000
WTPZ44 KNHC 102038
TCDEP4
TROPICAL DEPRESSION NINE-E DISCUSSION NUMBER   5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   EP092009
200 PM PDT MON AUG 10 2009
 
VERTICAL WIND SHEAR...ANALYZED AT 18 KT BY THE SHIPS MODEL...HAS
TAKEN A TOLL ON THE DEPRESSION...LEAVING THE LOW-LEVEL CENTER
EXPOSED FOR A TIME TO THE WEST OF BURSTING DEEP CONVECTION. THE
INITIAL INTENSITY IS HELD AT 30 KT FOR THIS ADVISORY...AND LITTLE
CHANGE IS FORECAST OVER THE NEXT COUPLE OF DAYS...IN GOOD AGREEMENT
WITH MOST OF THE INTENSITY GUIDANCE. ONLY THE SHIPS MODEL SHOWS ANY
APPRECIABLE INTENSIFICATION AS IT PREDICTS THAT THE VERTICAL SHEAR
OVER THE CYCLONE WILL DECREASE TEMPORARILY BETWEEN 36 AND 72 HOURS.
MOST OF THE OTHER GUIDANCE SHOWS FURTHER WEAKENING OR DISSIPATION
AT 72 HOURS AND BEYOND. THE OFFICIAL FORECAST IS FOR THE CYCLONE TO
BECOME A REMNANT LOW BY DAY 4 AND DISSIPATE BY DAY 5...BUT THIS
COULD OCCUR EVEN EARLIER.
 
THE DEPRESSION APPEARS TO BE MOVING SOUTH OF WEST FOR THE LAST
COUPLE OF HOURS...BUT THE LONGER-TERM MOTION IS ESTIMATED AT
275/10. THE FORECAST TRACK HAS BEEN ADJUSTED TO THE SOUTH OF THE
PREVIOUS PACKAGE AND IS SOUTH OF THE MODEL CONSENSUS. GIVEN THE
INCREASINGLY SHALLOW NATURE OF THE SYSTEM...THERE IS LITTLE REASON
FOR THE SYSTEM TO GAIN MUCH LATITUDE AS IT IS STEERED BY THE
LOW-LEVEL EASTERLY FLOW. MUCH OF THE GUIDANCE SUGGESTS A SOUTHWARD
COMPONENT OF MOTION DEVELOPING LATE IN THE PERIOD...IF THE CYCLONE
SURVIVES THAT LONG. THE FORWARD SPEED IS CLOSE TO THAT OF THE
MULTI-MODEL CONSENSUS TVCN.
 
FORECAST POSITIONS AND MAX WINDS
 
INITIAL      10/2100Z 15.1N 124.2W    30 KT
 12HR VT     11/0600Z 15.2N 125.6W    30 KT
 24HR VT     11/1800Z 15.4N 127.4W    30 KT
 36HR VT     12/0600Z 15.6N 129.3W    30 KT
 48HR VT     12/1800Z 15.6N 131.3W    25 KT
 72HR VT     13/1800Z 15.5N 135.5W    25 KT
 96HR VT     14/1800Z 15.5N 139.5W    20 KT...REMNANT LOW
120HR VT     15/1800Z...DISSIPATED
 
$$
FORECASTER BRENNAN