Tropical Storm Fay Advisory 5 Plus Forecast Discussion

BULLETIN
TROPICAL STORM FAY ADVISORY NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062008
5:00 PM EDT SAT AUG 16 2008
FAY WEAKER BUT RE-ORGANIZING SOUTH OF EASTERN CUBA. NEW WARNINGS AND WATCHES
FOR CUBA...
AT 5 PM EDT, 21:00 UTC, THE GOVERNMENT OF CUBA HAS ISSUED A HURRICANE WATCH
FOR THE PROVINCES OF VILLA CLARA, CIENFUEGOS AND MATANZAS. A HURRICANE
WATCH REMAINS IN EFFECT FOR THE CUBAN PROVINCES OF CAMAGUEY, CIEGO DE AVILA
AND SANCTI SPIRITUS. A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE
POSSIBLE WITHIN THE WATCH AREA, GENERALLY WITHIN 36 HOURS.
AT 5 PM EDT, 21:00 UTC, THE GOVERNMENT OF CUBA HAS ISSUED A TROPICAL STORM
WARNING FOR THE PROVINCES OF CIEGO DE AVILA AND SANCTI SPIRITUS. A TROPICAL
STORM WARNING ALSO REMAINS IN EFFECT FOR THE CUBAN PROVINCES OF CAMAGUEY,
LAS TUNAS, HOLGUIN... GRANMA, SANTIAGO DE CUBA AND GUANTANAMO. A TROPICAL
STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE EXPECTED WITHIN THE
WARNING AREA WITHIN THE NEXT 24 HOURS.
AT 5 PM EDT, 21:00 UTC, THE GOVERNMENT OF THE BAHAMAS HAS CANCELED THE
TROPICAL STORM WARNING FOR THE TURKS AND CAICOS ISLANDS AND THE SOUTHEASTERN
BAHAMAS. ALSO AT 5 PM EDT, THE TROPICAL STORM WARNING FOR HAITI IS CANCELED
NORTH OF PORT-AU-PRINCE. A TROPICAL STORM WARNING REMAINS IN EFFECT FOR THE
SOUTHWESTERN PENINSULA OF HAITI.
A TROPICAL STORM WATCH REMAINS IN EFFECT FOR THE CENTRAL BAHAMAS, JAMAICA
AND THE CAYMAN ISLANDS.
INTERESTS IN WESTERN CUBA, THE FLORIDA KEYS AND THE FLORIDA PENINSULA SHOULD
MONITOR THE PROGRESS OF THIS SYSTEM. FOR STORM INFORMATION SPECIFIC TO YOUR
AREA, INCLUDING POSSIBLE INLAND WATCHES AND WARNINGS, PLEASE MONITOR
PRODUCTS ISSUED BY YOUR LOCAL WEATHER OFFICE.
AT 5:00 PM EDT, 21:00 UTC, THE CENTER OF TROPICAL STORM FAY WAS LOCATED NEAR
LATITUDE 19.3 NORTH, LONGITUDE 75.2 WEST, OR ABOUT 225 MILES, 365 KM
SOUTHEAST OF CAMAGUEY CUBA AND ABOUT 60 MILES, 100 KM SOUTH OF GUANTANAMO
CUBA. FAY IS MOVING TOWARD THE WEST NEAR 16 MPH, 26 KM/HR. A GRADUAL TURN
TOWARD THE NORTHWEST WITH A DECREASE IN FORWARD SPEED IS EXPECTED DURING THE
NEXT COUPLE OF DAYS. ON THIS TRACK, THE CENTER OF FAY WILL BE NEAR OR OVER
THE SOUTHERN COAST OF EASTERN AND CENTRAL CUBA TONIGHT AND SUNDAY AND NEAR
OR OVER WESTERN CUBA SUNDAY NIGHT OR MONDAY.
REPORTS FROM AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INDICATE THAT
FAY HAS WEAKENED SLIGHTLY. MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH, 65
KM/HR, WITH HIGHER GUSTS. STRENGTHENING IS FORECAST DURING THE NEXT COUPLE
OF DAYS, AND FAY COULD BE APPROACHING HURRICANE STRENGTH AS IT NEARS WESTERN
CUBA. TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 105 MILES, 165 KM FROM
THE CENTER. THE LATEST MINIMUM CENTRAL PRESSURE REPORTED BY THE HURRICANE
HUNTER IS 1006 MB, 29.71 INCHES.
TIDES OF 1 TO 3 FEET ABOVE NORMAL CAN BE EXPECTED IN THE WARNING AREA IN
AREAS OF ONSHORE FLOW. FAY IS EXPECTED TO PRODUCE TOTAL RAINFALL
ACCUMULATIONS OF 4 TO 8 INCHES OVER HISPANIOLA, EASTERN AND CENTRAL CUBA,
JAMAICA AND THE NORTHERN CAYMAN ISLANDS, WITH ISOLATED MAXIMUM AMOUNTS OF 15
INCHES. THESE RAINS COULD PRODUCE LIFE-THREATENING FLASH FLOODS AND MUD
SLIDES. RAINFALL ACCUMULATIONS OF 2 TO 4 INCHES ARE POSSIBLE OVER JAMAICA
AND THE NORTHERN CAYMAN ISLANDS, WHILE RAINFALL ACCUMULATIONS OF 1 TO 3
INCHES ARE POSSIBLE OVER THE SOUTHEASTERN BAHAMAS.
REPEATING THE 5:00 PM EDT POSITION, 19.3 N, 75.2 W. MOVEMENT TOWARD, WEST
NEAR 16 MPH. MAXIMUM SUSTAINED WINDS, 40 MPH. MINIMUM CENTRAL PRESSURE,
1006 MB. AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 8:00 PM EDT, FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 11:00 PM
EDT.
TROPICAL STORM FAY DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL062008
5:00 PM EDT SAT AUG 16 2008
REPORTS FROM AN AIR FORCE RESERVE HURRICANE HUNTER INDICATE THAT FAY IS A
LITTLE WEAKER THAN BELIEVED EARLIER, WITH THE INITIAL INTENSITY NEAR 35 KT
AND THE MINIMUM PRESSURE AT 1006 MB. THE SATELLITE APPEARANCE WAS RAGGED A
FEW HOURS AGO, BUT A NEW CLUSTER OF STRONG CONVECTION IS DEVELOPING IN THE
SOUTHEASTERN QUADRANT. THE CIRRUS OUTFLOW IS GOOD IN THE SOUTHEASTERN
SEMICIRCLE AND FAIR ELSEWHERE.
THE INITIAL MOTION IS 280/14. FAY REMAINS ON THE SOUTH SIDE OF A
LOW/MID-LEVEL RIDGE, WITH THE LARGE-SCALE MODELS FORECASTING A WEAKNESS IN
THE RIDGE OVER THE EASTERN GULF OF MEXICO OR FLORIDA THAT SHOULD ALLOW FAY
TO TURN TOWARD THE NORTH-NORTHWEST OR NORTH AFTER 36 HR. THERE IS A LARGE
SPREAD IN THE MODEL GUIDANCE ON WHEN AND HOW SHARPLY FAY WILL TURN. THE
ECMWF AND NAM MODELS REMAIN ON THE EASTERN SIDE OF THE GUIDANCE ENVELOPE,
AND HAVE BEEN JOINED BY THE GFDL WHICH HAS SHIFTED EASTWARD SINCE THE
PREVIOUS RUN. THESE MODELS CALL FOR A SOUTHEASTERN FLORIDA LANDFALL. THE
GFS...HWRF, GFDN, FLORIDA STATE SUPERENSEMBLE AND THE CONSENSUS MODELS
FORECAST FAY TO CROSS WEST CENTRAL CUBA AND MOVE NEAR OR OVER THE WEST COAST
OF THE FLORIDA PENINSULA. THE UKMET AND NOGAPS HAVE BOTH SHIFTED EAST OF
THEIR PREVIOUS RUNS, BUT ARE STILL ON THE WEST SIDE OF THE GUIDANCE ENVELOPE
IN CALLING FOR A MOTION TOWARD THE FLORIDA PANHANDLE. OVERALL, THE GUIDANCE
ENVELOPE AND THE MODEL CONSENSUS HAS CHANGED LITTLE SINCE THE LAST ADVISORY.
THE NEW FORECAST TRACK IS A LITTLE FASTER THAN THE PREVIOUS TRACK AND IS
SHIFTED A LITTLE TO THE EAST AFTER THE 48 HR POINT. EVERYONE IN THE FLORIDA
PENINSULA SHOULD MONITOR THE PROGRESS OF FAY, AS MOST LOCATIONS THERE HAVE
ABOUT THE SAME CHANCES OF EXPERIENCING HURRICANE-FORCE WINDS ACCORDING TO
THE NHC WIND SPEED PROBABILITY PRODUCT.
WHEN FAY IS OVER WATER, IT APPEARS THAT ATMOSPHERIC CONDITIONS WILL BE
FAVORABLE FOR STRENGTHENING THROUGH 72 HR. THUS, THE INTENSITY WILL BE
CONTROLLED BY LAND INTERACTION AND THE RESULTING IMPACTS ON THE STORM
STRUCTURE. ALL GUIDANCE CONTINUES TO FORECAST STRENGTHENING, AND THE
INTENSITY FORECAST FOLLOWS SUIT IN BEST AGREEMENT WITH THE SHIPS MODEL.
HOWEVER, THIS IS A LOW CONFIDENCE INTENSITY FORECAST. FAY COULD STRENGTHEN
RAPIDLY IF IT BECOMES WELL ORGANIZED OVER WATER...SUCH AS WHILE PASSING
SOUTH OF CUBA OR OVER THE STRAITS OF FLORIDA. ON THE OTHER HAND, IT MIGHT
NOT STRENGTHEN MUCH AT ALL IF LAND INTERACTION PREVENTS ORGANIZATION.
THE INTENSITY FORECAST CALLS FOR FAY TO WEAKEN OVER THE UNITED STATES AFTER
LANDFALL. SHOULD IT REMAIN OVER WATER AFTER 72 HR, THE LARGE-SCALE MODELS
FORECAST INCREASING WESTERLY VERTICAL SHEAR OVER THE SYSTEM.