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000 FXUS64 KHGX 222320 AFDHGX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 520 PM CST SUN NOV 22 2009 .DISCUSSION... SEE AVIATION DISCUSSION BELOW. && .AVIATION... VFR THIS EVENING BUT AM EXPECTING PATCHY FOG DEVELOPING BETWEEN 06-09Z ACROSS THE TAF SITES. FOG SHOULD BE SHALLOW AND BURN OFF QUICKLY AROUND 14Z. WINDS WILL BECOME E-SE ON MONDAY BUT OVERALL SKY CONDITIONS WILL REMAIN VFR. 43 && .PREV DISCUSSION... /ISSUED 304 PM CST SUN NOV 22 2009/ DISCUSSION... SFC HIGH ACROSS SE TX THIS AFTN RESULTING IN VERY PLEASANT WEATHER WITH LOTS OF SUNSHINE AND MILD TEMPERATURES. THE COMBINATION OF CLEAR SKIES...LIGHT SOUTHERLY WINDS IN THE BOUNDARY LAYER...AND WET GROUND CONDITIONS WILL RESULT IN A VERY FAVORABLE SETUP FOR FOG DEVELOPMENT TONIGHT. HAVE PLACED DENSE FOG IN THE FORECAST FOR ALL OF SE TX IN THE 06-15Z TIME FRAME. WILL LIKELY NEED AN ADVISORY FOR PORTIONS OF THE AREA BUT WILL DEFER TO EVENING SHIFT TO MAKE THIS DECISION. ONCE THE FOG BURNS OFF MONDAY WILL BE ANOTHER VERY NICE DAY. EXPECT LOTS OF SUNSHINE AND MILD TEMPERATURES...WITH A FEW CLOUDS DEVELOPING IN THE AFTN AS LOW LEVEL MOISTURE BEGINS TO SLOWLY RETURN. UPPER LOW IS FORECAST TO DEVELOP ACROSS THE CENTRAL PLAINS LATE MONDAY INTO TUESDAY WITH ASSOCIATED PACIFIC COLD FRONT PUSHING THROUGH THE AREA TUESDAY. FLOW ALOFT WILL BECOME MORE DIFFLUENT MONDAY NIGHT/TUESDAY MORNING...BUT BEST JET DYNAMICS REMAIN WELL NORTH. MOISTURE RETURN IS FORECAST TO BE FAIRLY MODEST AHEAD OF THE FRONT AS THE LOW LEVEL JET NEVER GETS FULLY ESTABLISHED. PWS WILL INCREASE TO 1.1-1.3 INCHES. CLOUDS WILL FILL IN MONDAY NIGHT WITH A FEW STREAMER SHOWERS DEVELOPING MAINLY AFTER MIDNIGHT. WILL HAVE 40-60 POPS BLANKETED AREA WIDE TUESDAY. HIGHEST POPS WILL BE OVER COASTAL ZONES/OFFSHORE WHERE SLIGHTLY HIGHER PWS ARE FORECAST. THE LATEST NAM/ECMWF RUNS CONTINUE TO BE 3 TO 6 HOURS SLOWER THAN THE GFS WITH THE TIMING OF THE FRONT...NOT HAVING IT OFF THE COAST UNTIL LATE AFTN. HAVE KEPT PRECIP GOING INTO THE EARLY EVENING FOR COASTAL ZONES AS A RESULT. EXPECT MOSTLY LIGHT SHOWERS WITH SOME EMBEDDED THUNDER. SKIES WILL CLEAR RAPIDLY TUESDAY EVENING IN THE WAKE OF THE FRONT. FOLLOWING THE FROPA...NICE WEATHER IS EXPECTED FOR THE THANKSGIVING HOLIDAY PERIOD (WEDNESDAY THROUGH SATURDAY). FLOW ALOFT BECOMES NORTHERLY WITH SFC HIGH BEING REINFORCED BY A COUPLE OF DRY FRONTAL PASSAGES. EXPECT GENERALLY CLEAR SKIES WITH LOWS IN THE 40S AND HIGHS IN THE 60S. MINS IN THE 30S WILL LIKELY OCCUR IN RURAL AREAS OVER THE NE ZONES...WITH THURSDAY NIGHT LOOKING LIKE THE COOLEST NIGHT. MEDIUM RANGE MODELS CONTINUE TO SHOW A LOT OF DIFFERENCES NEXT WEEKEND...WITH ECMWF FORECASTING THE DEVELOPMENT OF A STRONG UPPER LOW WEST OF THE STATE AND GFS SHOWING A CONTINUED NW FLOW ALOFT. FOR NOW HAVE LEANED TOWARD THE DRIER 12Z GFS WHICH HAS SUPPORT OF THE ENSEMBLE MEAN. GIVEN THIS SOLUTION A WEAK FRONT IS EXPECTED TO PASS THROUGH SUNDAY...AND HAVE 20 POPS IN THE FORECAST FOR THIS. 35 MARINE... QUIET/MOSTLY CALM CONDITIONS FOR THE COASTAL WATERS THE NEXT DAY OR SO WITH HIGH PRESSURE AS THE MAIN INFLUENCE. AS THE HIGH MOVES EAST OF THE AREA...ONSHORE WINDS TO RETURN TOMORROW. OUR NEXT COLD FRONT STILL SLATED FOR TUE...BUT THERE ARE SOME SLIGHT TIMING DIFFERENCES (GFS JUST A TAD FASTER THAN NAM). BUT WE SHOULD SEE MODERATE/STRONG NY WINDS OVER THE COASTAL WATERS BY TUE NIGHT...ALONG WITH POSSIBLE SCA FLAGS. WIND SPEEDS SHOULD WEAKEN BY WED NIGHT BUT STAY FROM THE N/NE THROUGH THE REMAINDER OF THE WEEK. 41 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 48 74 54 66 44 / 0 0 30 40 10 HOUSTON (IAH) 48 74 57 72 45 / 0 0 20 40 10 GALVESTON (GLS) 55 71 63 74 53 / 0 0 20 50 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...39 AVIATION/MARINE...43