91W TCFA GW - 颱風討論

http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/warnings/wp9115.gif
http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/warnings/wp9115web.txt

WTPN21 PGTW 200300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 14.9N 111.8E TO 18.5N 110.8E
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 18 TO 23 KNOTS. METSAT
IMAGERY AT 200000Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.6N 111.6E. THE SYSTEM IS MOVING NORTH-NORTHWESTWARD AT 05
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.1N
112.9E, IS NOW LOCATED NEAR 15.6N 111.6E, APPROXIMATELY 235 NM EAST-
SOUTHEAST OF HUE, VIETNAM. ANIMATED MSI DEPICTS IMPROVING CONVECTIVE
BANDING, ESPECIALLY ON THE WESTERN AND SOUTHERN PERIPHERY OF AN
ELONGATED LLCC. A 202257Z WINDSAT IMAGES SHOWS THAT THE MAJORITY OF
WINDS NOT LOCATED IN THE DEEP CONVECTION ARE BETWEEN 15 AND 20
KNOTS. UPPER-LEVEL ANALYSIS INDICATES SOME DIVERGENCE ALOFT OFF-
SETTING THE 10 TO 20 KNOTS OF VWS. MODEL DEVELOPMENT FOR THIS SYSTEM
IS MARGINAL, DEVELOPING THIS SYSTEM AS AN EFFECT OF THE SURGE EVENT
OCCURRING IN THE SOUTHERN PORTION OF THE SOUTH CHINA SEA.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. BASED ON
IMPROVED STRUCTURE AND FAVORABLE CONDITIONS, 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
210300Z.//
NNNN

定位似乎往西調整

明顯季風低壓的外強中乾特徵，但與多數季風低壓相比較無多中心的問題

數值後期因副高西伸而跑出路徑未來西北折。

對台無直接影響，做為2015年颱風旺季開端的象徵意義較大，

但環流龐大仍可能造成西半部和外島天氣不穩定。

http://www.jma.go.jp/jp/typh/a.html

熱帯低気圧
平成27年06月20日16時15分 発表

<20日15時の実況>
大きさ -
強さ -
熱帯低気圧
存在地域 南シナ海
中心位置 北緯 15度20分(15.3度)
東経 111度50分(111.8度)
進行方向、速さ 北北西 ゆっくり
中心気圧 1002hPa
中心付近の最大風速 15m/s(30kt)
最大瞬間風速 23m/s(45kt)

<21日15時の予報>
強さ -
存在地域 南シナ海
予報円の中心 北緯 17度25分(17.4度)
東経 111度50分(111.8度)
進行方向、速さ 北 ゆっくり
中心気圧 1000hPa
中心付近の最大風速 18m/s(35kt)
最大瞬間風速 25m/s(50kt)
予報円の半径 220km(120NM)

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