正宜27

  基本資料  
編號　　　　：99 W
擾動編號日期：2020 年 07 月 11 日 13 時
撤編日期　　：2020 年 07 月 15 日 20 時
99W.INVEST.15kts-18.0N-131.0E

ben811018

９９Ｗ位於太平洋高氣壓南側，
屬於東風波下的產物，
持續朝西移動，
下週二左右抵達台灣東方海域。

由於太平洋高氣壓強盛，
且前方的垂直風切偏強、較為乾燥，
環境不適合９９Ｗ更進一步增強，

因此到台灣附近時，
頂多維持現有強度或熱帶低壓，
成為颱風機會不高。

當然，還有２天給他表現，
看會不會有意外發展囉ＸＤ

至於對天氣的影響，
還是得看他之後怎麼發展，
繼續觀察囉！

老農民版夜神月

JMA12Z升格為TD

TROPICAL DEPRESSION 1008 HPA AT 18N 130E WNW SLOWLY.

副熱帶高壓脊

老農民版夜神月 發表於 2020-7-11 22:38
JMA12Z升格為TD

一開始感覺上JMA是過早升格，畢竟西太自鸚鵡之後也沒擾動了，但看了風場照到25knots，就不早了，17年洛克也是在HKO「擾動」時照到35knots的，等到HKO升TS，JMA也降TD了風埸也再沒掃到35knots了。
的確，有風埸支持下，JMA的升格正確，菲東潛熱多，還看時間

jrchang5

JTWC 11/22Z評級Low。

(1) AN AREA OF CONVECTION (INVEST 99W) HAS PERSISTED NEAR
17.2N 128.8E, APPROXIMATELY 230 NM SOUTHWEST OF LEGAZPI,
PHILIPPINES. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY
DEPICTS A BROAD AREA OF MID AND UPPER LEVEL CONVECTION ROTATING
ABOUT AN OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC). THE POSITION
IS PLACED BASED ON A 112022Z SSMIS 37GHZ IMAGE THAT DEPICTS
FORMATIVE BANDING WRAPPING INTO THE LLCC AND IS IN AGREEMENT WITH A
111800Z RJTD FIX POSITIONED TO THE SOUTH. NUMERICAL MODELS AGREE
THAT INVEST 99W WILL CONTINUE TO SLOWLY CONSOLIDATE AS IT MOVES
NORTHWESTWARD TOWARDS LUZON OVER THE NEXT 24 HOURS.  MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 13 TO 17 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 LOW.

jrchang5

JTWC 12/23Z提升評級至Medium。

(1) THE AREA OF CONVECTION (INVEST 99W) PREVIOUSLY LOCATED
NEAR 17.5N 127.5E IS NOW LOCATED NEAR 17.8N 125.0E, APPROXIMATELY
196 NM EAST OF APARRI, PHILIPPINES. ANIMATED ENHANCED INFRARED (EIR)
SATELLITE IMAGERY DEPICTS A BROAD LOW LEVEL CIRCULATION WITH WEAK
CONVECTION NEAR THE CENTER AND FLARING CONVECTION SHEARED OVER THE
SOUTHWESTERN SEMICIRCLE. WEAK, FORMATIVE BANDING IS EVIDENT IN A
121938Z SSMI 85GHZ IMAGE. INVEST 99W IS IN AN ENVIRONMENT FAVORABLE
FOR FURTHER DEVELOPMENT WITH LOW (5-10 KTS) VERTICAL WIND SHEAR
(VWS), ESTABLISHED EQUATORWARD OUTFLOW AND WARM (28-29 CELSIUS) SEA
SURFACE TEMPERATURES. NUMERICAL MODELS ARE IN FAIR AGREEMENT THAT
THE SYSTEM WILL CONTINUE TO CONSOLIDATE OVER THE NEXT 24 TO 48 HOURS
BEFORE WEAKENING NORTH OF LUZON WHEREUPON IT WILL DECAY FURTHER
UNTIL IT IS ABSORBED INTO THE MEIYU BOUNDARY.  MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 17 TO 23 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1005 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.

ben811018

擾動９９Ｗ已經抵達菲律賓東方，
即將由西轉西北再轉北進行，
預計明天(14)抵達巴士海峽，
週三(15)從台灣東方近海通過。

由於菲律賓東方的垂直風切增強，
使得９９Ｗ環流結構十分不對稱，
主要雲系偏重於系統的西南側。
未來２４小時，
９９Ｗ有機會短暫增強為熱帶低壓，
但要成為颱風的機會不高。

接下來９９Ｗ行經的巴士海峽、台灣東方近海依然如此，
發展環境受限下，邊走邊減弱，直到消散。

路徑看起來威脅很大，
但９９Ｗ強度實在普普，且環流又不對稱，
主要影響仍以花蓮、台東、恆春、宜蘭為主，
西部地區輕微許多，
只須注意接近通過時，
帶來的水氣讓天氣稍不穩定些。

副熱帶高壓脊

昨晚一段西北的路徑，現在在台灣登陸的機會大增，昨晚風場只掃出 20kt，加上風切加大，相信以 20kt的 LPA登陸機會不小