霧峰追風者

  二級熱帶氣旋  
編號：03 U ( 96 S )
名稱 : Dahlia

  基本資料  
擾動編號日期：2017 年 11 月 23 日 22 時
升格熱低日期：2017 年 11 月 25 日 20 時
命名日期　　：2017 年 11 月 29 日 20 時
JTWC升格日期:2017 年 11 月 30 日 08 時
撤編日期　　：2017 年 12 月 08 日 01 時
登陸地點　　：無

  巔峰時期資料  
澳洲氣象局(BoM)：50 kt ( TS )
印尼雅加達氣象局(BMKG)：50 kt
聯合颱風警報中心(JTWC)：50 kts ( TS )
海平面最低氣壓：987 百帕

  過去路徑圖  

  擾動編號資料  
96S.INVEST.20kts.1007mb.4.3S.93.7E


以上資料來自：BoM、BMKG、JTWC、颱風論壇整理製作

霧峰追風者

JTWC 17Z評級Low

(1) AN AREA OF CONVECTION (INVEST 96S) HAS PERSISTED NEAR
4.2S 93.6E, APPROXIMATELY 522 NM WEST-SOUTHWEST OF SUMATRA.
ANIMATED ENHANCED INFRARED IMAGERY DEPICTS FLARING, DISORGANIZED
CONVECTION TO THE NORTH AND WEST OF THE LOW LEVEL CIRCULATION (LLC)
WITH OVERALL BROAD MIDLEVEL TURNING. A 231518Z 89 GHZ AMSU IMAGE
FURTHER REVEALS A POORLY-ORGANIZED LLC. UPPER LEVEL ANALYSIS SHOWS
WEAK EQUATORWARD OUTFLOW WITH GOOD DIVERGENCE ALOFT, HIGH (25-30
KNOT) VERTICAL WIND SHEAR, AND FAVORABLE SEA SURFACE TEMPERATURES
(29-30 CELSIUS). GLOBAL MODELS SHOW THE SYSTEM MOVING SLOWLY TO THE
SOUTH WITH AN UNLIKELY CHANCE OF DEVELOPMENT OVER THE NEXT SEVERAL
DAYS.  MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB.
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS LOW.

周子堯@FB

JTWC 13z評級提升至Medium

(1) THE AREA OF CONVECTION (INVEST 96S) PREVIOUSLY LOCATED
NEAR 4.2S 93.6E, IS NOW LOCATED NEAR 6.7S 93.1E, APPROXIMATELY 391
NM NORTHWEST OF COCOS ISLAND. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS FLARING CONVECTION OVER A PARTIALLY COVERED LOW
LEVEL CIRCULATION CENTER (LLCC). A 250951Z 91GHZ SSMIS MICROWAVE
IMAGE REVEALS FORMATIVE BANDING AND THE MAJORITY OF THE DEEP
CONVECTION LOCATED TO THE WEST OF THE LLCC. A 250341Z PARTIAL ASCAT
PASS INDICATES 20 KNOT WINDS IN THE SOUTHWESTERN QUADRANT, AND AN
ISOLATED AREA OF 25 KNOT WINDS. POLEWARD OUTFLOW HAS STRENGTHENED,
ENHANCING CONVECTION AND DIVERGENCE ALOFT. MODERATE (10-20 KNOT)
VERTICAL WIND SHEAR (VWS) IS STIFLING DEVELOPMENT, AND VWS VALUES
INCREASE SHARPLY TO THE WEST. WARM (28-29 CELSIUS) SEA SURFACE
TEMPERATURES (SSTS) ARE FAVORABLE, WITH A TIGHT SST GRADIENT TOWARDS
LOWER TEMPERATURES TO THE SOUTH. GLOBAL MODELS DIFFER AS TO THE
TIMING AND DEGREE OF INTENSIFICATION. SOME MODELS PORTRAY NEAR-TERM
LIMITED DEVELOPMENT, WHILE OTHERS PROJECT INTENSIFICATION IN THE
LATER TAUS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 23 TO
28 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.

霧峰追風者

BMKG 12Z升格熱帶低壓，並開始發報。

SITUATION
At 12:00 UTC Tropical Depression TD96S 1005 hPa was within 30 nautical miles of 5,8 S 93,4 E moving southwest at 10 knots.

This tropical depression may develop into a Tropical Cyclone in the next 6-12 hours.


FORECAST
Clockwise winds reaching 20 knots expected to increase to 25 knots in the next 24 hours.
High seas may exceed Rough to Very Rough scale and rising swell.

00:00 UTC 26 November:  Within 60 nautical miles of 6,6 S 92,5 E
                        Central pressure 1003 hPa.
                        Wind speed reaching 20 knots near centre.
12:00 UTC 26 November: Within 90 nautical miles of 7,3 S 91,4 E
                        Central pressure 1002 hPa.
                        Wind speed reaching 25 knots near centre.

REMARKS
Ships please transmit 3-hourly weather reports.
Next warning will be issued by 19:00 UTC 25 November 2017.

Tropical Cyclone Warning Centre JAKARTA

霧峰追風者

TPXS11 PGTW 251819
A. TROPICAL DISTURBANCE 96S (SW OF SUMATRA)
B. 25/1800Z
C. 7.01S
D. 92.76E
E. FIVE/HMWRI8
F. T1.5/1.5  STT: S0.0/03HRS
G. IR/EIR
H. REMARKS: 38A/PBO SBC/ANMTN. .30 WRAP ON LOG10 SPIRAL YIELDS
A 1.5 DT. MET AND PT ARE UNAVAILABLE. DBO DT.
I. ADDITIONAL POSITIONS: NONE

   BERMEA

TXXS29 KNES 251852
TCSSIO
A.  TROPICAL DISTURBANCE (96S)
B.  25/1730Z
C.  6.4S
D.  92.9E
E.  THREE/HIMAWARI-8
F.  T2.0/2.0/D1.5/24HRS
G.  IR/EIR/SWIR
H.  REMARKS...SHEAR PATTERN. CIRCULAR LL CLOUDS AND A CENTER NEAR TO A
SMALL AREA OF ACTIVE CONVECTION YIELDS A DT OF 2.0. MET IS 1.5 AND PT
IS 2.0. FT IS BASED ON DT.
I.  ADDL POSITIONS
    NIL

...RAMIREZ

t02436

BoM開始發報，展望中已編號03U。

A second tropical low (03U lies north of the region near 7.6S 98.6E. It is expected to move generally southeast during the next few days, and it may develop as it does so, possibly reaching tropical cyclone intensity from Thursday. Its likely to enter the Western Region, to the south of Java on Friday.
From Thursday the system may move close to Christmas Island leading to a period of gusty winds, increased shower and thunderstorm activity and rough seas.

Likelihood of this system being a tropical cyclone in the Western Region on:
Wednesday:Very Low
Thursday: Low
Friday:High

霧峰追風者

JTWC 04Z發佈TCFA，逐漸增強。

WTXS22 PGTW 290430
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
155 NM EITHER SIDE OF A LINE FROM 8.5S 100.7E TO 10.3S 107.5E
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 25 TO 30 KNOTS. METSAT IMAGERY AT
290400Z INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 8.5S
101.0E. THE SYSTEM IS MOVING EASTWARD AT 06 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 96S) PREVIOUSLY LOCATED
NEAR 8.4S 101.2E IS NOW LOCATED NEAR 8.5S 101.0E, APPROXIMATELY
300NM WEST-NORTHWEST OF CHRISTMAS ISLAND, AUSTRALIA. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY DEPICTS A BROAD LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH FORMATIVE CONVECTIVE BANDING OVER THE
WESTERN SEMI-CIRCLE. A 282328Z WINDSAT 37GHZ IMAGE SHOWS A
CONSOLIDATING LLCC WITH IMPROVED BANDING WRAPPING INTO A DEFINED
CENTER. A 290312Z ASCAT IMAGE SHOWS NUMEROUS 30-KNOT WINDS
ASSOCIATED WITH THE PRIMARY CONVECTIVE BAND. UPPER-LEVEL ANALYSIS
INDICATES A MARGINALLY-FAVORABLE ENVIRONMENT WITH MODERATE TO STRONG
(25 TO 35 KNOTS) VERTICAL WIND SHEAR OFFSET BY GOOD POLEWARD
OUTFLOW. GLOBAL DYNAMIC MODELS INDICATE THAT 96S WILL STEADILY
DEVELOP WHILE TRACKING EAST-SOUTHEASTWARD TO SOUTHEASTWARD INTO A
MORE FAVORABLE UPPER-LEVEL ENVIRONMENT OVER THE NEXT 2 DAYS. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1000 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
300430Z.//
NNNN

Meow

BMKG忙翻了，好不容易6小時前降Cempaka到TD，現在又命名Dahlia。

SITUATION
At 12:00 UTC Tropical Cyclone DAHLIA 998 hPa was within 30 nautical miles of 8,5 S 100,8 E moving west at 2 knots.

FORECAST
Clockwise winds reaching 35 knots expected to decrease to 45 knots in the next 24 hours.
High seas may exceed Rough to Very Rough scale and rising swell.

00:00 UTC 30 November:  Within 60 nautical miles of 8,8 S 100,6 E
                        Central pressure 996 hPa.
                        Wind speed reaching 40 knots near centre.
12:00 UTC 30 November: Within 90 nautical miles of 9,4 S 102,2 E
                        Central pressure 995 hPa.
                        Wind speed reaching 45 knots near centre.