Tropical Storm KALMAEGI Advisory Paz, 14.09.

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 15W (KALMAEGI) WARNING NR 13//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 15W (KALMAEGI), LOCATED APPROXIMATELY 287 NM EAST-
NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED NORTHWESTWARD AT 11
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY INDICATES THAT THE SYSTEM HAS MAINTAINED CONVECTIVE
STRUCTURE WITH AN OBLONG CENTRAL DENSE OVERCAST FEATURE WITH DEEP
CONVECTIVE BANDING OVER THE SOUTHWEST QUADRANT. A 131714Z GCOMW1 89
GHZ IMAGE SHOWS AN ELONGATED MICROWAVE EYE FEATURE WITH INTENSE DEEP
CONVECTIVE BANDING WRAPPING INTO THE EASTERN QUADRANT OF THE LOW-
LEVEL CIRCULATION CENTER. BASED ON THE GCOMW1 IMAGE, THERE IS GOOD
CONFIDENCE IN THE INITIAL POSITION AND RECENT NORTHWESTWARD TRACK
MOTION. THE INITIAL INTENSITY REMAINS ASSESSED AT 65 KNOTS BASED ON
THE PERSISTENT CONVECTIVE STRUCTURE AND DVORAK INTENSITY ESTIMATES
OF T4.0 (65 KNOTS). DESPITE PERSISTENT MODERATE NORTHEASTERLY
VERTICAL WIND SHEAR (VWS), WHICH IS HINDERING DEEP CONVECTIVE
DEVELOPMENT OVER THE NORTHERN SEMI-CIRCLE, TY 15W APPEARS TO BE
FIGHTING THE ENVIRONMENT AND HAS SLIGHTLY IMPROVED POLEWARD OUTFLOW
OVER THE PAST 12 HOURS. ADDITIONALLY, THE MODERATE VWS IS BEING
REDUCED BY THE WESTWARD TRACK MOTION. RECENT 500 MB ANALYSES SHOW A
STRONG, BROAD, EAST-WEST ORIENTED SUBTROPICAL RIDGE (STR) ENTRENCHED
TO THE NORTH AND NORTHWEST.
 3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
   B. TY 15W IS FORECAST TO ACCELERATE WEST-NORTHWESTWARD UNDER THE
STEERING INFLUENCE OF THE STRONG STR THROUGH TAU 72. TY 15W IS
FORECAST TO INTENSIFY THROUGH TAU 12, PRIOR TO MAKING LANDFALL NEAR
TAU 18 OVER THE EASTERN COAST OF LUZON, UNDER FAVORABLE
ENVIRONMENTAL CONDITIONS TO INCLUDE WARM SST, HIGH OCEAN HEAT
CONTENT AND FAVORABLE OUTFLOW. AS TY 15W CROSSES THE MOUNTAINOUS
TERRAIN OF LUZON, IT IS FORECAST TO WEAKEN BUT IS EXPECTED TO RE-
INTENSIFY AFTER RE-EMERGING OVER THE SOUTH CHINA SEA.
   C. IN THE EXTENDED TAUS, TY 15W IS EXPECTED TO MAINTAIN A
PREDOMINANTLY WESTWARD TRACK THROUGH THE REMAINDER OF THE FORECAST
PERIOD AS THE STR REMAINS ENTRENCHED TO THE NORTH. NEAR TAU 72, TY
KALMAEGI IS FORECAST TO WEAKEN AS IT APPROACHES THE SOUTHERN COAST
OF CHINA AND SHOULD DISSIPATE BETWEEN TAU 96 AND 120 AS IT TRACKS
WELL INLAND. DYNAMIC MODEL GUIDANCE (INCLUDING THE MODEL ENSEMBLES)
IS IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE
JTWC FORECAST TRACK, WHICH IS POSITIONED CLOSE TO THE MULTI-MODEL
CONSENSUS.//
NNNN
NNNN