KATE #11 - DISCUSSION

[AussieMark]

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WTNT41 KNHC 280900
TCDAT1
TROPICAL STORM KATE DISCUSSION NUMBER 11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT SUN SEP 28 2003

SATELLITE IMAGERY INDICATES THE LOW-LEVEL CENTER OF KATE IS NOW
TUCKED BENEATH THE DEEP CONVECTION. DVORAK CLASSIFICATIONS OF 3.5
AND 3.0 FROM TAFB AND SAB RESPECTIVELY FURTHER SUPPORT SOME LIMITED
DEEPENING OF THE SYSTEM. BASED ON THIS...THE INITIAL INTENSITY IS
INCREASED TO 50 KT.

LAST SEVERAL HOURS INDICATE THAT KATE IS NOW MOVING ALMOST DUE NORTH
AT 9 KT. GUIDANCE REMAINS SPLIT INTO TWO SCHOOLS...WITH THE
GFS...GFDL..AND UKMET INDICATING A TURN TO THE NORTHEAST AND EVEN
EAST-NORTHEAST BEYOND 72 HOURS AS THE SYSTEM GETS CAPTURED BY THE
MIDDLE TO UPPER LEVEL WESTERLIES. THE SECOND SCHOOL OF GUIDANCE
CONSISTS OF THE NOGAPS...GFDN...AND CANADIAN MODELS WHICH BOTH
BUILD A FAIRLY STRONG RIDGE TO THE NORTHEAST OF KATE BY DAY THREE
AND FORCE A TURN TO THE NORTHWEST AND WEST ON DAYS FOUR AND FIVE.
CONTINUING WITH EARLIER REASONING...THE OFFICIAL FORECAST CALLS FOR
RE CURVE SOUTH OF THE MID TO UPPER-LEVEL LOW NORTH OF THE CYCLONE
OVER THE FIRST 72 HOURS. BEYOND THAT TIME...THE OFFICIAL FORECAST
CALLS FOR A SLOWING IN THE FORWARD MOTION AND INDICATES A TURN TO
THE NORTHWEST AND WEST BY DAY FIVE.

SHIPS GUIDANCE INDICATES STRENGTHENING OF KATE TO MINIMAL HURRICANE
FORCE OVER THE FIRST 36 TO 48 HOURS WITH SLOW DECAY BEYOND THAT
TIME. ON THE OTHER HAND...GFDL CONTINUES TO DEEPEN THE SYSTEM TO 90
KT BY DAY THREE. GIVEN THAT KATE HAS DEEPENED IN A MODERATE SHEAR
ENVIRONMENT OVER THE LAST 24 HOURS...AND IS EXPECTED TO REMAIN IN A
SIMILAR ENVIRONMENT FOR THE NEXT 24 HOURS...THE OFFICIAL FORECAST
DOES CALL FOR SOME FURTHER STRENGTHENING INITIALLY WITH WEAKENING
THEREAFTER AS SHEAR BEGINS TO INCREASE FURTHER. THE FORECAST DOES
ALLOW FOR SOME RE INTENSIFICATION BY DAY FIVE SHOULD A COHERENT
WESTWARD MOVING TROPICAL CYCLONE STILL EXIST.

FORECASTER STEWART/HOLWEG

FORECAST POSITIONS AND MAX WINDS

INITIAL 28/0900Z 23.4N 44.5W 50 KT
12HR VT 28/1800Z 24.7N 44.3W 55 KT
24HR VT 29/0600Z 26.1N 43.4W 60 KT
36HR VT 29/1800Z 27.5N 42.1W 55 KT
48HR VT 30/0600Z 28.5N 40.6W 45 KT
72HR VT 01/0600Z 30.0N 38.5W 45 KT
96HR VT 02/0600Z 31.0N 38.5W 45 KT
120HR VT 03/0600Z 31.5N 39.0W 50 KT