TRANSLATION.
THIS FORECAST SHIFT WILL LEAVE IN A BIT LESS THAN TWO HOURS
HOPING TO WAKE UP TO SEE VERIFICATION IN THE FORM OF SNOW SHOWERS.

FROM THIS FORECASTER TO YOU WHO TRUST US FOR YOUR FORECAST...
I HOPE THIS AFD HELPS YOU AND INFORMS YOU...WITHOUT BEING AGHAST.
MY PURPOSE IS SOLELY TO SHOW YOU WE CARE
AND TO BE METEOROLGICALLY SOUND AND DO IT WITH FLAIR.

TOMORROW SOON WILL ARRIVE AND IT COULD POSSIBLY BE WHITE
SO MERRY CHRISTMAS TO YALL AND TO ALL A GOOD NIGHT!

JORDAN/WFO LUBBOCK

&&

.PREV DISCUSSION... /ISSUED 543 PM CST MON DEC 24 2012/

AVIATION...
CURRENT VFR CONDITIONS WILL GRADUALLY DECREASE INTO MVFR RANGE
TOMORROW MORNING AS A STRONG COLD FRONT PUSHES INTO THE REGION. AT
THE SAME TIME...A STORM SYSTEM WILL MOVE OVER THE REGION RESULTING
IN WINTER PRECIPITATION.

FOR KCDS...MAIN IMPACT WILL BE LOW VISIBILITIES IN BLOWING SNOW
THAT WILL LAST MUCH OF THE MORNING THROUGH AFTERNOON HOURS.
VISIBILITIES WILL DROP INTO MVFR TO IFR RANGE WITH CEILINGS IN THE
MVFR RANGE. FRONT WILL ARRIVE BEFORE SUNRISE/11Z AND INCREASE WIND
SPEEDS FROM THE NORTH AT 25 TO 35 KNOTS AND GUSTS APPROACHING 40
KNOTS. STORM SYSTEM WILL HAVE PUSHED EAST BY MID-DAY BUT
PRECIPITATION WILL SLOWLY END AFTER IT PASSES. CONDITIONS WILL
RETURN BACK TO MVFR TO VFR RANGE AROUND SUNSET.

FOR KLBB...HEAVIEST SNOW IS EXPECTED TO REMAIN NORTH OF THE
REGION HOWEVER BRIEF PERIODS OF SNOW WILL BE POSSIBLE. CONFIDENCE
IS LOW AT THIS TIME AND WILL NOT INCLUDE IN THE TAF AT THIS TIME.
STRONG COLD FRONT WILL ARRIVE AROUND 11Z AND INCREASE THE WIND
SPEED ALSO TO THE 20 TO 30 KNOT RANGE WITH GUSTS APPROACHING 40
KNOTS. DRY CONDITIONS AND STRONG WINDS WILL RESULT IN PERIODS OF
BLOWING DUST THAT WILL REDUCE VISIBILITY SOMEWHAT...HOWEVER IT
SHOULD REMAIN IN THE VFR RANGE. CONDITIONS WILL IMPROVE LATE IN
THE DAY AS WIND SPEEDS DECREASE.

JORDAN

PREV DISCUSSION... /ISSUED 310 PM CST MON DEC 24 2012/

SHORT TERM...
HIGH IMPACT WINTER STORM WILL DEVELOP ACROSS THE PANHANDLE OVERNIGHT
AND MOVE EAST-SOUTHEAST INTO OK ON CHRISTMAS DAY. 12Z AND 18Z MODEL
RUNS CONTINUE FAIRLY GOOD CONTINUITY WITH THE MID-LEVEL TROUGH
DIGGING ACROSS UT THIS AFTERNOON CLOSING OFF AND DEEPENING NORTH OF
LUB BY 12Z TUE. THE SYSTEM THEN EJECTS ALONG OR SOUTH OF THE RED
RIVER CHRISTMAS DAY. THE FAST MOVEMENT OF THE SYSTEM SHOULD LIMIT
THE OVERALL AFFECTS OF ACCUMULATING PRECIP YET THERE IS STILL ENOUGH
LIFT AND INITIAL MOISTURE TRANSPORT INTO THE DEEPENING SYSTEM TO
CAUSE SOME CONCERN.

EXPECT PRECIP TO BREAK OUT NEAR THE NM STATE LINE AFTER MIDNIGHT AS
JET ENERGY DIVES TOWARD THE BASE OF THE TROUGH. THE PRECIP SHIELD
SHOULD BROADEN AND MOVE EAST ACROSS THE NORTHERN SOUTH PLAINS AND
PANHANDLE THROUGH THE MORNING TUE. THE TRACK OF THE UPPER LOW WOULD
PLACE THE FAVORED LOCATION FOR THE HEAVIEST PRECIP NORTH OF A LINE
FROM HEREFORD TO CHILDRESS BUT WITH THE TENDENCY FOR A FEW MODELS TO
CONTINUE TO DIG THE SYSTEM FURTHER SOUTH HAVE BROADENED THE AREA OF
ON INCH OR GREATER SNOW TO INCLUDE THE FAR NORTHERN SOUTH PLAINS.

WHILE THE WESTERN PORTION OF THE WINTER WEATHER ADVISORY AREA MAY
SEE LIMITED SNOW TOTALS...STRONG NORTH WINDS IN THE WAKE OF THE
CANADIAN FRONT WILL CREATE AREAS OF BLOWING SNOW WITH NEAR WHITE-OUT
CONDITIONS EXPECTED FOR THE MAJOR ROADS HEADING INTO THE PANHANDLE.
THE NAM IS FORECASTING 3HR PRESSURE RISES NEAR 10MB ACROSS EASTERN
NM BY 12 TUE SO WIND SPEEDS ARE EXPECTED TO BE ON THE UPPER END OF
THE RANGE PERHAPS PUSHING ADVISORY LEVEL AT TIMES IN THE EARLY
AFTERNOON. THE TRANSITION OF PRECIPITATION FROM RAIN TO SNOW SHOULD
BE VERY QUICK GIVEN THE STRONG DYNAMICAL COOLING AND WET-BULBING
FROM A RELATIVE DRY LOW LEVEL AIRMASS. STILL SIGNIFICANT WARM
ADVECTION IN THE LOW LEVELS WILL BE ONGOING AHEAD OF THE SYSTEM AND
THERE WILL BE A WARM NOSE TO OVERCOME. WOULD NOT BE SURPRISED TO SEE
SOME SLEET OR RAIN SHOWERS AHEAD OF THE MAIN PRECIP IN THE ROLLING
PLAINS VERY EARLY IN THE DAY. AS A RESULT HAVE LEFT A BRIEF WINDOW
OF RA/SN OR PL/SN AHEAD OF THE UPPER LOW AS IT TRACKS EAST BETWEEN
12Z AND 15Z TUE. PRECIP WILL TRANSITION TO ALL SNOW THEN COME TO AN
END RATHER QUICKLY TUE AFTERNOON FROM I-27 EASTWARD BUT ANY
REMAINING MESOSCALE SNOW BANDS ON BACK SIDE OF SYSTEM WILL CONTINUE
TO CREATE AREAS OF VERY LOW VISIBILITY. WE HAVE EXTENDED THE WINTER
WEATHER ADVISORY THROUGH 00Z TO ACCOUNT FOR ANY SLOWER MOVEMENT.

A VERY LOW DIURNAL TEMPERATURE RANGE IS EXPECTED CHRISTMAS DAY WITH
SOME LOCATIONS POSSIBLY REMAINING IN THE TEENS FAR NORTHWEST WITH
STEADY OR DROPPING TEMPERATURES ELSEWHERE. WIND CHILL VALUES COULD
BE NEAR OR SLIGHTLY BELOW ZERO IN A FEW LOCATIONS EARLY IN THE
MORNING.

LONG TERM...
UPPER LOW PRODUCING A WIDE RANGE OF INCLEMENT WEATHER ACROSS THE
SOUTHERN CONUS ON CHRISTMAS DAY PROGGED TO BE ALL THE WAY TO THE
ARKLATEX BY 26/00Z. THIS WILL RESULT IN RAPIDLY IMPROVING CONDITIONS
ACROSS THE FORECAST AREA THROUGH THE EARLY CHRISTMAS EVENING HOURS.
ANY LINGERING SNOWFALL OVER THE SOUTHEAST PANHANDLE OR NORTHERN
ROLLING PLAINS WILL END WHILE CLOUDS AND WINDS WILL ALSO BE ON THE
DECREASE AS A SURFACE PRESSURE RIDGE SETTLES SOUTH ACROSS WEST
TEXAS. THIS WILL LEAD TO A VERY COLD NIGHT ACROSS THE REGION WITH
WEDNESDAY MORNING LOWS FALLING INTO THE 5 TO 15 DEGREE RANGE ACROSS
ALL OF THE FORECAST AREA PER MOS GUIDANCE.

GFS/ECMWF DETERMINISTIC RUNS INDICATE A CONTINUATION OF THE
PROGRESSIVE PATTERN THROUGH THE 7 DAY PERIOD. HIGHLIGHTS WILL BE
ANOTHER UPPER LOW TRANSLATING ACROSS THE MIDWEST BY THE END OF THE
WEEK AND ANOTHER RATHER POTENT LOOKING CLOSED LOW SOMEWHERE ACROSS
THE SW CONUS BY EARLY NEXT WEEK. THE MID WEEK SYSTEM WILL PASS
MAINLY NORTH OF THE FORECAST AREA AND PROBABLY ONLY RESULT IN A
TIGHTENING OF LOWER HEIGHT GRADIENTS TO RESULT IN BREEZY CONDITIONS
ACROSS THE EXTREME SOUTHERN PANHANDLE ON THURSDAY. TEMPERATURES WILL
MODERATE SOME BY THURSDAY WITH SURFACE WINDS BACK AROUND TO THE
SOUTH AND WEST BUT ANOTHER COLD FRONT SHOULD KNOCK OFF AROUND 10
DEGREES OR SO FOR FRIDAY. SHORT WAVE RIDGING WILL THEN ENSUE FOR THE
UPCOMING WEEKEND WITH TEMPERATURES WARMING ONCE AGAIN. SHOULD REMAIN
DRY THROUGH THE LONG TERM PERIOD.

THE LATTER UPPER LOW SHOWN BY BOTH GFS/ECMWF WOULD BE INTERESTING
SHOULD ANY SEMBLANCE OF IT ACTUALLY PAN OUT. BOTH MODELS CLOSE OFF A
LOW AND ADVECT IT TOWARD WEST TEXAS AROUND OR SHORTLY AFTER NEW
YEARS DAY AND BOTH LOOK VERY WET FOR A LARGE PART OF THE SOUTHWEST
US. OF COURSE...WE WILL ONLY BE MONITORING THE MODEL SOLUTIONS FOR
NOW TO SEE IF THIS TREND CONTINUES AND WHAT...IF ANY...IMPACTS THIS
LOW MAY EVENTUALLY HOLD FOR THE FORECAST AREA. JW

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        17  20   7  39  18 /  70  80  10   0   0
TULIA         20  22   8  36  16 /  60  80  10   0   0
PLAINVIEW     21  24   8  38  18 /  50  80  10   0   0
LEVELLAND     27  29  13  39  18 /  40  20   0   0   0
LUBBOCK       24  28  10  39  19 /  30  30  10   0   0
DENVER CITY   35  35  15  41  19 /  10  10   0   0   0
BROWNFIELD    30  32  13  40  19 /  10  10   0   0   0
CHILDRESS     28  28  10  28  16 /  30  80  10   0   0
SPUR          27  29  12  37  19 /  10  30  10   0   0
ASPERMONT     30  30  13  35  19 /  10  40  10   0   0

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 6 PM CST TUESDAY FOR THE FOLLOWING
ZONES: TXZ021>032.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LUBBOCK TX
225 PM CST MON DEC 24 2012

TXZ021>044-252030-
PARMER-CASTRO-SWISHER-BRISCOE-HALL-CHILDRESS-BAILEY-LAMB-HALE-
FLOYD-MOTLEY-COTTLE-COCHRAN-HOCKLEY-LUBBOCK-CROSBY-DICKENS-KING-
YOAKUM-TERRY-LYNN-GARZA-KENT-STONEWALL-
225 PM CST MON DEC 24 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE EXTREME SOUTHERN TEXAS
PANHANDLE...SOUTH PLAINS AND ROLLING PLAINS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

AREAS OF SNOW WILL DEVELOP ACROSS THE PANHANDLE LATE TONIGHT.
LIGHT ACCUMULATIONS OF SNOW MAY BEGIN BEFORE SUNRISE CHRISTMAS DAY
CREATING HAZARDOUS DRIVING CONDITIONS.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY

SNOW AND BLOWING SNOW WILL IMPACT THE TEXAS PANHANDLE...NORTHERN
SOUTH PLAINS AND ROLLING PLAINS CHRISTMAS DAY. THE COMBINATION OF
LIGHT TO MODERATE SNOW AND NORTH WINDS 20 TO 25 MPH WILL CREATE
PERIODS OF WHITE-OUT CONDITIONS AND VERY DANGEROUS TRAVEL THROUGH
THE DAY. SNOW ACCUMULATIONS UP TO 2 INCHES WILL BE POSSIBLE WITH
BLOWING AND DRIFTING SNOW IMPACTING AREA ROADWAYS. IN ADDITION TO
THE SNOW...VERY COLD TEMPERATURES WITH WIND CHILL VALUES NEAR ZERO
WILL BE POSSIBLE CHRISTMAS MORNING AND AGAIN WEDNESDAY MORNING
ACROSS MUCH OF THE SOUTH PLAINS AND SOUTHERN PANHANDLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTERS AND LAW ENFORCEMENT OFFICIALS ARE ENCOURAGED TO REPORT
SNOWFALL AMOUNTS TO THE NATIONAL WEATHER SERVICE IN LUBBOCK LATE
TONIGHT AND CHRISTMAS DAY.