000 WTPZ45 KNHC 081501 TCDEP5 TROPICAL STORM JOVA DISCUSSION NUMBER 11 NWS NATIONAL HURRICANE CENTER MIAMI FL EP102011 800 AM PDT SAT OCT 08 2011 CONVENTIONAL AND MICROWAVE SATELLITE DATA INDICATE JOVA HAS BEEN DRIFTING NORTHWARD DURING THE PAST 9 HOURS OR SO. NOW THAT THE NOCTURNAL BURSTING PATTERN HAS SUBSIDED...THE CENTRAL DEEP CONVECTION APPEARS TO HAVE SETTLE INTO A CDO PATTERN...WITH A SMALL RING OF OVERSHOOTING CLOUD TOPS ENCIRCLING THE LOW-LEVEL CENTER. ALTHOUGH A 08/0947Z AMSU OVERPASS DID NOT SHOW MUCH MEAT ON THE BONES IN TERMS OF CENTRAL DEEP CONVECTION...THE CONVECTION SINCE THAT TIME APPEARS TO HAVE INCREASED. THE INITIAL INTENSITY IS RAISED TO 60 KT BASED ON A BLEND OF DVORAK SATELLITE INTENSITY ESTIMATES OF T3.5/55 KT FROM TAFB AND T4.0/65 KT FROM SAB...AND A 2-HR UW-CIMSS ADT AVERAGE OF T3.7/59 KT. THE INITIAL MOTION ESTIMATE IS 045/03 KT. JOVA IS LOCATED ON THE SUBTROPICAL RIDGE WHOSE AXIS LIES ALONG 16N LATITUDE. AS A RESULT OF THE WEAK STEERING FLOW IN THIS AREA...PLUS SOME BINARY INTERACTION WITH HURRICANE IRWIN LOCATED TO THE WEST...JOVA IS EXPECTED TO DRIFT SLOWLY TO THE NORTHEAST OR EAST-NORTHEAST FOR THE NEXT 12 HOURS OR SO. AFTER THAT...ALL OF THE GLOBAL AND REGIONAL MODELS ARE IN EXCELLENT AGREEMENT THAT A BROAD MID-/UPPER-LEVEL TROUGH...NOTED JUST NORTH OF 20N LATITUDE IN WATER VAPOR IMAGERY... WILL CONTINUE TO DROP SLOWLY SOUTHWARD AND FORCE THE CYCLONE ON A MORE EASTWARD TRACK THROUGH 48 HOURS. BY 72 HOURS AND BEYOND...A SECONDARY TROUGH IS FORECAST TO DROP SOUTHWARD BEHIND THE FIRST TROUGH AND GRADUALLY LIFT OUT JOVA TO THE NORTHEAST. WHILE THERE REMAINS SOME DIFFERENCES IN FORWARD SPEED IN THE LATTER FORECAST PERIODS...THE OVERALL TREND OF THE MODEL GUIDANCE HAS BEEN TO CONVERGE ON LANDFALL ACROSS SOUTHWESTERN MEXICO IN THE 84 TO 96 HOUR TIME FRAME. THE OFFICIAL FORECAST TRACK IS SIMILAR TO BUT A LITTLE SOUTH AND EAST OF THE PREVIOUS TRACK...BUT STILL LIES TO THE NORTH AND WEST OF THE NHC CONSENSUS MODELS TVCN AND TVCA. JOVA IS EXPECTED TO REMAIN IN A MODERATE VERTICAL SHEAR REGIME FOR ANOTHER 12 HOURS OR SO. AFTER THAT...ENVIRONMENTAL CONDITIONS APPEAR FAVORABLE FOR STRENGTHENING...POSSIBLY EVEN FOR RAPID INTENSIFICATION...RIGHT UP UNTIL LANDFALL. THE GFS-BASED SHIPS GUIDANCE APPEARS TO BE CONTAMINATED BY UPPER-LEVEL WARMING CREATED IN THE MODEL AS IT STRENGTHENS JOVA. LIKEWISE...THE STRONG VERTICAL SHEAR SHOWN IN THE MODEL IS LIKELY DUE TO ENHANCED OUTFLOW THAT DEVELOPS TO THE NORTHEAST OF THE CYCLONE BY 48 HOURS. IT IS WORTH NOTING THAT BOTH THE HWRF AND GFDL MODELS MAKE JOVA A CATEGORY 4 HURRICANE PRIOR TO LANDFALL. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE PREVIOUS ADVISORY AND REMAINS WELL ABOVE STATISTICAL GUIDANCE AND THE INTENSITY CONSENSUS. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 15.8N 110.4W 60 KT 70 MPH 12H 09/0000Z 16.0N 109.6W 65 KT 75 MPH 24H 09/1200Z 16.1N 108.6W 70 KT 80 MPH 36H 10/0000Z 16.2N 107.5W 80 KT 90 MPH 48H 10/1200Z 16.5N 106.5W 90 KT 105 MPH 72H 11/1200Z 18.3N 105.3W 95 KT 110 MPH 96H 12/1200Z 21.5N 104.5W 30 KT 35 MPH...INLAND 120H 13/1200Z...DISSIPATED $$ FORECASTER STEWART