Tropical Storm BAILU Advisory 8月22日

MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 12W (BAILU)
WARNING NR 03//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   TROPICAL STORM (TS) 12W (BAILU), LOCATED APPROXIMATELY 736 NM
SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED NORTHWESTWARD AT 05 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE
IMAGERY SHOWS CONVECTION CONTINUES TO CONSOLIDATE AROUND THE LOW
LEVEL CIRCULATION CENTER (LLCC) WITH MOST OF THE DEEP CONVECTION
OFFSET TO THE SOUTHWEST. THE INITIAL POSITION IS PLACED WITH LOW
CONFIDENCE BASED ON EIR AND A 211716Z AMSR 37GHZ MICROWAVE IMAGE
WHICH SHOWS BANDING WRAPPING INTO THE LLCC. THE INTENSITY OF 35
KNOTS IS SET BETWEEN DVORAK CURRENT INTENSITY ESTIMATES OF T1.5-2.5
(25-42 KNOTS) AND IS SLIGHTLY ABOVE A 211810Z ADT ESTIMATE OF 33
KNOTS. ENVIRONMENTAL ANALYSIS SHOWS TS 12W IS EXPERIENCING FAVORABLE
VERTICAL WIND SHEAR (5 TO 15 KNOTS). TS 12W HAS A STRONG EQUATORWARD
OUTFLOW CHANNEL, HOWEVER, IT IS SLIGHTLY OFFSET SOUTHWESTWARD FROM
THE CURRENT POSITION. SEA SURFACE TEMPERATURES REMAIN FAVORABLE (28-
29 DEGREES CELSIUS) FOR DEVELOPMENT. TS 12W IS TRACKING
NORTHWESTWARD WHILE UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE (STR)
LOCATED TO THE NORTHEAST.
3. FORECAST REASONING.
   A. THERE IS NO CHANGE TO THE OVERALL FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. IN THE SHORT TERM, TS 12W WILL CONTINUE TO EXPERIENCE
FAVORABLE VERTICAL WIND SHEAR AND WILL REMAIN OVER WARM SEA SURFACE
TEMPERATURES. THESE CONDITIONS WILL ALLOW FOR A STEADY INCREASE IN
INTENSITY, REACHING 55 KNOTS BY TAU 48. THE STR TO THE NORTHEAST
WILL REMAIN IN PLACE THROUGH TAU 72 AND ALLOW TS 12W TO TRACK
NORTHWESTWARD. TS 12W WILL MAKE LANDFALL IN TAIWAN AROUND TAU 60.
PEAK WINDS MAY BE SLIGHTLY HIGHER (65-70 KNOTS) BETWEEN TAU 48 TO
TAU 72 BEFORE TS 12W MAKES LANDFALL IN TAIWAN. DYNAMIC MODEL
GUIDANCE IS IN GOOD AGREEMENT, WITH A SPREAD OF 115NM AT TAU 48,
HOWEVER, DUE TO THE UNCERTAINTY IN THE INITIAL POSITION THERE IS
MODERATE CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
   C. AFTER TAU 72, TS 12W WILL CONTINUE TO TRACK NORTHWESTWARD
WHILE UNDER THE INFLUENCE OF THE STR. BY TAU 72, TS 12W WILL EMERGE
INTO THE TAIWAN STRAIT AND THEN MAKE LANDFALL IN CENTRAL CHINA. LAND
INTERACTION WITH CHINA WILL CAUSE TS 12W TO QUICKLY WEAKEN AFTER
LANDFALL AND DISSIPATE BY TAU 120. DYNAMIC MODEL GUIDANCE IS IN POOR
AGREEMENT DURING THIS PORTION OF THE TRACK, WITH A SPREAD OF 890NM
BY TAU 120. DUE TO THE MODEL SPREAD AND THE HIGH UNCERTAINTY IN THE
INITIAL POSITION THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC
FORECAST TRACK.//
NNNN
NNNN