Tropical Storm MOLAVE Advisory Sat Oct 24

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 21W (TWENTYONE)
WARNING NR 001//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL DEPRESSION 21W (TWENTYONE), LOCATED APPROXIMATELY 335 NM
NORTHWEST OF KOROR, HAS TRACKED NORTHWESTWARD AT 16 KNOTS OVER THE
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
DEPICTS WELL DEFINED BANDING WRAPPING INTO A CONSOLIDATING LOW
LEVEL CIRCULATION CENTER. THE INITIAL POSITION WAS BASED ON THE PGTW
FIX WITH FAIR CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 30
KNOTS, WHICH IS SLIGHTLY HIGHER THAN SUBJECTIVE DVORAK FINAL-T
ESTIMATES FROM PGTW AND RJTD OF T1.5, BASED ON OVERALL STRUCTURE OF
THE BANDING. THE UPPER LEVEL ENVIRONMENT IS PROVIDING MODERATELY
FAVORABLE SUPPORT FOR DEVELOPMENT WITH IMPROVING EQUATORWARD OUTFLOW
AND LOW 5-10 KNOT VERTICAL WIND SHEAR (VWS). ADDITIONALLY, SEA
SURFACE TEMPERATURES OF 27-28 DEGREES CELSIUS ARE FAVORABLE. TD 21W
IS TRACKING GENERALLY NORTHWESTWARD UNDER A SUB-TROPICAL RIDGE TO
THE NORTH.
3. FORECAST REASONING.
   A. THIS IS THE INITIAL PROGNOSTIC REASONING AND SETS THE FORECAST
PHILOSOPHY.
   B. TD 21W IS EXPECTED TO CONTINUE CONSOLIDATING AS IT TRACKS
WESTWARD AS FAVORABLE CONDITIONS PERSIST, REACHING 60 KNOTS PRIOR TO
MAKING LANDFALL OVER THE EASTERN PHILIPPINES NEAR TAU 36. SLIGHT
WEAKENING IS EXPECTED AS THE SYSTEM TRANSITS OVER THE ARCHIPELAGO,
BEFORE RE-EMERGING IN THE SOUTH CHINA SEA WHERE RE-INTENSIFICATION
IS FORECAST TO REACH A PEAK OF 75 KNOTS AT TAU 72. NUMERICAL
GUIDANCE IS IN GOOD AGREEMENT THROUGH TAU 36, BUT BEGINS TO DIVERGE
AFTERWARDS AS SOME MODELS TRY TO WEAKEN THE STR. THE FORECAST IS
SLIGHTLY HIGHER THAN THE OFFICIAL CONSENSUS GIVEN CLIMATOLOGICALLY
FAVORABLE CONDITIONS. HOWEVER, THERE IS LIMITED GUIDANCE FOR THE
INITIAL FORECAST, LENDING LOW OVERALL CONFIDENCE.
   C. AFTER TAU 72, NUMERICAL GUIDANCE CONTINUES TO DIVERGE AS SOME
MEMBERS MORE AGGRESSIVELY WEAKEN THE STR. THE OFFICIAL FORECAST IS
PLACED CLOSE TO THE CONSENSUS MODEL BLEND, WHICH MAINTAINS THE STR,
WITH WESTWARD TO WEST NORTHWESTWARD MOTION. THE FORECAST INTENSITY
IS MAINTAINED GIVEN FAVORABLE CONDITIONS OVER THE SCS, UNTIL
LANDFALL OVER CENTRAL VIETNAM, WHICH OCCURS JUST PRIOR TO TAU 120.
GIVEN THE LIMITED FIRST WARNING GUIDANCE AND INCREASING MODEL
SPREAD, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE FORECAST.//
NNNN
NNNN