HOME	ARCHIVES	FORECASTS	IMAGERY	ABOUT TPC	RECONNAISSANCE

ZCZC MIATCDEP2 ALL
TTAA00 KNHC DDHHMM
TROPICAL STORM BORIS DISCUSSION NUMBER   7
NATIONAL WEATHER SERVICE MIAMI FL
8 PM PDT SUN JUN 09 2002

DURING THE PAST 6 HOURS...CONVECTION HAS BECOME ALMOST NON-EXISTENT 
NEAR THE PARTLY EXPOSED LOW-LEVEL CENTER. OUTFLOW IS GOOD IN THE 
WESTERN SEMICIRCLE...BUT IS RESTRICTED OR NON-EXISTENT TO THE EAST 
DUE TO STRONG UPPER-LEVEL EASTERLY SHEAR. THE INITIAL INTENSITY IS 
BASED ON A BLEND OF DVORAK SATELLITE INTENSITY ESTIMATES OF 35 TO 55 
KT FROM BOTH TAFB AND SAB...AND AN EARLIER REPORT FROM SHIP ELYL8 OF 
39 KT AND A 1003.8 MB PRESSURE ABOUT 70 NM NORTH OF THE CENTER.

THE INITIAL MOTION ESTIMATE IS 325/02. ALMOST ALL OF THE GLOBAL 
MODELS AND THE LATEST 18Z GFDL RUN DISSIPATE BORIS WITHIN 48 
HOURS...AND THEN KEEP THE CIRCULATION MILLING AROUND NEAR ITS 
CURRENT LOCATION. THE EXCEPTION IS THE AVN/GFS MODEL...WHICH DRIFTS 
BORIS NORTH-NORTHWESTWARD FOR 24 HOURS AND THEN TAKES THE REMNANT 
CIRCULATION SLOWLY WEST TO WEST-SOUTHWESTWARD AFTER THAT. GIVEN THE 
PERSISTENCE OF THE MODELS IN DISSIPATING BORIS OVER THE PAST FEW 
MODEL RUNS...THE OFFICIAL FORECAST TRACK IS CLOSE TO THE PREVIOUS 
TRACK THROUGH 36 HOURS...AND THEN CLOSER TO THE AVN/GFS SOLUTION 
AFTER THAT. HOWEVER...STEERING CURRENTS ARE FORECAST TO REMAIN WEAK 
THROUGHOUT THE PERIOD...SO BORIS COULD EASILY REMAIN STATIONARY.

LATEST SATELLITE IMAGERY INDICATES BORIS IS NOT LOOKING TOO 
HEALTHY...TO SAY THE LEAST. THE SHIPS INTENSITY MODEL HOLDS ON TO 
THE CYCLONE THROUGHOUT THE PERIOD AND ONLY DECREASES THE INTENSITY 
TO 40 KT IN 72 HOURS...IN SPITE OF SOME RATHER HOSTILE EAST TO 
SOUTHEASTERLY SHEAR OF 25 TO 35 KT. GIVEN THE AMOUNT OF VERTICAL 
SHEAR FORECAST BY THE AVN/GFS MODEL...COUPLED WITH THE DRY SUBSIDING 
AIR BEING ENTRAINED FROM MEXICO...I HAVE OPTED TO SLOWLY WEAKEN 
BORIS THROUGHOUT THE FORECAST PERIOD. THE 12 HOUR FORECAST INTENSITY 
MAY BE RATHER GENEROUS...BUT I DECIDED TO MAINTAIN THE INTENSITY OUT 
OF RESPECT FOR A POSSIBLE DIURNAL CONVECTIVE FLAREUP LATER TONIGHT.

THE 34-KT RADII WERE DECREASED SLIGHTLY AND THE 12-FT SEAS RADII 
WERE INCREASED BASED ON 21Z AND 00Z REPORTS FROM SHIP ELYL8.
 
FORECASTER STEWART
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL     10/0300Z 17.3N 104.3W    45 KTS
12HR VT     10/1200Z 17.7N 104.5W    45 KTS
24HR VT     11/0000Z 17.9N 104.8W    40 KTS
36HR VT     11/1200Z 18.2N 105.4W    35 KTS
48HR VT     12/0000Z 18.4N 106.0W    30 KTS
72HR VT     13/0000Z 18.0N 107.0W    25 KTS...DISSIPATING
 
 
NNNN