000 FXUS62 KGSP 080721 AFDGSP AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 321 AM EDT MON SEP 8 2008 .SYNOPSIS... MOISTURE WILL BE ON THE INCREASE THROUGH TUESDAY OUT AHEAD OF AN APPROACHING COLD FRONT WHICH WILL MOVE THROUGH THE REGION BY WEDNESDAY. COOLER AND UNSETTLED WX WILL BE SEEN IN THE WAKE OF THIS FRONT THROUGH THE END OF THE WORKWEEK. && .NEAR TERM /THROUGH TONIGHT/... HIGH PRESSURE SLIDES OFF THE EAST COAST TODAY WITH SELY FLOW DEVELOPING ACROSS THE AREA AND BRINGING IN LOW LEVEL MOISTURE. THE SELY FLOW AND A LINGERING SFC BOUNDARY WILL PROVIDE LOW LEVEL FORCING WHILE A WEAK SHORT WAVE PROVIDES SOME MID LEVEL FORCING. OPS MODELS SHOW CAPE NEAR 1000 J/KG NORTH AND OVER 1500 J/KG SOUTH. SREF AGREES WITH CAPE OVER 1000 J/KG LIKELY. EXPECT SCT AFTERNOON STORMS FROM THE BLUE RIDGE WEST WITH THE BETTER LOW LEVEL FORCING AND ISOLATED EAST AND SOUTH OF THERE. ISOLATED SEVERE DOWNBURSTS CANNOT BE RULED OUT WITH DCAPE NEAR 750 J/KG AND SFC DELTA THETA E FROM 25 TO AS HIGH AS 35 ACROSS THE AREA. ABOVE NORMAL HIGHS ONCE AGAIN. TONIGHT LOW LEVEL MOISTURE REMAINS HIGH IN THE CONTINUED SLY FLOW. A COLD FRONT AND SHORT WAVE APPROACH THE AREA AS WELL. THAT SAID... BEST FORCING REMAINS TO OUR WEST. EXPECT SCT STORMS TO LINGER NEAR THE BLUE RIDGE IN THE EVENING WITH ISOLATED STORMS ELSEWHERE. PRECIP CHC SHIFTS TO THE MTNS WITH ISOLATED SHOWERS OVERNIGHT. LOWS WILL BE QUITE WARM WITH CLOUDS AND WARM AIR MASS. && .SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/... AS OF 230 AM MONDAY...LOOKS LIKE WE WILL BE REMAINING ON COURSE FOR INCREASING CVRG OF SHOWERS/TSTMS ON TUESDAY AS COLD FRONT AND ASSOCIATED FRONTAL BAND MOISTURE MOVES INTO THE CWFA. LATEST NAM FCST OF 0-6KM BULK SHEAR OF 30 KTS COULD BE SUPPORTIVE OF SVR STORMS...ESPECIALLY ACRS THE PIEDMONT LATER IN THE DAY AND INTO THE EVENING WITHIN PLUME OF MODERATE INSTABILITY WHICH DEVELOPS NORTHWARD. SOME DEGREE OF RESPONSE REMAINS ON BOTH THE LATEST OP GFS/NAM INTO THE NIGHT AS SLOW MOVING FRONT SAGS SOUTHEAST INTO THE FTHLS. ON WEDNESDAY...SFC HIPRES CENTER IS STILL FCST TO BUILD INTO THE NORTHEAST...LEADING TO DEVELOPING DAMMING REGIME INTO THE SOUTHERN APPALACHIANS. SE FLOW ABOVE DEVELOPING NE SFC WIND WILL COMBINE WITH LINGERING DEEP MOISTURE TO KEEP PCPN CHANCES FAIRLY HIGH INTO THE NIGHT. THE LATEST GFS AND ECMWF ARE SIMILAR IN THEIR DEPICTION OF THE POSITION AND MAGNITUDE OF LINGERING DAMMING REGIME INTO THURSDAY...AND BOTH WITH CONTINUED RESPONSE AND HIGH MEAN RH AS WELL. LEANING TOWARD NUDGING MAXES DOWNWARD AND PCPN CHANCES UPWARD. && .LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 230 AM MONDAY...EXPECTING AN INCREASE IN SOUTHERLY LLVL FLOW ON FRIDAY AS PARENT HIPRES TRANSLATES INTO THE NORTH ATLANTIC AND COLD FRONT APPROACHES FROM THE NORTHWEST. INHERITING SOLID CHANCE POPS FOR FRIDAY AND A RETURN TO NEAR NORMAL MAX TEMPS. IT IS NOT CONCLUSIVE AT THIS POINT WHETHER A SLOWER DAMMING EROSION WOULD OCCUR LEADING TO A LESS OPTIMISTIC TEMPERATURE CLIMB. WILL BASE THE WEEKEND FCST ON THE HPC/ECMWF SOLUTION ON LOW AMPLITUDE UPPER RIDGING OVER THE SOUTHEAST CONUS...A FRONTAL BNDRY WELL TO OUR NW AND IKE MOVING ACRS THE WESTERN GULF OF MEXICO. && .AVIATION /07Z MONDAY THROUGH FRIDAY/... FOG IS THE MAIN CONCERN OVERNIGHT AS GUIDANCE HAS BEEN HIT AND MISS. WILL GO WITH PERSISTENCE AND INCLUDE IT ONLY AT KAVL...WHERE THE CHANCE IS BEST...AND KCLT AND KHKY WHERE MOISTURE WILL BE A LITTLE HIGHER AND SURROUNDING SITES ARE ALREADY DROPPING. THERE IS THE POSSIBILITY OF A FEW SHOWERS OR THUNDERSTORMS THIS AFTERNOON. WILL LEAVE OUT OF TAFS FOR NOW SINCE TIMING AND LOCATION STILL IN QUESTION. HIGH CLOUDS WILL BE ON THE INCREASE THIS EVENING. LIGHT WINDS BECOME NORTHEASTERLY WITH MIXING THEN SOUTHEASTERLY THIS AFTERNOON. OUTLOOK...MORNING FOG IS POSSIBLE EACH DAY WHICH COULD RESULT IN A BRIEF PERIOD OF MVFR/IFR CONDITIONS. SCATTERED THUNDERSTORMS ON TUESDAY MAY RESULT IN TEMPORARY MVFR VISIBILITY/CEILING. BOTH WEDNESDAY AND THURSDAY LOOK UNSETTLED WITH SHOWERS AND STORMS MORE NUMEROUS. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...CSH NEAR TERM...RWH SHORT TERM...CSH LONG TERM...CSH/SBK AVIATION...RWH