TC 18P(WASI) , Invest 99P and Invest 90S: updates at 23/06UTC

TC 18P(WASI) SOUTH PACIFIC
As of 06:00 UTC Feb 23, 2020:
Location: 17.1°S 171.0°W
Maximum Winds: 40 kt ( 75km/h)
Gusts: 50 kt ( 95km/h)
Minimum Central Pressure: 1001 mb
TPPS12 PGTW 230711 COR
A. TROPICAL CYCLONE 18P (WASI)
B. 23/0541Z
C. 16.96S
D. 171.15W
E. FIVE/GOES17
F. T1.5/2.0/W2.0/24HRS  STT: W0.5/03HRS
G. IR/EIR
H. REMARKS: 38A/PBO SBC/ANMTN. CNVCTN WRAPS .30 ON LOG10 SPIRAL
YIELDING A DT OF 1.5. MET/PT AGREE. DBO DT. COR FOR DATE.
I. ADDITIONAL POSITIONS: NONE
MARTIN
REMARKS:
230300Z POSITION NEAR 16.7S 171.3W.
23FEB20. TROPICAL CYCLONE (TC) 18P (WASI), LOCATED APPROXIMATELY
121 NM SOUTH-SOUTHWEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED
SOUTH-SOUTHEASTWARD AT 12 KNOTS (KTS) OVER THE PAST SIX HOURS.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) REVEALS A PARTIALLY-
EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC) WITH THE MAJORITY OF THE
CONVECTION LOCATED TO THE EAST AND NORTH. THE MSI ALONG WITH AN
EXTRAPOLATION OF A 222048Z MHS 89 GHZ MICROWAVE IMAGE PLACE GOOD
CONFIDENCE IN THE INITIAL POSITION WHICH IS LOCATED NEAR THE PGTW
AND KNES FIXES. THE INITIAL INTENSITY OF 40 KTS IS BASED ON A
WEAKENING CONVECTIVE STRUCTURE AND SUPPORTED BY MULTI-AGENCY
DVORAK CURRENT INTENSITY ESTIMATES OF T2.0-3.0 (30-45 KTS). OVER
THE PAST SIX HOURS, TC 18P HAS PICKED UP SPEED AND THE CONVECTION
COVERING THE EASTERN SEMICIRCLE HAS DECREASED. THE SYSTEM IS
TRANSITING ALONG THE SOUTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE
(STR) WHICH ACTS AS THE PRIMARY STEERING FEATURE. AS THE STR RE-
ORIENTS, THE FORECAST TRACK IS EXPECTED TO TURN TO A SOUTHWARD
TRACK THROUGHOUT THE REMAINDER OF THE FORECAST PERIOD.
ENVIRONMENTAL ANALYSIS REVEALS WARM (28-29 CELSIUS) SEA SURFACE
TEMPERATURES (SST), LOW (5-10 KT) VERTICAL WIND SHEAR (VWS), AND
GOOD POLEWARD AND FAIR EQUATORWARD OUTFLOW. THESE CONDITIONS
SHOULD ALLOW TC 18P A BRIEF PERIOD OF INTENSIFICATION IN THE NEAR-
TERM. AFTER THAT, AS VWS INCREASES AND SST COOL, THE SYSTEM WILL
WEAKEN AND BEGIN TO INTERACT WITH THE STRONG SUBTROPICAL WESTERLY
FLOW. THIS INTERACTION WILL FURTHER INCREASE THE VWS AND CAUSE TC
18P TO TRANSITION TO A SUBTROPICAL CYCLONE BY TAU 48. ALL
NUMERICAL MODEL GUIDANCE SUPPORTS THIS TRACK SCENARIO WITH GOOD
CONFIDENCE. THE JTWC FORECAST TRACK IS PLACED NEAR THE MULTI-MODEL
CONSENSUS WITH GOOD CONFIDENCE. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
230000Z IS 12 FEET. NEXT WARNINGS AT 230900Z, 231500Z, 232100Z AND
240300Z.//
NNNN

INVEST 99P SOUTH PACIFIC
As of 06:00 UTC Feb 23, 2020:
Location: 14.4°S 138.9°E
Maximum Winds: 30 kt ( 55km/h)
Gusts: 40 kt ( 75km/h)
Minimum Central Pressure: 1000 mb
TPPS13 PGTW 230624
A. TROPICAL DISTURBANCE 99P (GULF OF CARPENTARIA)
B. 23/0550Z
C. 14.41S
D. 138.87E
E. FIVE/HMWRI8
F. T2.0/2.0/D1.0/24HRS  STT: D0.5/03HRS
G. IR/EIR/VIS/MSI
H. REMARKS: 49A/PBO PTLY XPSD LLCC/ANMTN. CNVCTN WRAPS .35 ON
LOG10 SPIRAL YIELDING A DT OF 2.0. MET/PT AGREE. DBO DT.
I. ADDITIONAL POSITIONS: NONE
MARTIN
ABPW10 PGTW 230600
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
  B. TROPICAL DISTURBANCE SUMMARY:
      (1) THE AREA OF CONVECTION (INVEST 99P) PREVIOUSLY LOCATED
NEAR 13.6S 138.2E IS NOW LOCATED NEAR 14.5S 138.3E, APPROXIMATELY
141 NM NORTH-NORTHWEST OF MORNINGTON ISLAND, AUSTRALIA. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY AND A 230010Z AMSU 89GHZ MICROWAVE
IMAGE SHOW A BROAD, SLIGHTLY ELONGATED LOW LEVEL CIRCULATION (LLC)
WITH POTENTIAL FORMATIVE BANDING TO THE NORTH AND SOUTH. A 222255Z
METOP-A ASCAT PASS REVEALS 25 TO 30 KNOT WINDS FULLY SURROUNDING,
BUT STILL DISPLACED FROM, THE BROAD LLC. 99P REMAINS IN A VERY
FAVORABLE ENVIRONMENT WITH DEVELOPING DUAL CHANNEL OUTFLOW, LOW (5
TO 10 KNOT) VERTICAL WIND SHEAR, AND WARM (31 TO 32 CELSIUS) SEA
SURFACE TEMPERATURE. GLOBAL MODELS ARE IN GOOD AGREEMENT THAT 99P
WILL CONTINUE TO TRACK SLOWLY SOUTH-SOUTHWESTWARD, INTENSIFYING TO
WARNING THRESHOLD WITHIN THE NEXT 24 HOURS. GLOBAL MODELS INDICATE
THAT AFTER MAKING LANDFALL, 99P WILL BEGIN TO TRACK WESTWARD OVER
THE AUSTRALIAN NORTHERN TERRITORY. MAXIMUM SUSTAINED SURFACE WINDS
ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1001 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS HIGH.
SEE REF B (WTPS21 PGTW 230330) FOR FURTHER DETAILS.


TC 17P(VICKY) SOUTH PACIFIC
As of 06:00 UTC Feb 23, 2020:
Location: 22.5°S 168.9°W
Maximum Winds: 25 kt
Minimum Central Pressure: 1004 mb

INVEST 90S SOUTH INDIAN
As of 06:00 UTC Feb 23, 2020:
Location: 12.4°S 119.1°E