Tropical Storm HAIMA Advisory Wed Oct 19

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 25W (HAIMA) WARNING NR
18//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   SUPER TYPHOON 25W (HAIMA), LOCATED APPROXIMATELY 301 NM EAST-
NORTHEAST OF MANILA, PHILIPPINES, HAS TRACKED WESTWARD AT 14
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A HIGHLY SYMMETRIC AND TIGHTLY WOUND SPIRAL SYSTEM
WITH A WELL-DEFINED 25 NM EYE, GIVING HIGH CONFIDENCE TO THE INITIAL
POSITION. THE INITIAL INTENSITY OF 140 KNOTS IS BASED ON THE LOWER
END OF CURRENT INTENSITY DVORAK ESTIMATES RANGING FROM T7.0 TO T7.5
(140 TO 155 KNOTS), GIVEN THAT RJTD AND PGTW HAVE BOTH DROPPED THEIR
FINAL T VALUES BY 0.5 IN THE LAST SIX HOURS. UPPER-LEVEL ANALYSIS
SHOWS EXCELLENT RADIAL OUTFLOW DIRECTLY OVER THE SYSTEM AND LOW
VERTICAL WIND SHEAR. THERE IS A PROMINENT ANTICYCLONE FEATURE TO THE
NORTH BLOCKING THE NORMALLY ESTABLISHED POLEWARD OUTFLOW CHANNEL,
BUT GIVEN THE IMPRESSIVE CURRENT INTENSITY THE RESTRICTION TO FLOW
IS HAVING LIMITED IMPACT. SEA SURFACE TEMPERATURES ARE VERY
FAVORABLE NEAR 29 TO 30 CELSIUS. CURRENTLY STY HAIMA IS TRACKING
WESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL
RIDGE TO THE NORTH.
3. FORECAST REASONING.
   A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING BULLETIN.
   B. STY HAIMA WILL CONTINUE TO TRACK WESTWARD GUIDED BY THE
CURRENT STEERING RIDGE. THE INTENSITY IS EXPECTED TO MAINTAIN AT
SUPER TYPHOON STRENGTH FOR THE NEXT 12 HOURS UNTIL THE SYSTEM BEGINS
TO INTERACT WITH LUZON AND BEGIN TO WEAKEN. BY TAU 24 STY HAIMA WILL
REEMERGE OVER WATER REORGANIZING AS A TYPHOON AND CONTINUE
NORTHWESTWARD UNDER STILL FAVORABLE CONDITIONS. THE SYSTEM IS
EXPECTED TO MAKE LANDFALL AGAIN JUST EAST OF HONG KONG AROUND TAU 60
AND SIGNIFICANTLY WEAKEN AS IT TRACKS INLAND AND STARTS TO TURN
NORTHWEST ROUNDING THE RIDGE AXIS.
   C. IN THE EXTENDED TAUS, STY HAIMA WILL ROUND THE RIDGE AXIS AND
SHIFT TO A NORTHEASTERN TRACK. THE SYSTEM WILL REMAIN FOR AN
EXTENSIVE PERIOD OVER LAND AND WEAKEN SIGNIFICANTLY.  BY TAU 120 THE
REMNANTS OF STY HAIMA WILL REEMERGE OVER WATER COMPLETELY
DISSIPATED. DYNAMIC MODEL GUIDANCE IS IN VERY GOOD AGREEMENT AS THE
SYSTEM TRACKS WEST THROUGH TAU 72 AND MAKES LANDFALL NEAR HONG KONG.
HOWEVER, BEYOND TAU 72 THERE IS SOME SPREAD IN THE TRACK AS THE
SYSTEM ROUNDS THE RIDGE AXIS WITH A LARGE DEGREE OF VARIABILITY
WHERE THE REMNANTS OF THE SYSTEM WILL EMERGE OVER WATER. OVERALL
THERE IS HIGH CONFIDENCE IN THE FORECAST TRACK.//
NNNN
NNNN