000
FXUS64 KLUB 022346
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
546 PM CST MON DEC 2 2013

.AVIATION...
NO AVIATION ISSUES ARE EXPECTED FOR THE NEXT 24 HOURS. WINDS WILL
GENERALLY BE OUT OF THE WEST AND WILL BECOME BREEZY TUES
AFTERNOON. HIGH CLOUDS WILL BE ON THE INCREASE FROM THE WEST.

&&

.PREV DISCUSSION... /ISSUED 356 PM CST MON DEC 2 2013/

SHORT TERM...
DRY AND MILD CONDITIONS HOLDING THROUGH TUESDAY WITH MINOR CHANGES
TO THE PREVIOUS FORECAST. UPPER LEVEL FLOW FROM THE WEST-NORTHWEST
THIS AFTERNOON WILL GRADUALLY BACK TO WEST-SOUTHWESTERLY BY LATE
TUESDAY AS A TROUGH IN THE UPPER ATMOSPHERE TWIRLS SOUTHEASTWARD
THROUGH THE INTER-MOUNTAIN WEST...THOUGH EXPECTED TO WEAKEN. SURFACE
LOW PRESSURE TROUGH FROM THE CENTRAL PANHANDLE THROUGH THE ROLLING
PLAINS IS EXPECTED TO MAINTAIN WITH GENERALLY WESTERLY LOW LEVEL
DOWNSLOPE BREEZES THROUGH THE NIGHT AND ON TUESDAY. MIXING TUESDAY
AFTERNOON EXPECTED NOT MUCH ABOVE 800 TO 750 MB DEPTH...MAY BE JUST
DEEP ENOUGH TO TAP SOMEWHAT STRONGER FLOW AT THAT LEVEL. THIS SHOULD
LEAD TO LOW-END WINDY CONDITIONS FAVORING OUR NORTHERN ZONES...WITH
BREEZY WINDS ELSEWHERE. HIGH CLOUDS LIKELY TO GRADUALLY INCREASE BY
LATE ON TUESDAY AS WELL. TEMPERATURES SHOULD BE ABLE TO CLIMB NICELY
IN THE DRY-ADIABATIC DOWNSLOPE ENVIRONMENT TO AS MUCH AS 20 DEGREES
ABOVE NORMAL TUESDAY AFTERNOON. ENJOY...GET THOSE HOLIDAY LIGHTS UP.
THE MILD AIR IS IN ITS WANING HOURS.  RMCQUEEN

LONG TERM...
PLENTY TO CONSIDER THIS GO AROUND AS THE WEATHER PENDULUM IS SET TO
SWING BACK FROM SPRINGLIKE TO WINTER FOR THE SECOND HALF OF THE
WEEK. TEMPERATURES BY THE LATTER HALF OF THE WEEK ON INTO THE
WEEKEND WILL STRUGGLE TO BREAK THE FREEZING MARK AND MANY SPOTS MAY
NOT MAKE IT OUT OF THE 20S FROM THURSDAY THROUGH SATURDAY. IN
ADDITION...IT IS APPEARING MORE LIKELY THAT WINTRY PRECIPITATION
WILL MAKE ANOTHER VISIT TO WEST TEXAS ANYTIME FROM LATE WEDNESDAY
NIGHT ON THROUGH EARLY FRIDAY...PERHAPS IN TWO EPISODES.

THE BIG CHANGES ARE COURTESY OF A LARGE TROUGH THAT IS JUST
BEGINNING TO DIG INTO THE NORTHWESTERN CONUS. THIS TROUGH WILL TAKE
UP RESIDENCE ACROSS THE WESTERN STATES BY MID-WEEK WHERE IT WILL
LIKELY REMAIN IN SOME FORM OR ANOTHER THROUGH THE WEEKEND AND
PERHAPS INTO EARLY NEXT WEEK. THIS PATTERN WILL RESULT IN NEAR
MERIDIONAL FLOW ALOFT ALONG THE WESTERN EDGE OF THE CONTINENT WHICH
IN TURN WILL PROMOTE A DUMP OF VERY COLD AIR OUT OF WESTERN CANADA
AND ALASKA SOUTHWARD THROUGH WEST TEXAS BY MID-WEEK.

INITIAL CHALLENGES REVOLVE AROUND THE TIMING/POSITION OF THE FRONT
ON WEDNESDAY. MOST NWP SHOWS THE FRONT BACK-DOORING INTO THE SOUTH
PLAINS REGION EARLY WEDNESDAY...THEN STALLING OUT /PERHAPS EVEN
RETREATING NORTHEASTWARD/ DURING THE DAY UNDER STRONG SOUTHWEST FLOW
ALOFT BEFORE SURGING THROUGH THE REMAINDER OF THE FA WEDNESDAY
EVENING/NIGHT. THERE IS ALWAYS CONCERN THAT THE FRONT MAY NOT STOP
IF IT IS DENSE ENOUGH AND THIS COULD WELL HAPPEN IF MODELS ARE UNDER
FORECASTING THE STRENGTH OF THE INITIAL SURGE OF COLD AIR...BUT FOR
NOW WE HAVE SIDED WITH THE NWP. THUS...WE HAVE THE FRONT DEPICTED
ROUGHLY ALONG THE EDGE OF THE CAPROCK BY MID/LATE AFTERNOON
WEDNESDAY...WITH A LARGE TEMPERATURE GRADIENT ACROSS THE
CWA...RANGING FROM HIGHS IN THE 40S NEAR CHILDRESS TO LOWER 70S AT
DENVER CITY. IN THE MIDDLE IT COULD BE PARTICULARLY TRICKY...WITH
FORECAST HIGHS AT LUBBOCK RANGING ANYWHERE FROM THE 30S TO HIGH
60S. TIME WILL TELL.

REGARDLESS...THE CANADIAN AIR WILL ADVANCE ACROSS THE SOUTH PLAINS
WEDNESDAY NIGHT. AT THIS SAME TIME...ISENTROPIC UPGLIDE WILL QUICKLY
INCREASE ABOVE THE COLD DOME...WITH A BRIEF BOUT OF FRONTOGENETICAL
FORCING AND A SLUG OF SUB-TROPICAL MOISTURE RACING OVER FROM THE
PACIFIC. THE COMBINATION OF FACTORS SHOULD RESULT IN A QUICK
INCREASE IN PRECIPITATION CHANCES LATE WEDNESDAY NIGHT...WITH
CURRENT INDICATIONS THAT PRECIPITATION WILL BLOSSOM AFTER 06Z AS THE
AIR COLUMN SATURATES FROM THE TOP DOWN. THE DEPTH AND STRENGTH OF
THE COLD AIR THEN BECOMES THE NEXT QUESTION MARK...AS IT WILL
DICTATE THE P-TYPE. TENDED TO FAVOR THE NAM WHICH OFTEN HANDLES THE
SHALLOW COLD AIR BETTER THEN OTHER MEDIUM RANGE MODELS. GIVEN
THIS...IT APPEARS ENOUGH COLD AIR WILL MOVE INTO ALL BUT THE FAR
SOUTHWESTERN ZONES TO BRING WINTRY MIX...ANYTHING FROM FREEZING
RAIN...TO SLEET AND EVEN SNOW /AT LEAST ACROSS THE NORTHWEST ZONES/.
IF THE GFS IS CORRECT /WHICH WE ARE LEANING AGAINST AT THIS
POINT/ MUCH OF THE AREA WOULD REMAIN WARM ENOUGH FOR ONLY A CHILLY
RAIN THROUGH EARLY THURSDAY.

IT DOES APPEAR FORCING MAY WANE AND SHIFT EAST THURSDAY
AFTERNOON...BUT MORE LARGE SCALE ASCENT ASSOCIATED WITH AN EMBEDDED
UPPER LEVEL DISTURBANCE ...SHOULD RENEW/REINVIGORATE PRECIPITATION
CHANCES THURSDAY EVENING INTO EARLY FRIDAY. BY THIS TIME...THE COLD
AIR WILL HAVE DEEPENED...AND SNOW SHOULD BECOME THE DOMINATE P-TYPE
ACROSS THE SOUTHERN PANHANDLE AND NORTHERN SOUTH PLAINS...WITH A MIX
OF SLEET AND SNOW /WITH EVEN FREEZING RAIN ACROSS THE SOUTH/
TRANSITIONING TO ALL SNOW BY EARLY FRIDAY...WHEN PRECIPITATION
CHANCES SHOULD QUICKLY WANE. IT DOES APPEAR MODEST ACCUMULATIONS OF
SOME COMBINATION OF ICE...SLEET AND SNOW WILL BE POSSIBLE OVER
MUCH/ALL OF THE CWA BETWEEN LATE WEDNESDAY NIGHT AND EARLY FRIDAY
MORNING. IN ADDITION...THE COLD AIR COUPLED WITH NORTHEAST TO
EASTERLY BREEZES WILL LIKE PUSH WIND CHILLS INTO THE SINGE DIGITS
BOTH THURSDAY AND FRIDAY NIGHTS.

DRIER WEATHER WILL FOLLOW LATE FRIDAY INTO THE WEEKEND...THOUGH A
FEW FLURRIES OR LIGHT SNOW SHOWERS ARE NOT OUT OF THE QUESTION.
TEMPERATURES...HOWEVER...WILL BE SLOW TO MODERATE...THOUGH WE MAY
SEE DOWNSLOPE BREEZES FINALLY MATERIALIZE BY THE SECOND HALF OF
THE WEEKEND...AND THIS SHOULD HELP PUSH TEMPERATURES ABOVE THE
FREEZING MARK...AND INTO THE 40S IN SPOTS. A WEAKER...THOUGH
LIKELY DRY COLD FRONT...MAY FOLLOW LATE SUNDAY AS ANOTHER EMBEDDED
UA DISTURBANCE EMERGES TO OUR NORTH. THIS MAY AT LEAST BRIEFLY
TEMPER WARMING INTO EARLY NEXT WEEK.

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        37  70  30  62  25 /   0   0   0   0  30
TULIA         34  71  29  56  25 /   0   0   0   0  30
PLAINVIEW     36  73  31  60  27 /   0   0   0   0  40
LEVELLAND     36  75  39  69  33 /   0   0   0   0  40
LUBBOCK       37  75  37  66  31 /   0   0   0   0  40
DENVER CITY   36  74  45  72  40 /   0   0   0   0  40
BROWNFIELD    36  75  42  72  35 /   0   0   0   0  40
CHILDRESS     37  78  35  47  25 /   0   0   0   0  50
SPUR          39  78  37  58  29 /   0   0   0   0  50
ASPERMONT     40  77  40  59  30 /   0   0   0   0  50

&&

.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

$$

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