Tropical Storm TWELVE Advisory Sat Jul 25

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 12W (TWELVE)
WARNING NR 08//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL DEPRESSION (TD) 12W (TWELVE), LOCATED APPROXIMATELY 355
NM NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED EAST-NORTHEASTWARD
AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY DEPICTS A WEAK, FULLY-EXPOSED LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH FLARING, DISORGANIZED DEEP CONVECTION
DISPLACED OVER THE WESTERN SEMI-CIRCLE DUE TO MODERATE TO STRONG (20
TO 30 KNOTS) NORTHEASTERLY VERTICAL WIND SHEAR (VWS). A 242231Z
SSMIS 37 GHZ IMAGE REFLECTS THE GENERAL WEAKENING TREND AND SHALLOW
BANDING WRAPPING BROADLY INTO THE CENTER. A 250038Z ASCAT PARTIAL
IMAGE OVER THE EASTERN SEMI-CIRCLE ALSO SUPPORTS THE WEAKENING
CIRCULATION WITH ONLY 10 TO 15 KNOT SOUTHERLY WINDS. ANIMATED WATER
VAPOR IMAGERY SHOWS THE OUTFLOW BANDS FROM TY 01C APPROACHING TS 12W
FROM THE NORTHEAST, BEGINNING THEIR INTERACTION. UPPER LEVEL
ANALYSIS INDICATES A MARGINAL ENVIRONMENT WITH MODERATE VERTICAL
WIND SHEAR (VWS) AND WEAK EQUATORWARD OUTFLOW. THE CURRENT
INTENSITY IS ASSESSED AT 30 KNOTS BASED ON THE CONVECTIVE SIGNATURE
AND DVORAK INTENSITY ESTIMATES OF 25 KNOTS. TD 12W IS TRACKING ALONG
THE WESTERN PERIPHERY OF THE LOW- TO MID-LEVEL STR TO THE EAST.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
   B. TD 12W IS CURRENTLY LOCATED ABOUT 525 NM FROM TY 01C, WHICH
HAS LED TO WEAK DIRECT CYCLONE INTERACTION; HOWEVER, AS TY 01C TURNS
POLEWARD THIS IS EXPECTED TO DECREASE. THEREAFTER, TD 12W WILL
ACCELERATE POLEWARD. MARGINAL ENVIRONMENTAL CONDITIONS WILL PROHIBIT
SIGNIFICANT DEVELOPMENT OF THE CYCLONE AS IT GAINS LATITUDE. IN
ADDITION, INCREASED VWS AND SUBSIDENCE CAUSED BY THE INTERACTION
WITH TY 01C WILL FURTHER DETERIORATE THE UPPER-LEVEL ENVIRONMENT. TD
12W WILL CONTINUE TO WEAKEN DUE TO THE POOR ENVIRONMENTAL FACTORS,
LEADING TO ITS DISSIPATION BY THE END OF THE FORECAST PERIOD.
DYNAMIC MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A HIGH DEGREE OF
UNCERTAINTY DUE TO TY 01C PASSING TO THE NORTH. DUE TO THE CONTINUED
MODEL SPREAD, THERE IS LOW CONFIDENCE IN THE JTWC FORECAST.//
NNNN
NNNN