老農民版夜神月

EC於方才熱騰騰剛出爐的29/12Z報,和昨日的預報相比.
修改成了相對簡單,一路向西北西移動直到登陸消散的路徑


而JMA的天氣預測圖中
+24H(30/12Z)時91W尚維持為LPA(低壓區)
+48H(31/12Z)時則已升格成為熱帶性低氣壓

hokjar1212

JTWC 提升評級至Medium

(1) THE AREA OF CONVECTION (INVEST 91W) PREVIOUSLY LOCATED
NEAR 15.8N 118.7E IS NOW LOCATED NEAR 16.6N 115.6E, APPROXIMATELY
325 NM NORTHWEST OF MANILA, PHILIPPINES. THE SYSTEM IS BEING
ASSESSED AS A MONSOON DEPRESSION. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY AND A 301322Z METOP-B 89 GHZ MICROWAVE IMAGE DEPICT A VERY
BROAD (>150 NM) LOW LEVEL CIRCULATION (LLC). ASCAT-B DATA FROM THE
301322Z PASS FURTHER DEPICTS WEAK (10-15 KTS) WINDS AROUND THE
CENTER OF THE ELONGATED CIRCULATION WHICH COVERS MOST OF THE SOUTH
CHINA SEA (SCS). THE CONVECTION IS SHALLOW, DISORGANIZED AND
FLARING. ENVIRONMENTAL ANALYSIS REVEALS GOOD POLEWARD OUTFLOW ALOFT,
LOW (<15 KTS) VERTICAL WIND SHEAR, AND WARM (29-31C) SEA SURFACE
TEMPERATURES AND IS CONDUCIVE FOR FURTHER DEVELOPMENT. GLOBAL MODELS
ARE IN GENERAL AGREEMENT THAT INVEST 91W WILL CONTINUE TO TRACK WEST-
NORTHWESTWARD IN THE SCS WHERE IT WILL SLOWLY CONSOLIDATE AND
INTENSIFY. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1004 MB.
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.

老農民版夜神月

把EC和GFS於30/12Z的最新報相比較,在91W上兩方分歧已經甚微
但在91W通過海南島,進入北部灣後.GFS認為南海北部會再逐漸生成一個季風系統

霧峰追風者

熱帯低気圧
令和02年07月31日10時15分 発表

<31日09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 16度55分(16.9度)
東経 113度05分(113.1度)
進行方向、速さ        西北西 20km/h(10kt)
中心気圧        1000hPa
最大風速        15m/s(30kt)
最大瞬間風速        23m/s(45kt)

<31日21時の予報>
強さ        -
熱帯低気圧
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 112度00分(112.0度)
進行方向、速さ        西北西 10km/h(6kt)
中心気圧        996hPa
最大風速        15m/s(30kt)
最大瞬間風速        23m/s(45kt)
予報円の半径        110km(60NM)

<01日09時の予報>
強さ        -
存在地域        南シナ海
予報円の中心        北緯 17度55分(17.9度)
東経 110度40分(110.7度)
進行方向、速さ        西北西 15km/h(7kt)
中心気圧        994hPa
最大風速        18m/s(35kt)
最大瞬間風速        25m/s(50kt)
予報円の半径        150km(80NM)

jrchang5

CWB 31/00Z亦跟進升格為TD04。

熱帶性低氣壓TD04
現況
2020年07月31日08時

中心位置在北緯 17.0 度，東經 113.0 度
過去移動方向 -
過去移動時速 -公里
中心氣壓 1000百帕
近中心最大風速每秒 15 公尺
瞬間最大陣風每秒 23 公尺
預測
預測 12 小時平均移向移速為

西北西 時速 10 公里
預測 07月31日20時
中心位置在北緯 17.4 度，東經 112.0 度
中心氣壓1000百帕
近中心最大風速每秒 15 公尺
瞬間最大陣風每秒 23 公尺
70%機率半徑 110 公里
預測 12-24 小時平均移向移速為

西北西 時速 6 公里
預測 08月01日08時
中心位置在北緯 17.6 度，東經 111.3 度
中心氣壓998百帕
近中心最大風速每秒 18 公尺
瞬間最大陣風每秒 25 公尺
七級風暴風半徑 180 公里
70%機率半徑 170 公里
預測 24 小時有發展為輕度颱風的趨勢

ben811018

低層依然慘烈...

jrchang5

JTWC 31/1830Z發布TCFA。

WTPN21 PGTW 311830
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 91W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 17.3N 112.8E TO 20.0N 107.1E
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 20 TO 25 KNOTS. METSAT
IMAGERY AT 311200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 17.2N 112.0E. THE SYSTEM IS MOVING WESTWARD AT 06 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 91W) PREVIOUSLY LOCATED
NEAR 17.4N 112.6E IS NOW LOCATED NEAR 17.2N 112.0E, APPROXIMATELY
191 NM SOUTH-SOUTHEAST OF HAIKOU, HAINAN. THIS DISTURBANCE IS
CURRENTLY ASSESSED AS A MONSOON DEPRESSION. ANIMATED ENHANCED
INFRARED SATELLITE IMAGERY DEPICTS A BROAD LOW LEVEL CIRCULATION
(LLC) WITH PERSISTENT DEEP CONVECTION ALONG THE SOUTHERN SEMICIRCLE
AND FRAGMENTED DEEP CONVECTION EXTENDING EASTWARD. A 311326Z METOP-B
ASCAT PASS SHOWS THAT 91W HAS BEGUN TO CONSOLIDATE AND REVEALS A
GENERALLY ASYMMETRIC LLC WITH A BAND OF 20 TO 25 KNOT WINDS TO THE
SOUTHWEST AND WEAKER WINDS TO THE NORTH. 91W IS CURRENTLY IN A
FAVORABLE ENVIRONMENT WITH EXCELLENT EQUATORWARD OUTFLOW, LOW (5-10
KNOT) VERTICAL WIND SHEAR, AND VERY WARM (31 CELSIUS) SEA SURFACE
TEMPERATURES. GLOBAL MODELS ARE IN VERY GOOD AGREEMENT THAT 91W WILL
CONTINUE TO TRACK WEST-NORTHWESTWARD INTO THE GULF OF TONKIN WHILE
CONTINUING TO CONSOLIDATE, POTENTIALLY REACHING WARNING THRESHOLD
WITHIN THE NEXT 36 HOURS. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1004 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
011830Z.//
NNNN

老農民版夜神月

JTWC發布TCFA