FXCA62 TJSJ 122205 RRA AFDSJU AREA FORECAST DISCUSSION...DELAYED NATIONAL WEATHER SERVICE SAN JUAN PR 605 PM AST SUN OCT 12 2008 .DISCUSSION...ADMITTEDLY ACTIVE WEATHER WAS SLOWER TO ARRIVE THAN ORIGINALLY EXPECTED TODAY...BUT IS CURRENTLY EXPANDING ACROSS THE LOCAL ISLANDS AND IT STILL APPEARS THAT AN EXTENDED PERIOD OF ACTIVE WEATHER IS ON TAP FOR THE FA. THE ACTIVE TROPICAL WAVE AND ITS ASSOCIATED AREA OF DISTURBED WEATHER...WITH AXIS LOCATED OVER PUERTO RICO LATE THIS AFTERNOON...WILL CONTINUE MOVING SLOWLY WEST NORTHWEST ACROSS THE REMAINDER OF THE LOCAL AREA TONIGHT THROUGH MONDAY. ASSOCIATED SURFACE CIRCULATION NEAR 15.3 NORTH AND 68 WEST CONTINUES TO BECOME A LITTLE BETTER ORGANIZED AND MAY BECOME MORE OF A FACTOR LOCALLY DURING THE NEXT FEW DAYS...AS RATHER COMPLEX WEATHER PATTERN CONTINUES TO UNFOLD FOR THE LOCAL AREA TONIGHT THEN PROBABLY CONTINUES TO VARYING DEGREES THROUGH MOST OF THE UPCOMING WORK WEEK. LATEST MODEL GUIDANCE HAVE AGAIN TWEAKED THEIR SOLUTIONS...BUT STILL INDICATING AN EXTENDED PERIOD OF ACTIVE WEATHER...WITH WHAT NOW APPEARS TO BE A BETTER POTENTIAL FOR TROPICAL LOW DEVELOPMENT WITH AFOREMENTIONED SURFACE CIRCULATION TO OUR SOUTH OR SOUTHWEST DURING THE NEXT DAY OR SO...AND THEN POSSIBLY MOVING "BACK" TO THE NORTHEAST ACROSS THE LOCAL ISLANDS DURING THE TUESDAY THROUGH THURSDAY TIME FRAME. WITH TROPICAL WAVE AND ASSOCIATED DEEP TROPICAL MOISTURE NOW BEGINNING TO AFFECT THE LOCAL AREA...AND COMBINING WITH CONTINUED FAVORABLE UPPER LEVEL VENTILATION AND LOCAL EFFECTS...TONIGHT AND EARLY MONDAY LOOK QUITE ACTIVE WITH SHOWERS AND THUNDERSTORMS IN BANDS...HEAVY RAINFALL AND GUSTY WINDS DESTINED TO AFFECT MOST OF THE LOCAL ISLANDS DURING THIS TIME. AS "BURSTY" HEAVY RAINFALL PERSISTS IN SOME AREAS...FLASH FLOOD POTENTIAL WILL GRADUALLY BE INCREASING...AND A FLASH FLOOD WATCH REMAINS IN EFFECT FOR ALL BUT THE WESTERN THIRD OF PUERTO RICO THROUGH 8 PM...AND WILL BE EXTENDED AND POSSIBLY EXPANDED OR RE-ARRANGED FOR LATER TONIGHT THROUGH MONDAY OR LONGER. AN EARLY ESTIMATE ON RAINFALL FOR TONIGHT THROUGH EARLY MONDAY...WOULD BE A GENERAL 2 TO 5 INCHES WITH LOCALLY HIGHER AMOUNTS. FOR MONDAY THROUGH WEDNESDAY AND PROBABLY THURSDAY...WE EXPECT AN EXTENDED PERIOD OF UNSETTLED WEATHER...WITH EXACT DETAILS VERY DEPENDENT ON HOW MUCH TROPICAL SYSTEM DEVELOPS OR NOT AND HOW IT MOVES. AT THIS MOMENT...FORECAST IS BASED ON A MODEL CONSENSUS OF GENERAL SURFACE LOW PRESSURE ACROSS THE CENTRAL AND EASTERN CARIBBEAN...MOVING LITTLE OR EVEN A BIT ERRATICALLY...BUT GENERALLY REMAINING IN A LOCATION THAT ALLOWS DEEP TROPICAL MOISTURE TO CONTINUE TO BE ADVECTED ACROSS THE LOCAL ISLANDS... INTERACTING WITH LOCAL EFFECTS AND CONTINUED FAVORABLE UPPER LEVEL VENTILATION...TO PRODUCE PERIODS OF SHOWERS AND THUNDERSTORMS WITH HEAVY RAINFALL ACROSS THE FA. SO...AGAIN...CURRENT SET-UP AND CONTINUING MODEL SOLUTIONS DO INDICATE...YET AGAIN...THE "INCREASING LIKELIHOOD" OF MANY DAYS OF VERY ACTIVE WEATHER LOCALLY...WITH SHOWERS AND THUNDERSTORMS...AND INCREASING POTENTIAL FOR HEAVY RAINFALL AND FLOODING. UNFORTUNATELY...AS WE HAVE BEEN ADVERTISING...LATEST SIGNS STILL INDICATE THAT SOME AREAS AFFECTED BY THE HISTORICAL HEAVY RAINFALL AND CATASTROPHIC FLASH AND RIVER FLOODING OF 9/21-9/23...WILL LIKELY BE AFFECTED AGAIN. && .HYDROLOGY...ALTHOUGH EVENT STARTED SLOWLY TODAY...OUR INITIAL "SEVERAL DAY" FORECAST THINKING HAS CHANGED LITTLE...WITH "POTENTIAL" STORM TOTAL RAINFALL AMOUNTS OF AT LEAST 15 INCHES...WITH SOME AREAS POSSIBLY RECEIVING 24 INCHES OR MORE! IF THIS SCENARIO CONTINUES TO UNFOLD...THE SITUATION WOULD BECOME VERY BAD...AND WE CONTINUE TO STRONGLY URGE ALL LOCAL RESIDENTS AND VISITORS TO CLOSELY MONITOR THE WEATHER TONIGHT THROUGH AT LEAST THURSDAY OF THIS UPCOMING WEEK. IN ADDITION...PEOPLE ARE REMINDED THAT IT DOES NOT NEED TO BE RAINING AT THEIR EXACT LOCATION...FOR DANGEROUS WATER SURGES TO OCCUR IN LOCAL STREAMS AND RIVERS. PEOPLE SHOULD STAY OUT OF THESE TYPE OF WATERS FROM TONIGHT THROUGH THE NEXT SEVERAL DAYS. && .AVIATION...GENERALLY POOR AVIATION CONDITIONS EXPECTED ACROSS MOST OF THE LOCAL ISLANDS AND AT MOST LOCAL TAF SITES DURING THE NEXT FEW DAYS. CONDITIONS BEGINNING TO DETERIORATE AT THIS TIME ACROSS THE LOCAL CARIBBEAN...PARTS OF PUERTO RICO...CULEBRA... VIEQUES AND THE U.S. VIRGIN ISLANDS...AND WILL SPREAD ACROSS THE REMAINDER OF THE LOCAL AREA THROUGH THIS EVENING. INITIAL VFR CONDITIONS ON MUCH OF THE ATLANTIC SIDE OF THE LOCAL ISLANDS WILL STEADILY WORSEN TO MVFR...WITH LOCAL IFR IN INCREASING SHOWERS AND THUNDERSTORMS WITH GUSTY WINDS. ON THE CARIBBEAN SIDE...EXPECT MOSTLY MVFR CONDITIONS WITH AREAS OF IFR CONDITIONS IN NUMEROUS TO WIDESPREAD SHOWERS AND SCATTERED THUNDERSTORMS. SURFACE WIND GUSTS OF 30 TO 35 KNOTS AND MOUNTAIN OBSCURATIONS WILL ALSO OCCUR. && .MARINE...ACTIVE WEATHER EXPECTED ACROSS THE REGIONAL WATERS DURING THE NEXT FEW DAYS...WITH INCREASING WINDS AND SEAS. FORECAST ADJUSTMENTS SHOULD BE EXPECTED...ESPECIALLY IF TROPICAL LOW PRESSURE CONTINUES TO DEVELOP TO THE SOUTH AND SOUTHWEST OF THE LOCAL AREA...MOVES LITTLE AND STRENGTHENS AS EXPECTED. A SMALL CRAFT ADVISORY IS IN EFFECT FOR AMZ732 AND THERE IS A PRECAUTIONARY STATEMENT FOR ALMOST ALL OF THE REMAINING LOCAL COASTAL WATERS. && .PRELIMINARY POINT TEMPS/POPS... SJU 77 85 77 86 / 70 50 50 80 STT 78 84 78 85 / 90 90 80 90 && .SJU WATCHES/WARNINGS/ADVISORIES... PR...FLASH FLOOD WATCH UNTIL 8 PM AST THIS EVENING FOR CENTRAL INTERIOR-CULEBRA-EASTERN INTERIOR-NORTH CENTRAL-NORTHEAST- PONCE AND VICINITY-SAN JUAN AND VICINITY-SOUTHEAST-VIEQUES. SMALL CRAFT ADVISORY AMZ732. VI...FLASH FLOOD WATCH UNTIL 8 PM AST THIS EVENING FOR ST CROIX-ST. THOMAS/ST. JOHN/ADJACENT ISLANDS. SMALL CRAFT ADVISORY AMZ732. && $$ BCS