W環

JTWC: MEDIUM

THE AREA OF CONVECTION (INVEST 91P) PREVIOUSLY LOCATED
NEAR 17.3S 175.4W, IS NOW LOCATED NEAR 16.8S 173.8W, APPROXIMATELY
240 NM SOUTHWEST OF PAGO PAGO, AMERICAN SAMOA. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS PERSISTENT DEEP
CONVECTION WITH AN INCREASE OF FORMATIVE BANDING WRAPPING INTO A
BROAD LOW-LEVEL CIRCULATION CENTER (LLCC). A 071828Z SSMIS 91 GHZ
IMAGE SHOWS DEEP CONVECTIVE BANDING OVER THE SOUTHERN SEMI-CIRCLE,
AND SUGGESTS THE LLCC IS MORE WELL DEFINED THAN SEEN IN THE MSI
PRESENTATION. A 070912Z ASCAT IMAGE SHOWS 25 TO 30 KNOT GRADIENT
WINDS ALONG THE SOUTHERN PERIPHERY OF THE CIRCULATION WITH 15 TO 20
KNOTS OVER THE NORTHERN SEMI-CIRCLE. UPPER-LEVEL ANALYSIS INDICATES
A MARGINALLY FAVORABLE ENVIRONMENT WITH LOW TO MODERATE VERTICAL
WIND SHEAR AND DIFFLUENT FLOW. EASTERLY GRADIENT FLOW INTO TROPICAL
CYCLONE 18P (DONNA), APPROXIMATELY 1200 NM TO THE WEST, IS CURRENTLY
AIDING IN SPINNING UP THIS LLCC, HOWEVER THIS EFFECT SHOULD EASE AS
18P MOVES FURTHER SOUTH, LEAVING ONLY A SMALL WINDOW FOR POTENTIAL
DEVELOPMENT. DYNAMIC MODELS GENERALLY INDICATE WEAK DEVELOPMENT AND
A QUASISTATIONARY TRACK MOTION OVER THE NEXT TWO DAYS. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB. DUE TO IMPROVED
ORGANIZATION OF THE LLCC IN MICROWAVE IMAGERY, THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.

t02436

JTWC發布TCFA

W環

升19P

TROPICAL CYCLONE 19P (NINETEEN) WARNING NR 001   
   02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   090000Z --- NEAR 15.3S 172.9W
     MOVEMENT PAST SIX HOURS - 290 DEGREES AT 05 KTS
     POSITION ACCURATE TO WITHIN 020 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            035 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   REPEAT POSIT: 15.3S 172.9W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   091200Z --- 15.0S 174.4W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 275 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   100000Z --- 14.9S 176.3W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 265 DEG/ 10 KTS
    ---
   36 HRS, VALID AT:
   101200Z --- 15.0S 178.3W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 260 DEG/ 07 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   110000Z --- 15.2S 179.8W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            035 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 240 DEG/ 06 KTS
    ---
   72 HRS, VALID AT:
   120000Z --- 16.4S 178.2E
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 96 HR POSIT: 155 DEG/ 01 KTS
    ---
   LONG RANGE OUTLOOK:
    ---
   96 HRS, VALID AT:
   130000Z --- 16.8S 178.4E
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   RADIUS OF 034 KT WINDS - 025 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            025 NM NORTHWEST QUADRANT
   VECTOR TO 120 HR POSIT: 105 DEG/ 01 KTS
    ---
   120 HRS, VALID AT:
   140000Z --- 16.9S 178.8E
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
    ---

Meow

南太平洋首見5月命名雙旋，不包含移動到澳洲責任區才命名的系統。