老農民版夜神月

  熱帶低壓  
編號：09 F ( 20 P )
名稱：無

  基本資料  
擾動編號日期：2021 年 02 月 07 日 08 時
JTWC升格日期:2021 年 02 月 10 日 08 時
撤編日期　　：2021 年 02 月 12 日 14 時
登陸地點　　：無

  巔峰時期資料  
近中心最強風速
斐濟氣象局 (FMS)：30 kt
聯合颱風警報中心(JTWC)：45 kt ( TS )
海平面最低氣壓   ：991 百帕

  擾動編號資料  
92P.INVEST.15kts.1006mb.15S.179E

以上資料來自：FMS、JTWC、颱風論壇整理製作

dom

已完全轉化消散，FNMOC撤編

老農民版夜神月

JTWC將10/18Z起的20P性質改為SS（副熱帶氣旋）

SH, 20, 2021021012,   , BEST,   0, 284S, 1767W,  40,  992, TS,  34, NEQ,  200,  165,  120,   65, 1005,  185,  60,   0,   0,   P,   0,    ,   0,   0,     TWENTY, M,
SH, 20, 2021021018,   , BEST,   0, 302S, 1763W,  35,  993, SS,  34, NEQ,  190,  165,  110,   95, 1005,  185,  60,   0,   0,    ,   0,    ,   0,   0,     TWENTY,  ,
SH, 20, 2021021100,   , BEST,   0, 326S, 1755W,  35,  996, SS,  34, NEQ,  190,  165,  110,   95, 1005,  185,  60,   0,   0,    ,   0,    ,   0,   0,     TWENTY,  ,

老農民版夜神月

JTWC認為逐漸轉化中,而NOAA已直接分析定性為溫帶氣旋

SH, 20, 2021021018, , BEST, 0, 302S, 1763W, 35, 993, TS, 34, NEQ, 190, 165, 110, 95, 1005, 185, 60, 0, 0, , 0, , 0, 0, TWENTY, ,

TXPS27 KNES 101803
TCSWSP

A. 20P (NONAME)

B. 10/1730Z

C. 29.6S

D. 176.5W

E. THREE/HIMAWARI-8

F. EXTRATROPICAL

G. IR/EIR/SWIR

H. REMARKS...THIS ESTIMATE WAS DERIVED USING 4 KM IR DATA. THE SYSTEM
HAS UNDERGONE EXTRA TROPICAL TRANSITION LEAVING AN EXPOSED LLCC AND
RAPIDLY WEAKENING CONVECTION. THIS WILL BE THE FINAL BULLETIN.

I. ADDL POSITIONS

NIL


...TUGGLE

老農民版夜神月

JTWC1500Z發布Final Warning

dom

JTWC06Z定強40節並預測已達到巔峰，逐漸南下減弱

WTPS31 PGTW 100900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 20P (TWENTY) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 20P (TWENTY) WARNING NR 002
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   100600Z --- NEAR 26.7S 177.4W
     MOVEMENT PAST SIX HOURS - 170 DEGREES AT 16 KTS
     POSITION ACCURATE TO WITHIN 040 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 165 NM NORTHEAST QUADRANT
                            135 NM SOUTHEAST QUADRANT
                            080 NM SOUTHWEST QUADRANT
                            070 NM NORTHWEST QUADRANT
   REPEAT POSIT: 26.7S 177.4W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   101800Z --- 29.9S 176.4W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING EXTRATROPICAL
   RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
                            160 NM SOUTHEAST QUADRANT
                            070 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 155 DEG/ 18 KTS
    ---
   24 HRS, VALID AT:
   110600Z --- 33.1S 174.7W
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING EXTRATROPICAL
   RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
                            160 NM SOUTHEAST QUADRANT
                            070 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 145 DEG/ 18 KTS
    ---
   36 HRS, VALID AT:
   111800Z --- 36.1S 172.3W
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   EXTRATROPICAL
    ---
REMARKS:
100900Z POSITION NEAR 27.5S 177.1W.
10FEB21. TROPICAL CYCLONE 20P (TWENTY), LOCATED APPROXIMATELY 566
NM SOUTH-SOUTHEAST OF SUVA, FIJI, HAS TRACKED SOUTHWARD AT 16
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS A WELL DEFINED AND PARTIALLY EXPOSED LOW LEVEL
CIRCULATION CENTER (LLCC), WITH MODERATE CONVECTION DISPLACED TO THE
SOUTHEAST. THE OVERALL DEPICTION IN THE MSI IS INCREASINGLY
EXTRATROPICAL, WITH THE COMMA-SHAPED CONVECTIVE ENVELOPE NOW
POLEWARD AND EASTWARD OF THE LLCC. A TIMELY 100600Z GMI 36GHZ
MICROWAVE IMAGE WITH A WELL-DEFINED LOW EMISSIVITY REGION AND LOW
LEVEL CONVECTIVE BANDING FEATURES LENT HIGH CONFIDENCE TO THE
INITIAL POSITION. THE INITIAL INTENSITY IS LOWERED TO 40 KNOTS WITH
FAIR CONFIDENCE BASED ON A BLEND OF A DVORAK CURRENT INTENSITY
ESTIMATE OF T2.5 (35 KTS) FROM PGTW, AND AN ADT ESTIMATE OF T3.0 (45
KTS), AS WELL AS AN EXTRAPOLATION OF 100116Z AMSR2 WINDSPEED
ANALYSIS WHICH SHOWED 40-50KT WINDS CONFINED TO THE SOUTHEAST
QUADRANT, WITH 35-40KT WINDS ELSEWHERE.
TC 20P IS MOVING RAPIDLY SOUTHWARD ALONG TIGHT GRADIENT BETWEEN THE
STR TO THE EAST AND DEEP MID-LATITUDE TROUGH TO THE WEST. THE
OVERALL ENVIRONMENT IS NOT SUPPORTIVE OF TROPICAL CYCLONE
DEVELOPMENT, WITH COOL (24-26C) SSTS, VERY HIGH (>30KT) VWS AND
ROBUST POLEWARD OUTFLOW. THERMAL CROSS-SECTION AND THICKNESS
ANALYSIS REVEALS THE SYSTEM HAS BOTH TROPICAL AND EXTRATROPICAL
FEATURES AT WARNING TIME. AS THE SYSTEM CONTINUES MOVING SOUTH-
SOUTHEASTWARD IT WILL ENCOUTER INCREASINGLY UNFAVORABLE CONDITIONS,
AND BECOME EMBEDDED IN THE BAROCLINIC ZONE UNDER THE UPPER-LEVEL
JET, TRANSITIONING TO A FULLY EXTRATROPICAL SYSTEM AT OR BEFORE TAU
36. NUMERICAL MODEL GUIDANCE IS IN VERY GOOD AGREEMENT THROUGH THE
FORECAST PERIOD LENDING HIGH CONFIDENCE TO THE JTWC FORECAST TRACK,
WHICH REMAINS CONSISTENT WITH THE PREVIOUS WARNING, NEAR THE MULTI-
MODEL CONSENSUS MEAN. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 100600Z IS
18 FEET. NEXT WARNINGS AT 101500Z, 102100Z, 110300Z AND 110900Z.//
NNNN

老農民版夜神月

19Z的風場掃描其實已掃出大面積40~45KT
也證明JTWC18Z時在已經連續4報T2.5的情況下破例沒有升格著實是昏招

老農民版夜神月

FMSZ00Z則依舊把發展機會維持在低至中等

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
ISSUED FROM RSMC NADI Feb 100010 UTC.

TROPICAL DEPRESSION TD09F [996HPA] WAS ANALYSED NEAR 24.6S 177.8W AT
102100UTC. POSITION POOR BASED ON HIMAWARI-8 EIR IMAGERY AND
PERIPHERY REPORTS. MAXIMUM 10-MINUTE AVERAGE WINDS UP TO 30 KNOTS
NEAR THE CENTRE. DEPRESSION MOVING SOUTH-SOUTHEAST AT ABOUT 15 KNOTS.


TD09F SLOW MOVING AND EXPECTED TO SLOWLY DRIFT SOUTH. DEEP CONVECTION
SHEARED TO THE EAST OF SUPPOSED LLCC. ORGANISATION REMAINS POOR. THE
SYSTEM LIES TO THE EAST OF AN UPPER LEVEL TROUGH IN A MODERATE TO
HIGH SHEARED ENVIRONMENT. SST AROUND 27 DEGREES.

TD09F IS STEERED TO THE SOUTH BY THE NORTHWESTERN PERIPHERY OF THE
NEAR EQUATORIAL RIDGE LOCATED TO THE NORTHEAST OF THE SYSTEM.

POTENTIAL FOR TD09F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT 24
TO 48 HOURS IS LOW TO MODERATE.