AFDHOU SOUTHEAST TEXAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX 423 AM CDT MON SEP 1 2003 ...INCREASING THREAT OF SOME FLOODING THIS EARLY MORNING ACROSS COASTAL AND EASTERN PORTIONS OF SOUTHEAST TEXAS... SHOWERS AND THUNDERSTORMS HAVE DEVELOPED SINCE MIDNIGHT ACROSS THE COASTAL COUNTIES OF SOUTHEAST TEXAS WHERE STRONG CONVERGENCE EXISTS. VERY DEEP TROPICAL MOISTURE (PRECIP WATER VALUES APPROACHING 2.50 INCHES!) IS LEADING TO SOME HEFTY RADAR ESTIMATED RAINFALL TOTALS IN THESE AREAS WITH ACTIVITY BEGINNING TO BUILD FURTHER INLAND MAINLY EAST THROUGH NORTHEAST OF THE HOUSTON AREA. SIGNIFICANT TRAINING HAS ALSO BEEN OCCURING ACROSS COASTAL MATAGORDA AND BRAZORIA COUNTIES... AND IT APPEARS THAT THIS HEAVY RAIN THREAT IS BEGINNING TO SHIFT A LITTLE TO THE EAST ACROSS GALVESTON AND HARRIS COUNTIES. THE HARDEST HIT AREAS YESTERDAY...CHAMBERS AND LIBERTY COUNTIES...MAY SOON SEE SOME MORE RAIN. SATELLITE LOOPS SHOW COOLING CLOUD TOPS EXPANDING NORTHWARD INTO SOUTHEAST TEXAS. RADAR LOOPS SHOW CONVECTION EXTENING ALL THE WAY DOWN THE TEXAS COAST TO EAST OF BAFFIN BAY. FLOOD THREAT IS SIGNIFICANT EARLY THIS MORNING...AND WILL HAVE THE FLOOD WATCH IN EFFECT FOR ALL OF SOUTHEAST TEXAS TODAY. ALTHOUGH THERE IS NOT MUCH GOING ON RIGHT NOW NORTH AND WEST OF THE HOUSTON AREA...BELIEVE THE THREAT FOR HEAVY RAINFALL WILL EXIST LATER THIS MORNING AND ON INTO THE AFTERNOON...ESPECIALLY IF DAYTIME HEATING CAN ESTABLISH ITSELF. RAINFALL TOTALS COULD AVERAGE 1 TO 3 INCHES WITH ISOLATED 4 TO 6 INCH AMOUNTS POSSIBLE BEFORE THE DAY COMES TO AN END. DEEP MOISTURE LEVELS AND THE THREAT FOR PERIODS OF MORE RAIN SHOULD CONTINUE INTO TONIGHT AND TOMORROW. ONCE AGAIN...HARD TO PINPOINT EXACTLY WHERE GREATEST RAIN CHANCES WILL BE. WILL LET THE DAY CREW TRY TO FIGURE THAT ONE OUT. GOOD NEWS IS THAT MODELS ARE BEGINNING TO AGREE ON A STRONG ENOUGH EASTERN U.S. UPPER TROUGH THAT WILL DRY OUT OUR AREA FOR THE UPCOMING WEEKEND. WILL GO AHEAD AND TAKE THE RAIN OUT OF SATURDAY AND SUNDAY AND CALL FOR SLIGHTLY COOLER MORNING LOW TEMPERATURES. THIS COULD ACTUALLY BE OUR FIRST COLD FRONT OF THE UPCOMING FALL SEASON. HELLO SEPTEMBER! THANKS AGAIN TO LCH FOR COORDINATION CALL. 42/46/34 .HGX...FLOOD WATCH ALL OF SOUTHEAST TEXAS TODAY. SCEC 00-60 NM WATERS. PRELIMS... CLL TT 084/072 089/072 091 656 IAH TT 085/074 090/073 091 856 GLS TT 086/078 088/079 088 956 --------------------------------------------------------------------- .PREVIOUS DISCUSSION (144 AM CDT)... HAVE DECIDED TO GO AHEAD AND EXTEND THE FLOOD WATCH BACK DOWN TO THE COAST DUE TO THE CURRENT FLARE UP (SEE FFAHGX). SOME LOCATIONS ACROSS OUR UPPER TEXAS COASTAL COUNTIES RECEIVED BETWEEN 4 AND 12 INCHES OF RAIN YESTERDAY...AND IT WILL NOT TAKE A WHOLE LOT MORE TO LEAD TO FLOODING. THE FLOOD WATCH IS IN EFFECT FOR TODAY FOR ALL OF SOUTHEAST TEXAS. THANKS LCH FOR COORDINATION. 42/46 --------------------------------------------------------------------- .PREVIOUS DISCUSSION (114 AM CDT)... DID A ZONE UPDATE TO RAISE COASTAL COUNTY POPS AND MAKE A COUPLE OTHER 1ST PERIOD ADJUSTMENTS. MONITORING DEVELOPING CONVECTION ACROSS THE COASTAL COUNTIES AND OVER THE ADJACENT COASTAL WATERS. FAST STORM MOTION IS KEEPING RAINFALL TOTALS SO FAR ON THE LIGHT SIDE... BUT WILL HAVE TO WATCH IF SIGNIFICANT TRAINING DEVELOPS. MAY NEED TO RECONFIGURE THE FLOOD WATCH A LITTLE FURTHER SOUTH AND EAST IF THESE STORMS PERSIST OR INCREASE IN COVERAGE. A COASTAL WATERS FORECAST UPDATE WAS ALSO MADE. 42/46