SPAC: WASI - Post-Tropical

[Nancy Smar]

98P INVEST 200221 0600 12.4S 175.8W SHEM 30 1003

[Nancy Smar]

TROPICAL DISTURBANCE TD10F CENTRE 1005HPA WAS ANALYSED NEAR 12.0S
176.4W AT 210300UTC. POSITION POOR BASED ON HIMAWARI-8 IR/VIS IMAGERY
AND PERIPHERAL SURFACE REPORTS. TD107F MOVING SOUTHEAST AT ABOUT 10
KNOTS.

DEEP CONVECTION CONTINUES TO PERSIST OVER THE SUPPOSED LLCC WITH SOME
PRIMARY BANDS TRYING TO WRAP ONTO SUPPOSED LLCC. SYSTEM LIES UNDER AN
UPPER DIVERGENT AREA IN A LOW SHEARED ENVIRONMENT. CYCLONIC
CIRCULATION EXTENDS UP TO 700HPA. SST AROUND 29 DEGREES CELSIUS.

GLOBAL MODELS HAVE PICKED UP THE SYSTEM AND MOVE IT SOUTHEASTWARDS
INITIALLY AND SOUTHWARDS THEREAFTER WITH SLIGHT INTENSIFICATION.

THE POTENTIAL FOR THIS SYSTEM TO DEVELOP INTO A CYCLONE IN THE NEXT
24 TO 48 HOURS IS MODERATE

[Nancy Smar]

WTPS21 PGTW 210230
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
160 NM EITHER SIDE OF A LINE FROM 11.1S 178.9W TO 13.3S 173.4W
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 27 TO 33 KNOTS. METSAT
IMAGERY AT 210130Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 12.0S 176.7W. THE SYSTEM IS MOVING EAST-SOUTHEASTWARD AT 11
KNOTS.
2. REMARKS:
AN AREA OF CONVECTION (INVEST 98P) HAS PERSISTED NEAR 12.0S 176.7W,
APPROXIMATELY 381 NM WEST-NORTHWESTWARD OF PAGO PAGO, AMERICAN
SAMOA. ANIMATED MULTISPECTRAL SATELLITE IMAGERY, ALONG WITH A
202128Z METOP-B PASS DEPICTS A FORMATIVE LOW LEVEL CIRCULATION
CENTER (LLCC) WITH FRAGMENTED DEEP CONVECTION TO THE NORTHEAST.
ENVIRONMENTAL ANALYSIS REVEALS FAIR CONDITIONS FOR DEVELOPMENT WITH
MODERATE POLEWARD OUTFLOW, WEAK DIFFLUENCE ALOFT, LOW (10 KTS)
VERTICAL WIND SHEAR, AND WARM (29 TO 30 CELSIUS) SEA SURFACE
TEMPERATURES. GLOBAL MODELS INDICATE THAT 98P WILL CONTINUE TO
CONSOLIDATE AND SLIGHTLY INTENSIFY AS IT CONTINUES TO TRACK SOUTH-
SOUTHEASTWARD. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 27
TO 33 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 998
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
220230Z.
//
NNNN

[Nancy Smar]

FKPS01 NFFN 220051
TC ADVISORY
DTG: 20200222/0000Z
TCAC: NFFN
TC: WASI
ADVISORY NR: 2020/1
OBS PSN: 22/0000Z S1342 W17336
CB: WI 90NM OF TC CENTRE TOP FL600
MOV: SE 07KT
C: 995HPA
MAX WIND: 35KT
FCST PSN +6HR: 22/0600 S1400 W17254
FCST MAX WIND +6HR: 45KT
FCST PSN +12HR: 22/1200 S1436 W17218
FCST MAX WIND +12HR: 50KT
FCST PSN +18HR: 22/1800 S1512 W17136
FCST MAX WIND +18HR: 60KT
FCST PSN +24HR: 23/0000 S1606 W17112
FCST MAX WIND +24HR: 65KT
RMK: NIL
NXT MSG: 20200222/0700Z

[Nancy Smar]

SH, 18, 2020021918, , BEST, 0, 95S, 1784E, 15, 1010, DB, 0, , 0, 0, 0, 0, 0, 0, 0, 0, 0, , 0, , 0, 0, INVEST, ,
SH, 18, 2020022000, , BEST, 0, 100S, 1792E, 15, 1010, DB, 0, , 0, 0, 0, 0, 0, 0, 0, 0, 0, , 0, , 0, 0, INVEST, ,
SH, 18, 2020022006, , BEST, 0, 104S, 1798E, 15, 1010, DB, 0, , 0, 0, 0, 0, 0, 0, 0, 0, 0, , 0, , 0, 0, INVEST, ,
SH, 18, 2020022012, , BEST, 0, 111S, 1789W, 15, 1007, DB, 0, , 0, 0, 0, 0, 1007, 100, 50, 0, 0, , 0, , 0, 0, INVEST, ,
SH, 18, 2020022018, , BEST, 0, 114S, 1778W, 20, 1005, DB, 0, , 0, 0, 0, 0, 1007, 100, 40, 0, 0, P, 0, , 0, 0, INVEST, S,
SH, 18, 2020022100, , BEST, 0, 118S, 1768W, 30, 1003, TD, 0, , 0, 0, 0, 0, 1008, 100, 30, 0, 0, P, 0, , 0, 0, INVEST, S,
SH, 18, 2020022106, , BEST, 0, 124S, 1758W, 30, 1003, TD, 0, , 0, 0, 0, 0, 1007, 110, 30, 0, 0, P, 0, , 0, 0, INVEST, S,
SH, 18, 2020022112, , BEST, 0, 129S, 1746W, 70, 987, TY, 34, NEQ, 40, 20, 0, 0, 1009, 160, 30, 0, 0, P, 0, , 0, 0, EIGHTEEN, S, 0, , 0, 0, 0, 0, TRANSITIONED, shC82020 to sh182020,
SH, 18, 2020022112, , BEST, 0, 129S, 1746W, 70, 987, TY, 50, NEQ, 30, 15, 0, 0, 1009, 160, 30, 0, 0, P, 0, , 0, 0, EIGHTEEN, S, 0, , 0, 0, 0, 0, TRANSITIONED, shC82020 to sh182020,
SH, 18, 2020022112, , BEST, 0, 129S, 1746W, 70, 987, TY, 64, NEQ, 10, 10, 0, 0, 1009, 160, 30, 0, 0, P, 0, , 0, 0, EIGHTEEN, S, 0, , 0, 0, 0, 0, TRANSITIONED, shC82020 to sh182020,
SH, 18, 2020022118, , BEST, 0, 129S, 1741W, 55, 996, TS, 34, NEQ, 40, 20, 0, 0, 1009, 160, 30, 0, 0, P, 0, , 0, 0, EIGHTEEN, S,
SH, 18, 2020022118, , BEST, 0, 129S, 1741W, 55, 996, TS, 50, NEQ, 20, 10, 0, 0, 1009, 160, 30, 0, 0, P, 0, , 0, 0, EIGHTEEN, S,
SH, 18, 2020022200, , BEST, 0, 134S, 1733W, 45, 1001, TS, 34, NEQ, 40, 20, 0, 0, 1009, 160, 30, 0, 0, P, 0, , 0, 0, EIGHTEEN, S,

[Nancy Smar]

WTPS32 PGTW 220300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 003//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 003
02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
220000Z --- NEAR 13.4S 173.3W
MOVEMENT PAST SIX HOURS - 125 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
000 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
REPEAT POSIT: 13.4S 173.3W
---
FORECASTS:
12 HRS, VALID AT:
221200Z --- 14.3S 171.9W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
000 NM SOUTHEAST QUADRANT
000 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
010 NM SOUTHWEST QUADRANT
010 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 150 DEG/ 10 KTS
---
24 HRS, VALID AT:
230000Z --- 16.0S 170.9W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
000 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 165 DEG/ 10 KTS
---
36 HRS, VALID AT:
231200Z --- 17.9S 170.4W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
000 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 175 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
240000Z --- 19.6S 170.3W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
000 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 170 DEG/ 09 KTS
---
72 HRS, VALID AT:
250000Z --- 23.3S 169.6W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
---
REMARKS:
220300Z POSITION NEAR 13.6S 172.9W.
22FEB20. TROPICAL CYCLONE 18P (WASI), LOCATED APPROXIMATELY
161 NM WEST-NORTHWEST OF PAGO PAGO, HAS TRACKED SOUTHEASTWARD AT
09 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS DEEP CONVECTION WRAPPING INTO A LOW-LEVEL CIRCULATION
CENTER (LLCC) THAT WAS COINCIDENT WITH AN EYE-LIKE FEATURE IN AN
EARLIER 211752Z WINDSAT 37GHZ MICROWAVE IMAGE. DUE TO DATA LATENCY,
MICROWAVE IMAGES RECEIVED SEVERAL HOURS LATE INDICATED THAT TROPICAL
CYCLONE WASI WAS A SIGNIFICANTLY MORE INTENSE CYCLONE APPROXIMATELY
12 HOURS AGO, SO THE CURRENT INTENSITY OF 45 KNOTS ACTUALLY REFLECTS
A BRIEF WEAKENING TREND. MICROWAVE IMAGERY FROM 6 TO 12 HOURS AGO
INDICATED A MUCH MORE ORGANIZED SYSTEM, DESPITE THE RELATIVELY
DISORGANIZED APPEARANCE ON INFRARED AND VISIBLE SATELLITE IMAGERY.
THE INITIAL POSITION IS PLACED WITH FAIR CONFIDENCE. CURRENT DVORAK
ESTIMATES OF T2.5 TO T3.0 ARE LIKELY AN UNDERESTIMATE, GIVEN THE
SMALL SIZE OF THIS CYCLONE, BUT THE CURRENT INTENSITY IS SUPPORTED BY
A 211954Z METOP-A ASCAT IMAGE DEPICTING A SMALL REGION OF 40-KNOT
WINDS IN THE NORTHEASTERN QUADRANT. VERTICAL WIND SHEAR REMAINS LOW
(5-10 KNOTS) WITH FAIR OUTFLOW AND WARM (28-29 CELSIUS) SEA SURFACE
TEMPERATURES. A BRIEF PERIOD OF RE-INTENSIFICATION IS LIKELY UNTIL
VERTICAL WIND SHEAR GRADUALLY INCREASES THROUGH TAU 72. TC 18P IS
TRACKING ALONG THE SOUTHERN PERIPHERY OF A NEAR EQUATORIAL RIDGE,
FOLLOWING THE SOUTH PACIFIC CONVERGENCE ZONE. BY TAU 24 TO 36, A
SUBTROPICAL RIDGE TO THE EAST WILL SHIFT THE TRACK POLEWARD. HIGH
VERTICAL WIND SHEAR BEYOND TAU 48 WILL CAUSE THE SYSTEM TO WEAKEN AND
BEGIN AN EXTRATROPICAL TRANSITION, WHICH WILL BE COMPLETED BY AROUND
TAU 72. NUMERICAL MODEL GUIDANCE IS IN GOOD OVERALL AGREEMENT WITH
THE JTWC TRACK FORECAST, RESULTING IN GOOD CONFIDENCE IN THE JTWC
TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 220000Z IS 15
FEET. NEXT WARNINGS AT 221500Z AND 230300Z. REFER TO TROPICAL CYCLONE
17P (VICKY) WARNINGS (WTPS31 PGTW) FOR SIX-HOURLY UPDATES.//
NNNN

[Nancy Smar]

CURRENT ESTIMATE
Date (mmddhhmm): 02212106
SATCON: MSLP = 998 hPa MSW = 51 knots
SATCON Member Consensus: 51.0 knots
Pressure -> Wind Using SATCON MSLP: 52 knots
Distance to Outer Closed Isobar Used is 160 nm
Eye Size Correction Used is 0 knots Source: NA
Member Estimates
ADT: 1004 hPa 41 knots Scene: CDO Date: FEB212350
CIMSS AMSU: 988 hPa 63 knots Bias Corr: 0 (MW) Date: 02212106
ATMS: 1003.2 hPa 49.9 knots Date: 02220024
SSMIS: 976.0 hPa 78.0 knots Date: 02211826