93W TCFA - 颱風討論

http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/warnings/wp9317web.txt
http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/warnings/wp9317.gif

WTPN22 PGTW 182030
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 250 NM RADIUS OF 15.3N 149.2E WITHIN THE NEXT 12 TO 24 HOURS.
AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF NUMBERED TROPICAL
CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA ARE ESTIMATED TO
BE 15 TO 20 KNOTS. METSAT IMAGERY AT 181800Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 15.5N 147.8E. THE SYSTEM IS
MOVING EASTWARD AT 10 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 93W) PREVIOUSLY LOCATED
NEAR 15.1N 145.6E, IS NOW LOCATED NEAR 15.5N 147.8E, APPROXIMATELY
670 NM SOUTHEAST OF IWO TO. ANIMATED INFRARED SATELLITE IMAGERY
DEPICTS PERSISTENT CONVECTION LOCATED DIRECTLY OVER A BROAD LOW-
LEVEL CIRCULATION CENTER (LLCC). AN 181536Z 89GHZ AMSR-2 MICROWAVE
IMAGE INDICATES DISTINCT BANDING WRAPPING IN FROM THE SOUTH, WITH
DEEP CONVECTION LOCATED IN THE NORTHEAST QUADRANT. UPPER-LEVEL
ANALYSIS REVEALS A MARGINALLY FAVORABLE ENVIRONMENT WITH MODERATE
VERTICAL WIND SHEAR (15-20 KT), WITH HIGH VERTICAL WIND SHEAR TO THE
NORTH AND SOUTH. GOOD DIFFLUENCE ALOFT IS FUELING DEEP CONVECTION.
SSTS ARE FAVORABLE, IN THE 30-31C RANGE. GLOBAL MODEL TRACK AND
INTENSITY GUIDANCE DIFFERS GREATLY OVER THE NEXT SEVERAL DAYS. SOME
MODELS PREDICT AN EASTWARD TRACK, TURNING NORTHWARD THEN RECURVING,
WITH GRADUAL INTENSIFICATION. OTHERS PREDICT SOUTHEASTWARD MOTION
AND LITTLE TO NO CONSOLIDATION. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1007 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
192030Z.//
NNNN

繼蘭恩西側擾動升格成26W之後，東側的擾動也發出了TCFA，
老J認為雖然垂直風切不友善，
但整體高空環境加上超過30度的海表面溫度仍支持進一步發展。

儘管老J認為26W能加強到至少熱帶風暴強度，不過EC對26W和93W的反應都很微弱。

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