WDPN33 PGTW 030300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 13W (NALGAE) 
WARNING NR 09//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL STORM (TS) 13W (NALGAE), LOCATED APPROXIMATELY 449 NM
NORTH-NORTHWEST OF WAKE ISLAND, HAS TRACKED WEST-NORTHWESTWARD AT 04
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS FLARING CENTRAL CONVECTION THAT IS SLIGHTLY
DISPLACED, PARTIALLY EXPOSING THE LOW LEVEL CIRCULATION (LLC). THE
INITIAL POSITION IS BASED ON THE PARTIALLY EXPOSED LLC IN THE MSI
LOOP WITH GOOD CONFIDENCE. THE INITIAL INTENSITY OF 35 KNOTS IS BASED
ON OBJECTIVE AND AGENCY DVORAK ESTIMATES AVERAGING T2.5. UPPER LEVEL
ANALYSIS INDICATES THE SYSTEM IS IN AN AREA OF LOW (10-15 KNOTS)
VERTICAL WIND SHEAR (VWS) AND STRONG EQUATORWARD OUTFLOW.
ADDITIONALLY, THE SYSTEM IS DRIFTING OVER WARM (27-28C) SSTS. THE
CYCLONE IS TRACKING SLOWLY ALONG THE SOUTHWEST PERIPHERY OF A LOW- TO
MID-LEVEL LAYER OF THE SUBTROPICAL RIDGE (STR) TO THE NORTHEAST.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST TRACK PHILOSOPHY SINCE THE PREVIOUS 
PROGNOSTIC REASONING MESSAGE.
   B. STEERED BY THE STR, TS 13W WILL CONTINUE ON ITS CURRENT TRACK
THROUGHOUT THE FORECAST PERIOD. AIDED BY A MARGINALLY FAVORABLE
ENVIRONMENT, THE SYSTEM WILL SEE MINIMAL INTENSIFICATION, REACHING 45
KNOTS BETWEEN TAU 24-48. AFTER TAU 48, INCREASING VWS AND COOLING
SSTS WILL GRADUALLY ERODE TS NALGAE. CONCURRENTLY, IT WILL BEGIN
EXTRA-TROPICAL TRANSITION, BECOMING A COLD-CORE LOW BY TAU 72.
DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT, LENDING HIGH CONFIDENCE 
TO THE JTWC TRACK FORECAST.//
NNNN