Tropical Storm GONI Advisory Pzt, 17.08.

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 16W (GONI) WARNING NR 12//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TYPHOON (TY) 16W (GONI), LOCATED APPROXIMATELY 175 NM WEST OF
ANATAHAN, HAS TRACKED WEST-NORTHWESTWARD AT 09 KNOTS OVER THE PAST
SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY DEPICTS A
RAPIDLY CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC) WITH A 10-
NM EYE. A 151719Z SSMI 85GHZ IMAGE SHOWS A SMALL EYEWALL WITH
TIGHTLY-CURVED SPIRAL BANDING WRAPPING INTO THE CENTER. THERE IS
GOOD CONFIDENCE IN THE CURRENT POSITION. ANIMATED WATER VAPOR
IMAGERY DEPICTS EXCELLENT OUTFLOW, ESPECIALLY POLEWARD OUTFLOW WHICH
IS ENHANCED BY THE TUTT POSITIONED TO THE NORTH. TY GONI IS
UNDERGOING RAPID INTENSIFICATION (RI), INCREASING 25 KNOTS OVER THE
PAST 24 HOURS FROM 55 KNOTS AT 15/18Z TO THE CURRENT INTENSITY OF 80
KNOTS. DVORAK INTENSITY ESTIMATES FROM ALL AGENCIES HAVE JUMPED TO
T4.5 (77 KNOTS). TY 16W CONTINUES TO TRACK ALONG THE SOUTHERN
PERIPHERY OF THE DEEP STR.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
   B. TY 16W WILL CONTINUE TO TRACK WEST-NORTHWESTWARD TO WESTWARD
THROUGH TAU 72 UNDER THE STEERING INFLUENCE OF THE STR. DUE TO THE
FAVORABLE ENVIRONMENTAL CONDITIONS, INCLUDING LOW VWS, WARM SST AND
EXCELLENT OUTFLOW, TY 16W IS FORECAST TO CONTINUE TO INTENSIFY
RAPIDLY THROUGH TAU 48 WITH A PEAK OF 130 KNOTS. MODEL GUIDANCE IS
IN TIGHT AGREEMENT AND SUPPORTS THE FORECAST TRACK WITH HIGH
CONFIDENCE.
   C. IN THE EXTENDED PERIOD, MODEL GUIDANCE FANS OUT WITH
INCREASING UNCERTAINTY IN BOTH TRACK SPEEDS AND THE TIMING OF THE
POLEWARD TURN. CURRENT NUMERICAL GUIDANCE INDICATES AN EXTREMELY
COMPLEX SYNOPTIC SITUATION AS A DEEP MIDLATITUDE SHORTWAVE TROUGH
DIGS INTO NORTHEASTERN CHINA, WEAKENING THE STR NORTH OF TY 16W.
ADDITIONALLY, TY 17W IS FORECAST TO TRACK NORTHWESTWARD SOUTH OF
HONSHU UNDER THE STEERING INFLUENCE OF THE STR TO ITS NORTH.
CONSEQUENTLY, TY 16W IS LIKELY TO BECOME EMBEDDED IN A WEAK STEERING
ENVIRONMENT AND EXHIBIT SLOW AND POSSIBLY EVEN QUASI-STATIONARY
MOTION NEAR TAIWAN. FURTHERMORE, THERE IS NO EVIDENCE THAT THE
TROUGH WILL BE DEEP ENOUGH TO INDUCE EXTRA-TROPICAL TRANSITION AS
THE BAROCLINIC ZONE REMAINS WELL NORTH OF 16W IN THE WEST SEA. FOR
THIS REASON, THERE IS HIGH OVERALL UNCERTAINTY IN THE JTWC FORECAST
TRACK.//
NNNN
NNNN