[Tropical] Tropical Cyclone Discussion

[EMWIN Server]

WTNT41 KNHC 140858
TCDAT1
TROPICAL DEPRESSION ELEVEN DISCUSSION NUMBER   3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5 AM EDT TUE SEP 14 2004

A RECENT WIND OBSERVATION FROM THE ISLAND OF DESIRADE WAS SSW/32
KTS. AND THE PRESSURE HAS GONE DOWN ANOTHER MILLIBAR TO 1009.  THE
SYSTEM IS NEARING TROPICAL STORM STATUS.  SATELLITE T NUMBERS ARE
T2.5 FROM TAFB AND T2.0 FROM SAB...AN AVERAGE OF ABOUT 32 KTS. THE
SYSTEM IS IN A LIGHT SHEAR REGIME AT THE MOMENT AND SHOULD DEVELOP
INTO A TROPICAL STORM SHORTLY.  HOWEVER...THERE ARE UPPER LEVEL
WESTERLIES JUST TO THE WEST OF THE SYSTEM THAT MAY PLAY A ROLE IN
THE FUTURE DEVELOPMENT.

THE SHIPS MODEL INDICATES THAT STRONG VERTICAL SHEAR OF 20-25 KTS
FROM THE NORTH...PART OF THE OUTFLOW FROM IVAN... WILL IMPACT THE
SYSTEM IN ABOUT 48 HOURS.  THE GFS 200 MILLIBAR WIND FIELD
ANIMATIONS SUPPORT THIS SCENARIO AND THE SYSTEM WILL PROBABLY
STRUGGLE AT THIS TIME.  HOWEVER...THE SHIPS FORECASTS THE SYSTEM TO
OVER COME THIS AND CONTINUE TO INTENSIFY.  THE SHIPS SOLUTION IS
FOLLOWED CLOSELY.

THE INITIAL MOTION IS 305/10. TD-11 IS MOVING ON THE SOUTH SIDE OF A
LARGE MID-ATLANTIC RIDGE. A PORTION OF THIS SAME RIDGE IS WEDGED
BETWEEN THE DEPRESSION AND HURRICANE IVAN AND IS FORECAST BY MOST
NUMERICAL GUIDANCE TO PERSIST THROUGHOUT THE FORECAST PERIOD. THIS
SCENARIO SHOULD CAUSE THE SYSTEM TO SLOW DOWN AFTER ABOUT 36 TO 48
HOURS AND THEN TURN TOWARD THE NW AS THE RIDGE IS WEAKENED BY IVAN.

FORECASTER JARVINEN

FORECAST POSITIONS AND MAX WINDS

INITIAL      14/0900Z 16.6N  62.2W    30 KT
 12HR VT     14/1800Z 17.4N  63.6W    35 KT
 24HR VT     15/0600Z 18.5N  65.3W    45 KT
 36HR VT     15/1800Z 19.5N  67.1W    50 KT
 48HR VT     16/0600Z 20.4N  68.8W    55 KT
 72HR VT     17/0600Z 21.6N  70.7W    60 KT
 96HR VT     18/0600Z 23.0N  72.0W    65 KT
120HR VT     19/0600Z 25.0N  73.4W    70 KT


$$
This weather bulletin was brought to you by:
www.nashvilleweather.net