MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 28W (TRAMI) WARNING NR 33//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON (TY) 28W (TRAMI), LOCATED APPROXIMATELY 126 NM SOUTH-
SOUTHWEST OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED NORTH-
NORTHWESTWARD AT 08 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED
INFRARED SATELLITE IMAGERY SHOWS THE SYSTEM HAS BECOME MORE EXPANSIVE
AND HAS MAINTAINED A VERY LARGE 84-NM RAGGED EYE. THE INITIAL
POSITION IS BASED ON THE EYE FEATURE AND ON NEARLY-CONCENTRIC 281800Z
AGENCY AND RADAR POSITION FIXES WITH HIGH CONFIDENCE. THE INITIAL
INTENSITY OF 90 KNOTS IS BASED ON EQUIVALENT DVORAK ESTIMATES OF
T5.0/90 KNOTS FROM PGTW RJTD. ENVIRONMENTAL ANALYSIS INDICATES THAT
TY 28W IS STILL IN LOW (5 TO 10 KNOT) VERTICAL WIND SHEAR (VWS) AND
EXCELLENT RADIAL OUTFLOW. SEA SURFACE TEMPERATURES ALSO REMAIN
FAVORABLE AT 28 TO 29 CELSIUS. THE CYCLONE IS TRACKING ALONG THE
WESTERN EDGE
OF THE SUBTROPICAL RIDGE (STR) TO THE EAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TY TRAMI WILL CREST THE STR AXIS OVER THE NEXT FEW HOURS AND
BEGIN TO ACCELERATE NORTHEASTWARD, MAKING LANDFALL ALONG THE EAST
COAST OF SHIKOKU, JAPAN, NEAR TAU 36. THE SYSTEM WILL QUICKLY DRAG
ACROSS HONSHU AND BY TAU 72, WILL HAVE MADE IT TO JUST SOUTH
KAMCHATKA PENINSULA. INITIAL EXPOSURE TO THE STRONG WESTERLIES
ASSOCIATED WITH AN APPROACHING MID-LATITUDE TROUGH, IN ADDITION TO
THE AFOREMENTIONED FAVORABLE CONDITIONS, WILL FUEL SLIGHT
INTENSIFICATION TO 100 KNOTS BY TAU 24. AFTERWARD, INCREASING VWS
ALONG WITH INTERACTION WITH THE JAPANESE ISLANDS WILL LEAD TO GRADUAL
DECAY. CONCURRENTLY, THE SYSTEM WILL BEGIN EXTRA-TROPICAL TRANSITION
AROUND TAU 36 AND BY TAU 48, WILL BECOME A COLD CORE LOW WITH AN
EXPANDING WIND FIELD. DYNAMIC MODEL GUIDANCE IS IN VERY TIGHT
AGREEMENT; THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST
TRACK.//
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