WDPN31 PGTW 190300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 02W (TWO) WARNING 
NR 01//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL DEPRESSION (TD) 02W, LOCATED APPROXIMATELY 275 NM EAST 
SOUTHEAST OF ZAMBOANGA, PHILIPPINES, HAS TRACKED WESTWARD AT 11 
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE 
IMAGERY (MSI) DEPICTS WEAKLY FRAGMENTED BANDING WRAPPING INTO AN ILL-
DEFINED LOW LEVEL CIRCULATION CENTER. THE DISORGANIZATION IS ALSO 
APPARENT IN AN 182123Z SSMIS 91GHZ MICROWAVE IMAGE, HOWEVER AN 
EARLIER SCATTEROMETRY PASS DID REVEAL A 15-20 KNOT LLCC WITH 
STRONGER GRADIENT-INDUCED WINDS ON THE NORTHERN PERIPHERY. THE 
INITIAL POSITION IS BASED ON THE ANIMATED MSI AND THE PGTW FIX WITH 
POOR CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 25 KNOTS BASED 
ON THE PGTW DVORAK ESTIMATE AND TAKING INTO ACCOUNT THE GRADIENT 
WINDS. UPPER LEVEL ANALYSIS INDICATES TD 02W IS WELL SOUTH OF THE 
SUB-TROPICAL RIDGE AXIS IN AN AREA OF DIFFLUENCE, WHICH IS PROMOTING 
OUTFLOW. THE SYSTEM IS UNDER MODERATE (15-20 KNOTS) VERTICAL WIND 
SHEAR (VWS).
3. FORECAST REASONING.
   A. THIS IS THE INITIAL PROGNOSTIC REASONING AND SETS THE FORECAST 
PHILOSOPHY.
   B. THE SYSTEM IS CURRENTLY TRACKING SOUTHWESTWARD UNDER THE 
STEERING INFLUENCE OF THE MID-LEVEL SUB-TROPICAL RIDGE TO THE NORTH. 
AS THE SYSTEM MOVES PAST MINDINAO, LAND INTERACTION MAY FURTHER 
STIFLE THE LOW LEVEL ORGANIZATION. VWS IS EXPECTED TO REMAIN NEARLY 
CONSTANT THROUGH TAU 48, HOWEVER ONCE IN THE SULU SEA, THE FAVORABLE 
SST (28-29 DEGREES CELSIUS) AND FAIR OUTFLOW WILL ALLOW FOR MILD 
INTENSIFICATION INTO A MINIMAL TROPICAL STORM. AFTER TAU 48, TD 02W 
WILL BEGIN TO FEEL THE EFFECTS OF A NORTHEASTERLY SURGE. THE 
ADDITIONAL VWS AND WEAKER SSTS WILL RESULT IN GRADUAL WEAKENING.
   C. TD 02W IS FORECAST TO TRACK WESTWARD UNDER THE STEERING 
INFLUENCE OF THE MID-LEVEL SUB-TROPICAL RIDGE. ADDITIONAL VWS 
BROUGHT ON BY THE NORTHEASTERLY SURGE SHOULD CAUSE THE SYSTEM TO 
DISSIPATE BY TAU 96. THE AVAILABLE MODEL GUIDANCE IS IN FAIRLY GOOD 
AGREEMENT WITH THE TRACK AS THE SUB-TROPICAL RIDGING IS WELL IN 
PLACE, HOWEVER, OVERALL FORECAST CONFIDENCE IS LOW AT THIS TIME DUE 
TO THE CONFIDENCE OF THE INITIAL POSITION.//
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