000
FXUS64 KLUB 180317
AFDLUB

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LUBBOCK TX
1017 PM CDT THU APR 17 2014

.UPDATE...
TEMPS CONTINUE TO FALL TONIGHT AS DEWPOINTS SLOWLY RISE. WITH WINDS
COMMENCING TO VEER TO A MORE UPSLOPE WIND COMPONENT...LOW LEVEL
MOISTURE WILL CONTINUE TO BE ON THE RISE...LEADING TO THE
POTENTIAL FOR FOG DEVELOPMENT. KCDS HAS DROPPED BELOW
10SM...THOUGH STILL VFR BUT THIS IS SUGGESTIVE OF FOG POTENTIAL
OVERNIGHT. HAVE THEREFORE INSERTED PATCHY FOG INITIALLY ACROSS
THE ROLLING PLAINS...THEN EXPANDING IT TO THE SOUTH PLAINS
OVERNIGHT INTO EARLY TOMORROW MORNING.

&&

.PREV DISCUSSION... /ISSUED 622 PM CDT THU APR 17 2014/

AVIATION...
KLBB CLOUD DECKS HAVE RISEN TO VFR CRITERIA EARLY THIS
EVENING WITH KCDS DROPPING BACK DOWN TO MVFR. WINDS VEERING TO
THE EAST SOUTHEAST TONIGHT WILL PROMOTE THE FILTERING OF LOW LEVEL
MOISTURE AND THE LIKELIHOOD OF THE RETURN OF MVFR CLOUDS AT KLBB.
FURTHERMORE...COMPUTER MODELS HINT AT THE POTENTIAL FOR FOG. THE
DEVELOPMENT OF FOG/HAZE HAPPENED EARLIER THIS MORNING/AFTN AT BOTH
TAF SITES...AND WITH LIGHT EAST SOUTHEAST WINDS OCCURRING
TONIGHT...THE RETURN OF FOG IS PLAUSIBLE. HAVE ADDED MVFR VIS FOR
FOG AT BOTH TAF SITES ATTM. TOMORROW MID- MORNING ANY LINGERING
LOW CLOUDS/FOG WILL SCOUR OUT AS WINDS RETURN TO A SRLY FLOW.

PREV DISCUSSION... /ISSUED 310 PM CDT THU APR 17 2014/

SHORT TERM...
UPPER TROUGH MOVING ACROSS THE ERN PANHANDLE. LOOP OF WATER VAPOR
IMAGERY APPEARS TO BE SHOWING STILL A BIT OF JET ENERGY DIGGING INTO
THE BASE OF THE TROUGH WITH SOME MID LEVEL ENHANCEMENT OVER THE LOW
LEVEL MOISTURE IN PLACE ACROSS THE ROLLING PLAINS. SOME LIGHT PRECIP
THAT AREA PER KCDS METAR...A FEW WEST TEXAS MESONET STATIONS...AND
AREA RADARS. TIMING PER SATELLITE IMAGERY SUPPORTS MODEL SOLUTION
SHIFTING LIGHT PRECIP EAST OF THE FCST AREA BY 00Z AND WILL KEEP
POPS JUST BELOW 15 PCT ATTM.

SOME DRY ADVECTION COMING INTO THE NRN AND WRN ZONES BUT LOW LEVEL
MOISTURE HANGING ON ACROSS THE EAST. WITH MODELS SHOWING WINDS
SHIFTING FAIRLY QUICKLY TO THE EAST AND SOUTHEAST...WOULD EXPECT
THIS MOISTURE TO EITHER HANG IN OR RETURN FAIRLY QUICKLY IF IT DOES
GET SHUNTED TO THE EAST AND SOUTHEAST THIS MORNING. AS A RESULT
SHOULD SEE SOME LOW CLOUDS AND/OR FOG DEVELOP OVERNIGHT.

FRIDAY LOOKS QUIET ATTM. PROSPECT OF SOME MORNING CLOUDINESS BUT
WITH CLEARING DURING THE AFTN AS SHORT WAVE RIDGING BUILDS OVERHEAD.
PATTERN WILL FAVOR WARMER TEMPS. 12Z MOS SHOWING THE MAGNITUDE OF
THE WARMING ABOUT 10 DEGREES OVER TODAY WITH POSSIBILITY OF WARMER
DEPENDING IN PART OF TIMING AND DEGREE OF CLEARING.

LONG TERM...
RAIN CHANCES CONTINUE TO HOLD ON FOR THIS WEEKEND THO TIMING AND
COVERAGE SEEM TO BE THE BIGGEST DIFFERENCES BETWEEN MODELS. THEY DO
SEEM TO HAVE A CONSENSUS THAT PRECIP/CONVECTION WILL HOLD OFF UNTIL
AFTER SUNRISE SATURDAY. FROM THERE MODELS ARE SPLIT ON WHEN
CONVECTION WILL START WITH THE NAM FIRING CONVECTION STARTING ALONG
THE TX/NM STATE LINE AROUND LATE MORNING...THE GFS WAITING UNTIL
LATE EVENING...AND THE ECMWF STARTING AROUND 12Z SATURDAY MORNING.
FOR NOW I HAVE GONE WITH THE /SLOWER/ TIMES AND HAVE KEPT CHANCE POP
IN OUR WESTERN TWO THIRDS ZONES WITH THE HIGHEST CHANCES BEING THE
CENTRAL AND SOUTHERN SOUTH PLAINS. CAPE OVER 500 J/KG WILL BE
HELPFUL WITH AIDING CONVECTION DEVELOPMENT. THE LARGEST CAPE VALUES
WILL BE IN THE SOUTHERN SOUTH PLAINS INTO THE PERMIAN BASIN WHICH IS
WHERE THE HEAVIEST ACTIVITY IS EXPECTED. FORECAST SOUNDINGS SUGGEST
THAT STORMS THAT DEVELOP SHOULD NOT BECOME SEVERE AS THEY SHOW MOIST
ATMOSPHERIC PROFILES WITH PWATS OVER 1 INCH AND NO SHEAR OF ANY
SIGNIFICANCE. SOME STORMS HOWEVER MAY PRODUCE STRONG GUSTY WINDS
ESPECIALLY AS THEY DECAY. THE NAM DISSIPATES CONVECTION QUICKLY
OVERNIGHT BEFORE HAVING AN ENCORE SUNDAY EVENING AS IT PUSHES A
FRONT/DRYLINE THROUGH. MOST MODELS WITH THE EXCEPTION OF THE GFS
HINT AT SUCH HAPPENING...HOWEVER THE NAM IS THE MOST AGGRESSIVE. FOR
THE TIME BEING I HAVE KEPT POPS IN THE 30 TO 40 RANGE SATURDAY
AFTERNOON AND EVENING AND TAPER THEM OFF BY SUNDAY AFTERNOON. THE
ONLY REASON I HAVE NOT GONE HIGHER WITH POPS IS DUE TO TIMING
UNCERTAINTY. I HAVE RAISED POPS SUNDAY EVENING TO JUST BELOW MENTION
FOR A SECOND PASS OF THUNDERSTORMS BUT AM RELUCTANT TO GO HIGHER
GIVEN THE UNCERTAINTY THAT IT WILL HAPPEN. HOPEFULLY THE OUTCOME
WILL BE MORE CLEARER TOMORROW AND I CAN ACT ACCORDINGLY.

BEYOND THE WEEKEND...AN UPPER LEVEL RIDGE WILL MOVE OVERHEAD QUICKLY
ON TUESDAY AHEAD OF ANOTHER UPPER LEVEL WAVE THAT IS PUSHING
EASTWARD ALONG THE US/CANADA BORDER. A LEE TROF WILL DEVELOP BY TUESDAY
EVENING DEVELOPING A DRYLINE. THE GFS IS A BIT MORE AGGRESSIVE THAN
THE ECMWF WITH TRYING TO FIRE CONVECTION ALONG THE DRYLINE AND
FAVORS DEVELOPMENT OFF THE CAPROCK WHERE MOISTURE IS MORE READILY
AVAILABLE. FOR NOW I HAVE KEPT POPS LOW AS THE EVOLUTION OF THIS HAS
NOT BEEN CONSISTENT EXCEPT FOR THE ECMWF WHO HAS STAYED ON THE DRY
SIDE. IF ANYTHING WILL COME OUT OF THIS IT WILL BE WIND AND PROBABLY
DUST. TEMPS WILL GRADUALLY WARM THROUGH THE WEEK REACHING THE MID
80S TO LOW 90S BY THURSDAY. ALDRICH

&&

.PRELIMINARY POINT TEMPS/POPS...
FRIONA        41  72  49  75  48 /   0   0  20  40  30
TULIA         43  73  50  75  50 /   0   0  10  40  30
PLAINVIEW     42  73  51  74  51 /   0   0  10  40  30
LEVELLAND     42  72  53  73  52 /   0   0  20  40  40
LUBBOCK       44  72  53  74  53 /   0   0  10  40  40
DENVER CITY   44  72  53  73  54 /   0   0  20  40  40
BROWNFIELD    43  73  54  74  54 /   0   0  20  40  40
CHILDRESS     47  73  52  77  55 /  10   0  10  40  40
SPUR          45  74  53  76  55 /  10   0  10  40  40
ASPERMONT     49  75  53  79  57 /  10   0  10  40  40

&&

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

$$

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