TCPAT4
BULLETIN
HURRICANE DEAN ADVISORY NUMBER 32
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
1100 PM EDT MON AUG 20 2007

...EYE OF POTENTIALLY CATASTROPHIC HURRICANE DEAN JUST A FEW HOURS
FROM LANDFALL ALONG THE EAST COAST OF THE YUCATAN PENINSULA...

AT 11 PM EDT...0300 UTC...THE GOVERNMENT OF MEXICO HAS EXTENDED THE
HURRICANE WARNING WESTWARD FROM CIUDAD DE CARMEN TO CHILITEPEC. A
HURRICANE WARNING IS NOW IN EFFECT FOR THE ENTIRE COASTLINE OF
BELIZE...ALONG THE EAST COAST OF THE YUCATAN PENINSULA OF MEXICO
FROM THE BELIZE/MEXICO BORDER NORTHWARD TO CANCUN...AND ALONG THE
WEST COAST OF THE YUCATAN PENINSULA FROM SOUTH OF PROGRESSO
SOUTHWARD TO CHILITEPEC. PREPARATIONS TO PROTECT LIFE AND PROPERTY
ALONG THE EAST COAST OF THE YUCATAN PENINSULA SHOULD HAVE ALREADY
BEEN COMPLETED. PREPARATIONS ELSEWHERE IN THE HURRICANE WARNING
AREA SHOULD BE RUSHED TO COMPLETION.

AT 11 PM EDT...THE GOVERNMENT OF MEXICO HAS ISSUED A TROPICAL STORM
WARNING AND A HURRICANE WATCH FROM WEST OF CHILITEPEC WESTWARD TO
VERACRUZ MEXICO...AND A HURRICANE WATCH HAS ALSO BEEN ISSUED FROM
VERACRUZ TO TAMPICO. A HURRICANE WATCH MEANS THAT HURRICANE
CONDITIONS ARE POSSIBLE WITHIN THE WATCH AREA...GENERALLY WITHIN 36
HOURS. A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM
CONDITIONS ARE EXPECTED WITHIN THE WARNING AREA WITHIN THE NEXT 24
HOURS.

A TROPICAL STORM WARNING IS ALSO IN EFFECT ALONG THE NORTHERN COAST
OF THE YUCATAN PENINSULA FROM NORTH OF CANCUN TO PROGRESSO.

A TROPICAL STORM WATCH ALSO REMAINS IN EFFECT FOR THE FOLLOWING
PROVINCES OF CUBA...PINAR DEL RIO...LA HABANA...AND ISLA DE LA
JUVENTUD.

INTERESTS ELSEWHERE IN THE SOUTHERN GULF OF MEXICO SHOULD CLOSELY
MONITOR THE PROGRESS OF DEAN.

FOR STORM INFORMATION SPECIFIC TO YOUR AREA...INCLUDING POSSIBLE
INLAND WATCHES AND WARNINGS...PLEASE MONITOR PRODUCTS ISSUED
BY YOUR LOCAL WEATHER OFFICE.

AT 1100 PM EDT...0300Z...THE CENTER OF HURRICANE DEAN WAS LOCATED
NEAR LATITUDE 18.4 NORTH...LONGITUDE 86.0 WEST OR ABOUT 150 MILES...
245 KM...EAST OF CHETUMAL MEXICO AND ABOUT 310 MILES...500 KM...
EAST-SOUTHEAST OF CAMPECHE MEXICO.

DEAN IS MOVING TOWARD THE WEST NEAR 20 MPH...32 KM/HR...AND THIS
MOTION IS EXPECTED TO CONTINUE TONIGHT AND TUESDAY. ON THE FORECAST
TRACK...THE EYE OF DEAN WILL MAKE LANDFALL ALONG THE EAST COAST OF
THE YUCATAN PENINSULA VERY EARLY TUESDAY MORNING. DEAN WILL CROSS
THE YUCATAN PENINSULA DURING THE DAY ON TUESDAY AND LIKELY REACH
THE BAY OF CAMPECHE TUESDAY NIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 160 MPH...260 KM/HR...WITH HIGHER
GUSTS. DEAN IS A POTENTIALLY CATASTROPHIC CATEGORY FIVE HURRICANE
ON THE SAFFIR-SIMPSON HURRICANE SCALE. LITTLE CHANGE IN STRENGTH
IS EXPECTED PRIOR TO LANDFALL ON THE EAST COAST OF THE YUCATAN
PENINSULA. ALTHOUGH SOME WEAKENING IS FORECAST AS DEAN CROSSES THE
YUCATAN PENINSULA...DEAN IS EXPECTED TO MAINTAIN HURRICANE STRENGTH
THROUGHOUT THE NEXT 24 HOURS.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 60 MILES...95 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 175
MILES...280 KM.

THE MOST RECENT MINIMUM CENTRAL PRESSURE MEASURED BY AN AIR FORCE
RESERVE RECONNAISSANCE AIRCRAFT WAS 914 MB...26.99 INCHES.

DEAN IS EXPECTED TO PRODUCE STORM TOTAL RAINFALL OF 5 TO 10 INCHES
OVER THE ISTHMUS OF TEHUANTEPEC AND YUCATAN PENINSULA OF
MEXICO...BELIZE...GUATEMALA...AND NORTHERN HONDURAS...WITH MAXIMUM
AMOUNTS OF UP TO 20 INCHES. THESE RAINS COULD CAUSE
LIFE-THREATENING FLASH FLOODS AND MUD SLIDES.

STORM SURGE FLOODING OF 12 TO 18 FEET ABOVE NORMAL TIDE LEVELS IS
POSSIBLE NEAR AND TO THE NORTH OF WHERE DEAN MAKES LANDFALL ALONG
THE EAST COAST OF THE YUCATAN PENINSULA.

REPEATING THE 1100 PM EDT POSITION...18.4 N...86.0 W. MOVEMENT
TOWARD...WEST NEAR 20 MPH. MAXIMUM SUSTAINED WINDS...160 MPH.
MINIMUM CENTRAL PRESSURE...914 MB.

AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE
CENTER AT 200 AM EDT FOLLOWED BY THE NEXT COMPLETE ADVISORY AT 500
AM EDT.


FORECASTER KNABB/ROBERTS



TCDAT4
HURRICANE DEAN DISCUSSION NUMBER 32
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042007
1100 PM EDT MON AUG 20 2007

DEAN HAS TAPPED INTO ENERGY PROVIDED BY THE DEEP WARM WATERS OF THE
NORTHWESTERN CARIBBEAN SEA THIS EVENING...AND HAS REACHED CATEGORY
FIVE STATUS WITH AN INTENSITY OF 140 KT. DURING THE LAST
PENETRATION BY THE AIR FORCE RESERVE UNIT RECONNAISSANCE AIRCRAFT
AT 00Z...A CENTRAL PRESSURE OF 914 MB WAS MEASURED. THE PEAK
FLIGHT-LEVEL WIND WAS 162 KT...WHICH CORRESPONDS TO ABOUT 145 KT AT
THE SURFACE. DUE TO COMMUNICATIONS PROBLEMS...WE HAVE NOT RECEIVED
ALL OF THE DROPSONDE AND SFMR DATA IN REAL-TIME. THE ADVISORY
INTENSITY IS SET TO A POSSIBLY CONSERVATIVE 140 KT...PENDING A MORE
THOROUGH EXAMINATION OF ALL OF THE AIRCRAFT DATA. ANOTHER AIRCRAFT
WILL ARRIVE IN THE EYE OF DEAN IN A FEW HOURS...PRIOR TO LANDFALL
ALONG THE EAST COAST OF THE YUCATAN PENINSULA. THE EVOLVING
SATELLITE PRESENTATION OF DEAN REVEALS AN INCREASINGLY SYMMETRIC
CONVECTIVE PATTERN...AND A VERY WELL-DEFINED AND GRADUALLY
CONTRACTING EYE WITH A DIAMETER OF ABOUT 20 N MI. REPORTS FROM THE
AIRCRAFT...AND RECENT MICROWAVE SATELLITE IMAGERY...PROVIDE NO
INDICATIONS OF ANY INNER-CORE STRUCTURAL CHANGES THAT WOULD LEAD TO
WEAKENING PRIOR TO LANDFALL. THE OFFICIAL INTENSITY FORECAST IS
ESSENTIALLY UNCHANGED. DEAN IS EXPECTED TO MAINTAIN HURRICANE
STATUS DURING ITS ENTIRE STAY OVER YUCATAN...AND IT COULD STILL
REGAIN MAJOR HURRICANE STATUS OVER THE BAY OF CAMPECHE BEFORE FINAL
LANDFALL IN ABOUT 36 HOURS.

THE HURRICANE GENERALLY REMAINS ON TRACK WITH AN INITIAL MOTION OF
275/17. A STRENGTHENING RIDGE OVER THE SOUTHEASTERN UNITED STATES
SHOULD CONTINUE TO PUSH DEAN ROUGHLY ALONG THIS SAME HEADING AND
SPEED FOR THE NEXT COUPLE OF DAYS UNTIL DISSIPATION OVER MAINLAND
MEXICO. THE NEW OFFICIAL FORECAST IS AGAIN ADJUSTED TO THE SOUTH
IN ORDER TO MAINTAIN THE CURRENT WELL-ESTABLISHED HEADING...AND TO
BE IN BETTER AGREEMENT WITH A CONSENSUS OF THE GFDL...GFS...AND
NOGAPS MODELS. ALONG THE NEW TRACK...DEAN WILL SPEND A LITTLE LESS
TIME OVER THE BAY OF CAMPECHE...AND WILL PASS A LITTLE CLOSER TO
THE NORTHERN COAST OF THE ISTHMUS OF TEHUANTEPEC DURING THE 24-36
HOUR PERIOD. AS A RESULT...NEW WATCHES AND WARNINGS HAVE BEEN
ISSUED ALONG THE COAST OF MAINLAND MEXICO.


FORECAST POSITIONS AND MAX WINDS

INITIAL 21/0300Z 18.4N 86.0W 140 KT
12HR VT 21/1200Z 18.7N 88.6W 140 KT...INLAND OVER YUCATAN
24HR VT 22/0000Z 19.2N 92.1W 85 KT...BAY OF CAMPECHE
36HR VT 22/1200Z 19.6N 95.6W 95 KT...BAY OF CAMPECHE
48HR VT 23/0000Z 19.6N 99.1W 30 KT...INLAND OVER MEXICO
72HR VT 24/0000Z...DISSIPATED


FORECASTER KNABB/ROBERTS