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000 FXUS64 KSJT 210931 CCA AFDSJT AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN ANGELO TX 331 AM CST SAT NOV 21 2009 .SHORT TERM... MUCH OF THE MID/UPPER CLOUDINESS OVER THE BIG COUNTRY AND HEARTLAND EARLY THIS MORNING WILL MOVE EAST OF THE REGION BY SUNRISE...AS UPPER LOW IN CENTRAL TEXAS ALSO MOVES EAST. WINDS WILL BE LIGHT AND VARIABLE EARLY THIS MORNING...BUT SHIFT TO THE SOUTH AT 5 TO 10 MPH...AS A WEAK LEE TROUGH DEVELOPS. WENT CLOSE TO GFS MOS GUIDANCE TODAY IN MIDDLE OF THE AIRMASS AND FULL SUN. GUIDANCE IS USUALLY CLOSE IN SUCH SITUATIONS. HOWEVER WENT LOWER THAN GUIDANCE TONIGHT....SOUTH OF THE BIG COUNTRY... WHERE GOOD NIGHTTIME RADIATIONAL CONDITIONS DEVELOP...ESPECIALLY IN LOW LYING AREAS AND RIVER VALLEYS. 04 .LONG TERM... THE FORECAST PATTERN IN THE LONG TERM CONTINUES TO LOOK DRY FOR OUR AREA. TEMPERATURES SUNDAY WILL BE WARMER THAN TODAY. LOWS SUNDAY NIGHT WILL ALSO NOT BE AS COOL. BOUNDARY LAYER SHOULD STAY MIXED ACROSS OUR NORTHERN COUNTIES...AND LOW CLOUD DEVELOPMENT/ ADVANCEMENT IS INDICATED BY EARLY MONDAY MORNING ACROSS MUCH OF THE AREA SOUTH OF INTERSTATE 20. HIGHS MONDAY ARE EXPECTED TO BE AROUND 10 DEGREES ABOVE NORMAL WITH SOME THERMAL RIDGING INDICATED AHEAD OF APPROACHING COLD FRONT. OVERALL...THE GFS AND ECMWF MODELS INDICATE THAT AN UPPER TROUGH WILL DEEPEN INTO THE NORTHERN/CENTRAL PLANIS MONDAY...WITH AN UPPER LOW AND TROUGH PROGRESSING TOWARD THE MID-MISSISSIPPI VALLEY ON TUESDAY. THOUGH THE GFS AND ECMWF STILL HAVE SOME DIFFERENCES WITH TIMING AND PLACEMENT...BOTH MODELS SHOW THE ASSOCIATED COLD FRONT DROPPING SOUTH ACROSS WEST CENTRAL TEXAS MONDAY NIGHT. WILL BE A DRY COLD FRONTAL PASSAGE FOR OUR AREA...REGARDLESS OF THE SPECIFIC MODEL DIFFERENCES. COOLER AIRMASS WILL FOLLOW THIS FRONTAL PASSAGE AND RESIDE IN OUR REGION TUESDAY. WEDNESDAY AND THURSDAY...THE GFS IS MORE AGGRESSIVE IN DIVING ANOTHER SHORTWAVE INTO THE MIDWEST AND CARVING OUT A DEEP TROUGH INTO THE EASTERN PART OF THE COUNTRY BY LATE NEXT WEEK. DEPENDING ON HOW THIS PATTERN EVOLVES...MAY SEE A REINFORCING SURGE OF COOLER AIR INTO OUR AREA. APPEARS AT THIS TIME...HOWEVER...THAT THE BULK OF THE COLD AIR ADVECTION WOULD BE TO OUR NORTHEAST AND EAST. 19 && .PRELIMINARY POINT TEMPS/POPS... ABILENE 65 44 71 47 76 / 0 0 0 0 0 SAN ANGELO 67 42 73 47 76 / 0 0 0 0 0 JUNCTION 66 36 73 46 74 / 0 0 0 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$