000 FXUS64 KLUB 250542 AFDLUB AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LUBBOCK TX 1142 PM CST TUE NOV 24 2009 .AVIATION... ONLY AVIATION CONCERN IS THE TIMING OF A WEAK COLD FRONT THAT WILL MOVE THROUGH THE AREA TODAY. THE FRONT IS EXPECTED TO MOVE THROUGH KCDS AROUND 17-18Z AND THROUGH KLBB AROUND 20-22Z. THE WIND SHIFT FROM W-NW TO N-NE SHOULD BE GRADUAL...BUT DID INCREASE WIND SPEEDS TO 12 KTS FOR A PERIOD AT KCDS. OTHERWISE...VFR CONDITIONS WITH JUST A FEW CLOUDS ARE EXPECTED ABOUT 20K FT. && .PREV DISCUSSION... /ISSUED 539 PM CST TUE NOV 24 2009/ AVIATION... VFR CONDITIONS WILL CONTINUE THE NEXT 24 HRS. WINDS WILL BE LIGHT OVERNIGHT...TURNING WESTERLY WED MORNING BUT REMAINING UNDER 10 KTS. A WEAK NORTHERLY WIND SHIFT WILL MOVE INTO THE AREA LATE IN THE FORECAST...POSSIBLY INTO THE KCDS AREA BY 0Z THU. PREV DISCUSSION... /ISSUED 310 PM CST TUE NOV 24 2009/ SHORT TERM... COLD OVERNIGHT TEMPERATURES ARE EXPECTED. A DRY POST FRONTAL PAC/GREAT BASIN AIRMASS HAS CONTINUED TO SPILL OVER THE DIVIDE AND RIDGE SOUTHWARD INTO THE SOUTHERN PLAINS TODAY. AS SUCH...A 1025MB SURFACE HIGH WILL TRANSLATE ACROSS WEST TEXAS OVERNIGHT. THIS WILL BRING A PERIOD OF LIGHT/VARIABLE SURFACE WINDS AND WILL ALSO BE ACCOMPANIED BY SINGLE DIGIT DEWPOINTS AS NOW SEEN OVER NORTHEASTERN NEW MEXICO/WESTERN PANHANDLE/NORTHWESTERN SOUTH PLAINS. PROFILES CONTINUE TO SUGGEST A VERY DRY COLUMN THROUGH THE LOWER/MID TROP...WHICH WILL ALLOW FOR IDEAL RADIATIONAL COOLING. ALTHOUGH SOME THIN MOUNTAIN-INDUCED CIRRUS ARE STREAMING DOWNWIND OF THE COLORADO/NEW MEXICO ROCKIES WITHIN THE PERSISTENT NORTHWESTERLY FLOW ALOFT...CLOUDS WILL NOT INHIBIT COOLING. THUS HAVE CONTINUED TO DEPICT SUB-GUIDANCE TEMPERATURE MINIMA...RANGING FROM THE MID TEENS OVER THE NORTHWEST...TO THE MID/UPPER 20S EASTERN ROLLING PLAINS. CONTINUED NORTHWESTERLY FLOW ALOFT WILL OFFER NO MEANINGFUL CHANGE TO SOUTH PLAINS WEATHER FOR WEDNESDAY...ALTHOUGH SOME MODERATION IS EXPECTED. A NOTABLE SHORTWAVE TROUGH/UA LOW WILL DROP SOUTHEASTWARD OVER THE MID WEST...AND THIS FEATURE WILL PROMOTE ANOTHER SECONDARY PUSH OF INCREASING RIDGING/FRONT SOUTHWARD TOWARD THE SOUTH PLAINS BY WEDNESDAY EVENING. LONG TERM... A DAY OF FINE WEATHER WILL OCCUR ON THANKSGIVING DAY WITH MODELS CONTINUALLY SHOWING INCONSISTENCIES OVER THE HOLIDAY WEEKEND. A BREAK TO THE MOSTLY CLEAR SKIES WILL OCCUR ON FRIDAY AND SATURDAY AS A WEAK WAVE PASSES OVERHEAD ON FRIDAY. WITH AN INCREASING SURFACE PRESSURE AND HEIGHT GRADIENT...WINDS WILL BECOME BREEZY ON FRIDAY AND SATURDAY AHEAD OF A COLD FRONT. THIS MAY LEAD TO ELEVATED FIRE WEATHER CONDITIONS WITH VERY DRY AIR ACROSS WEST TEXAS. A COLD FRONT WILL MOVE THROUGH ON SATURDAY NIGHT OR SUNDAY MORNING. UNFORTUNATELY...THIS IS WHERE AGREEMENT AMONG MODELS COMES TO AN END. COLDER AIR AND LOW STRATUS MAY LEAD TO DAYTIME MAXIMA IN THE 40S ACROSS THE FA EARLY NEXT WEEK. REGARDING PRECIPITATION CHANCES...THE LATEST GFS RUN CAME IN MORE PROGRESSIVE AS WELL AS THE LATEST EUROPEAN RUN FROM THIS MORNING. THERE IS STILL CONSIDERABLE SPREAD IN THE GFS ENSEMBLE AND MOST MEMBERS DO INDICATE AN OPEN WAVE TROUGH RATHER THAN A CLOSED LOW SOLUTION. THEREFORE...WILL KEEP POPS UNCHANGED UNTIL MORE CONSISTENCY CAN BE NAILED DOWN IN THE MODEL SOLUTIONS. IF PRECIPITATION WERE TO OCCUR...SNOW OR A RAIN AND SNOW MIX WOULD BE SUPPORTED ON MONDAY MORNING GIVEN THE CURRENT FORECAST TEMPERATURES. JDV && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 33