Overall Green alert Tropical Cyclone for WASI-20
in Samoa, Niue

Global Telecommunication Service

GTS (Global Telecommunication Service) is the official Warning and Alerting channel by the World Meteorological Organization (WMO) adopted by several Warning Organizations. As soon as a new GTS message regarding Tropical Cyclones(WT) or Tsunami(WE) the messages are processed and possibly assigned to the specific event. When a new GTS message is present an new tab in the specific event report page is present.The presence of a GTS message is shown in the homepage with a dedicated icon.

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2020-02-23 13:28

WTPS32 PGTW 231500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 009//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 009
   02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   231200Z --- NEAR 17.2S 171.0W
     MOVEMENT PAST SIX HOURS - 160 DEGREES AT 06 KTS
     POSITION ACCURATE TO WITHIN 060 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   REPEAT POSIT: 17.2S 171.0W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   240000Z --- 18.8S 170.5W
   MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
231500Z POSITION NEAR 17.6S 170.9W.
23FEB20. TROPICAL CYCLONE (TC) 18P (WASI), LOCATED APPROXIMATELY 130
NM NORTH-NORTHWEST OF NIUE, HAS TRACKED SOUTH-SOUTHEASTWARD AT 06
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY AND A 231205Z ATMS 88GHZ IMAGE INDICATE A RAPIDLY WEAKENING
LOW-LEVEL CIRCULATION WITH ISOLATED CONVECTION DISPLACED TO THE
SOUTH. A 230805Z ASCAT-A IMAGE DEPICTS A WEAKLY DEFINED CIRCULATION
(AT BEST) EMBEDDED WITHIN AN EXTENSIVE REGION OF NORTHERLY FLOW;
NORTHERLY WINDS ALONG THE EASTERN PERIPHERY VARY FROM 15 TO 25
KNOTS. THE REMNANTS OF TC 18P WILL CONTINUE TRACKING SOUTH-
SOUTHEASTWARD ALONG THE WESTERN PERIPHERY OF A LOW-LEVEL SUBTROPICAL
RIDGE. NUMERICAL MODEL GUIDANCE REMAINS IN GOOD AGREEMENT,
THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. THIS
IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT TYPHOON WRNCEN
PEARL HARBOR HI. THE SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF
REGENERATION. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 231200Z IS 10 FEET.
REFER TO TROPICAL CYCLONE 19P (NINETEEN) WARNINGS (WTPS31 PGTW) FOR
SIX-HOURLY UPDATES.//

>

2020-02-23 08:14

WTPS32 PGTW 230900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 008//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 008
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   230600Z --- NEAR 17.0S 171.0W
     MOVEMENT PAST SIX HOURS - 160 DEGREES AT 11 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 - 055 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            055 NM NORTHWEST QUADRANT
   REPEAT POSIT: 17.0S 171.0W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   231800Z --- 18.9S 170.4W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            055 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 165 DEG/ 08 KTS
    ---
   24 HRS, VALID AT:
   240600Z --- 20.5S 170.0W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            050 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 170 DEG/ 09 KTS
    ---
   36 HRS, VALID AT:
   241800Z --- 22.2S 169.7W
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING SUBTROPICAL
   RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 175 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   250600Z --- 23.9S 169.5W
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   SUBTROPICAL
   RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            050 NM SOUTHWEST QUADRANT
                            070 NM NORTHWEST QUADRANT
    ---
REMARKS:
230900Z POSITION NEAR 17.5S 170.8W.
23FEB20. TROPICAL CYCLONE (TC) 18P (WASI), LOCATED APPROXIMATELY 163
NM SOUTH OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED SOUTH-
SOUTHEASTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED
INFRARED SATELLITE IMAGERY DEPICTS FLARING DEEP CONVECTION OVER A
PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION CENTER (LLCC). A 230448Z
SSMIS 91GHZ MICROWAVE IMAGE, HOWEVER, INDICATES CURVED BANDING OVER
THE SOUTHERN SEMICIRCLE WRAPPING INTO THE WESTERN QUADRANT OF A
BROAD BUT DEFINED LLCC, WHICH SUPPORTS THE INITIAL POSITION WITH
GOOD CONFIDENCE. TC 18P IS FORECAST TO CONTINUE TRACKING SOUTH-
SOUTHEASTWARD ALONG THE WESTERN PERIPHERY OF A LOW- TO MID-LEVEL
SUBTROPICAL RIDGE (STR) THROUGH THE FORECAST PERIOD. NUMERICAL MODEL
GUIDANCE REMAINS IN GOOD AGREEMENT, THEREFORE, THERE IS HIGH
CONFIDENCE IN THE JTWC FORECAST TRACK. TC 18P IS CURRENTLY LOCATED
UNDER MODERATE UPPER-LEVEL NORTHWESTERLY FLOW, WHICH IS HINDERING
CONVECTIVE DEVELOPMENT, AND IS FORECAST TO TRACK UNDER INCREASING
VERTICAL WIND SHEAR (25 TO 30 KNOTS) AFTER TAU 24 ASSOCIATED WITH A
BROAD SUBTROPICAL SHORTWAVE TROUGH. TC WASI IS FORECAST TO
TRANSITION TO A SUBTROPICAL CYCLONE BY TAU 48, BUT MAY DISSIPATE
PRIOR TO COMPLETING SUBTROPICAL TRANSITION. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 230600Z IS 12 FEET. NEXT WARNINGS AT 231500Z, 232100Z,
240300Z AND 240900Z.//
NNNN

>

2020-02-23 02:53

WTPS32 PGTW 230300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 007//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 007
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   230000Z --- NEAR 16.2S 171.4W
     MOVEMENT PAST SIX HOURS - 150 DEGREES AT 12 KTS
     POSITION ACCURATE TO WITHIN 030 NM
     POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
     SATELLITE AND EXTRAPOLATION
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   REPEAT POSIT: 16.2S 171.4W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   231200Z --- 18.1S 170.9W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 170 DEG/ 08 KTS
    ---
   24 HRS, VALID AT:
   240000Z --- 19.7S 170.6W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 175 DEG/ 07 KTS
    ---
   36 HRS, VALID AT:
   241200Z --- 21.1S 170.5W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING SUBTROPICAL
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 170 DEG/ 08 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   250000Z --- 22.6S 170.2W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   SUBTROPICAL
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            060 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
    ---
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

>

2020-02-22 20:54

WTPS32 PGTW 222100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 006//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 006
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   221800Z --- NEAR 15.1S 172.0W
     MOVEMENT PAST SIX HOURS - 160 DEGREES AT 06 KTS
     POSITION ACCURATE TO WITHIN 040 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 - 050 NM NORTHEAST QUADRANT
                            045 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   REPEAT POSIT: 15.1S 172.0W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   230600Z --- 16.7S 171.0W
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT
                            000 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            055 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 170 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   231800Z --- 18.5S 170.6W
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 170 DEG/ 09 KTS
    ---
   36 HRS, VALID AT:
   240600Z --- 20.3S 170.3W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 165 DEG/ 08 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   241800Z --- 21.9S 169.9W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING SUBTROPICAL
   RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 160 DEG/ 08 KTS
    ---
   72 HRS, VALID AT:
   251800Z --- 24.8S 168.8W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   SUBTROPICAL
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            050 NM SOUTHEAST QUADRANT
                            015 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
    ---
REMARKS:
222100Z POSITION NEAR 15.5S 171.7W.
22FEB20. TROPICAL CYCLONE (TC) 18P (WASI), LOCATED APPROXIMATELY 89
NM WEST-SOUTHWEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED SOUTH-
SOUTHEASTWARD AT 06 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY INDICATES THAT THE MAJORITY OF THE
DEEP CONVECTION AND BANDING IS LOCATED OVER THE EASTERN SEMICIRCLE OF
THE SYSTEM. A 221812Z SSMIS 37 GHZ MICROWAVE IMAGE DEPICTS DEEP
CONVECTION TO THE EAST WRAPPING INTO A LOW-LEVEL CIRCULATION CENTER,
LENDING GOOD CONFIDENCE TO THE INITIAL POSITION. THE INITIAL
INTENSITY IS SET AT 45 KTS, HEDGED BETWEEN A PGTW DVORAK INTENSITY
ESTIMATE OF T2.5/3.5 (35/55 KTS) AND DVORAK CURRENT INTENSITY
ESTIMATES OF T3.0 (45 KTS) BY NFFN AND T2.5 (35 KTS) BY KNES AND
PHFO. TRACKING ALONG THE SOUTHWESTERN PERIPHERY OF A SUBTROPICAL
RIDGE (STR), TC 18P IS MOVING SOUTH-SOUTHEASTWARD AND IS EXPECTED TO
GRADUALLY SHIFT TO A SOUTHWARD TRACK AS THE STR RE-ORIENTS. IN THE
NEAR TERM, LOW VERTICAL WIND SHEAR (VWS), GOOD POLEWARD AND FAIR
EQUATORWARD OUTFLOW, AND WARM (28-29 CELSIUS) SEA SURFACE
TEMPERATURES (SST) WILL ALLOW FOR A BRIEF PERIOD OF RE-
INTENSIFICATION TO A PEAK OF 50 KTS. AFTER THIS, INCREASING VWS AND
COOLING SST WILL CAUSE TC 18P TO STEADILY WEAKEN. AROUND TAU 48, TC
18P WILL BEGIN TO INTERACT WITH THE STRONG SUBTROPICAL WESTERLY FLOW
AND ENCOUNTER HIGHER VWS, TRANSITIONING INTO A SUBTROPICAL CYCLONE BY
TAU 72. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH TWO
OUTLIERS, GFS TO THE EAST AND THE UKMET ENSEMBLE TO THE WEST.
HOWEVER, THE JTWC FORECAST TRACK IS LAID NEAR THE MAJORITY OF THE
MODEL SOLUTIONS AND THE MULTI-MODEL CONSENSUS, PLACING GOOD
CONFIDENCE IN THE FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
221800Z IS 15 FEET. NEXT WARNINGS AT 230300Z, 230900Z, 231500Z AND
232100Z.//

>

2020-02-22 14:47

WTPS32 PGTW 221500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 005//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 005
   02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   221200Z --- NEAR 14.5S 172.2W
     MOVEMENT PAST SIX HOURS - 135 DEGREES AT 07 KTS
     POSITION ACCURATE TO WITHIN 030 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 - 035 NM NORTHEAST QUADRANT
                            045 NM SOUTHEAST QUADRANT
                            035 NM SOUTHWEST QUADRANT
                            040 NM NORTHWEST QUADRANT
   REPEAT POSIT: 14.5S 172.2W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   230000Z --- 15.8S 171.2W
   MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 165 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   231200Z --- 17.5S 170.7W
   MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 045 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            045 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 165 DEG/ 09 KTS
    ---
   36 HRS, VALID AT:
   240000Z --- 19.2S 170.3W
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 175 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   241200Z --- 20.9S 170.1W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING SUBTROPICAL
   RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            010 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 170 DEG/ 09 KTS
    ---
   72 HRS, VALID AT:
   251200Z --- 24.3S 169.6W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   SUBTROPICAL
   RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
    ---
REMARKS:
221500Z POSITION NEAR 14.8S 171.9W.
22FEB20. TROPICAL CYCLONE (TC) 18P (WASI), LOCATED APPROXIMATELY 88
NM WEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED SOUTHEASTWARD AT
07 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY CONTINUES TO INDICATE A SLIGHT WEAKENING OF DEEP
CONVECTIVE STRUCTURE DUE TO INCREASED FRICTIONAL EFFECTS WITH
WESTERN SAMOA. HOWEVER, A 221321Z GMI 89GHZ IMAGE DEPICTS SHALLOW
BANDING WRAPPING INTO A DEFINED LOW-LEVEL CIRCULATION CENTER WITH
FRAGMENTED DEEP CONVECTIVE BANDING OVER THE EASTERN SEMICIRCLE.
SURFACE OBSERVATIONS FROM PAGO PAGO (NSTU), WITHIN THE DEEP
CONVECTIVE BANDS, INDICATE SUSTAINED SURFACE WINDS OF 15 TO 20 KNOTS
WITH GUSTS AS HIGH AS 37 KNOTS. THE INITIAL INTENSITY IS ASSESSED AT
45 KNOTS BASED ON A PGTW DVORAK INTENSITY ESTIMATE OF T2.5/3.5
(35/55 KNOTS). TC 18P IS TRACKING SOUTHEASTWARD ALONG THE
SOUTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) AND IS EXPECTED
TO GRADUALLY TURN SOUTHWARD AS THE STR RE-ORIENTS. NUMERICAL MODEL
GUIDANCE AS WELL AS THE ECMWF ENSEMBLE GUIDANCE SUPPORT THIS TRACK
SCENARIO WITH GOOD CONFIDENCE. TC 18P IS FORECAST TO RE-INTENSIFY TO
A PEAK OF 60 KNOTS BY TAU 24 AS IT TRACKS AWAY FROM WESTERN SAMOA
DUE TO FAVORABLE POLEWARD OUTFLOW, LOW VERTICAL WIND SHEAR (VWS) AND
WARM SST (28-29C) VALUES. AFTER TAU 24, ENVIRONMENTAL CONDITIONS
WILL GRADUALLY DEGRADE WITH INCREASING VWS AND COOLER SST, WHICH
WILL SERVE TO WEAKEN THE SYSTEM. BY TAU 48, TC WASI WILL ENCOUNTER
HIGH VWS ASSOCIATED WITH STRONG SUBTROPICAL WESTERLY FLOW,
THEREFORE, THE SYSTEM IS EXPECTED TO TRANSITION TO A SUBTROPICAL
CYCLONE BY TAU 72. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 221200Z IS 18
FEET. NEXT WARNINGS AT 222100Z, 230300Z, 230900Z AND 231500Z.
REFER TO TROPICAL CYCLONE 17P (VICKY) FINAL WARNING (WTPS31 PGTW).//

>

2020-02-22 08:27

WTPS32 PGTW 220900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (WASI) WARNING NR 004//
RMKS/
1. TROPICAL CYCLONE 18P (WASI) WARNING NR 004
   02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   220600Z --- NEAR 14.0S 172.7W
     MOVEMENT PAST SIX HOURS - 130 DEGREES AT 10 KTS
     POSITION ACCURATE TO WITHIN 030 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
                            025 NM SOUTHEAST QUADRANT
                            025 NM SOUTHWEST QUADRANT
                            025 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            035 NM SOUTHWEST QUADRANT
                            035 NM NORTHWEST QUADRANT
   REPEAT POSIT: 14.0S 172.7W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   221800Z --- 15.2S 171.5W
   MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            010 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 155 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   230600Z --- 16.8S 170.7W
   MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 170 DEG/ 09 KTS
    ---
   36 HRS, VALID AT:
   231800Z --- 18.6S 170.4W
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            050 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 170 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   240600Z --- 20.3S 170.1W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING SUBTROPICAL
   RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 170 DEG/ 09 KTS
    ---
   72 HRS, VALID AT:
   250600Z --- 23.7S 169.6W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   SUBTROPICAL
   RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            040 NM NORTHWEST QUADRANT
    ---
REMARKS:
220900Z POSITION NEAR 14.3S 172.4W.
22FEB20. TROPICAL CYCLONE (TC) 18P (WASI), LOCATED APPROXIMATELY 118
NM WEST OF PAGO PAGO, AMERICAN SAMOA, HAS TRACKED SOUTHEASTWARD AT 10
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A SLIGHT WEAKENING OF DEEP CONVECTION DUE TO
INCREASED FRICTIONAL EFFECTS WITH WESTERN SAMOA. HOWEVER, A 220502Z
SSMIS COLOR COMPOSITE MICROWAVE IMAGE DEPICTS A MIDGET SYSTEM WITH A
WELL-DEFINED, SMALL MICROWAVE EYE FEATURE, WHICH, ALONG WITH A PGTW
DVORAK INTENSITY ESTIMATE OF T3.5 (55 KNOTS), SUPPORTS THE CURRENT
INTENSITY OF 55 KNOTS. THE SSMIS IMAGE ALSO PROVIDES GOOD CONFIDENCE
IN THE CURRENT POSITION. TC 18P IS TRACKING SOUTHEASTWARD ALONG THE
SOUTHWESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) AND IS EXPECTED
TO GRADUALLY TURN SOUTHWARD AS THE STR RE-ORIENTS. NUMERICAL MODEL
GUIDANCE AS WELL AS THE ECMWF ENSEMBLE GUIDANCE SUPPORT THIS TRACK
SCENARIO WITH GOOD CONFIDENCE. TC 18P IS FORECAST TO INTENSIFY TO A
PEAK OF 65 KNOTS BY TAU 12 AS IT TRACKS AWAY FROM WESTERN SAMOA DUE
TO FAVORABLE OUTFLOW, LOW VERTICAL WIND SHEAR (VWS) AND WARM SST (28-
29C) VALUES. AFTER TAU 24, ENVIRONMENTAL CONDITIONS WILL GRADUALLY
DEGRADE WITH INCREASING VWS AND COOLER SST, WHICH WILL SERVE TO
WEAKEN THE SYSTEM. BY TAU 48, TC WASI WILL ENCOUNTER HIGH VWS
ASSOCIATED WITH STRONG SUBTROPICAL WESTERLY FLOW, THEREFORE, THE
SYSTEM IS EXPECTED TO TRANSITION TO A SUBTROPICAL CYCLONE BY TAU 72.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 220600Z IS 18 FEET. NEXT WARNINGS
AT 221500Z, 222100Z, 230300Z AND 230900Z. REFER TO TROPICAL CYCLONE
17P (VICKY) FINAL WARNING (WTPS31 PGTW).//

>

2020-02-22 03:29

WTPS32 PGTW 220300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (EIGHTEEN) 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 IMAG
E 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. NEXTWARNINGS AT 221500Z AND 230300Z. REFER TO TROPICAL CYCLONE
17P (VICKY) WARNINGS (WTPS31 PGTW) FOR SIX-HOURLY UPDATES.//

>

2020-02-21 20:13

WTPS32 PGTW 212100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (EIGHTEEN) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 18P (EIGHTEEN) WARNING NR 002
   02 ACTIVE TROPICAL CYCLONES IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   211800Z --- NEAR 13.2S 174.3W
     MOVEMENT PAST SIX HOURS - 120 DEGREES AT 10 KTS
     POSITION ACCURATE TO WITHIN 060 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   REPEAT POSIT: 13.2S 174.3W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   220600Z --- 14.1S 172.7W
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 140 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   221800Z --- 15.4S 171.5W
   MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 165 DEG/ 12 KTS
    ---
   36 HRS, VALID AT:
   230600Z --- 17.6S 170.8W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 180 DEG/ 08 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   231800Z --- 19.3S 170.8W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            010 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 190 DEG/ 07 KTS
    ---
   72 HRS, VALID AT:
   241800Z --- 21.9S 171.3W
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
212100Z POSITION NEAR 13.4S 173.9W.
21FEB20. TROPICAL CYCLONE 18P (EIGHTEEN), LOCATED APPROXIMATELY
220 NM WEST-NORTHWEST OF PAGO PAGO, HAS TRACKED EAST-
SOUTHEASTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED
INFRARED (EIR) SATELLITE IMAGERY DEPICTS DISORGANIZED FLARING
CONVECTION OBSCURING A LOW-LEVEL CIRCULATION CENTER (LLCC). THE
INITIAL POSITION IS PLACED WITH FAIR CONFIDENCE BASED ON A 211625Z
SSMIS 91GHZ MICROWAVE IMAGE. THE INITIAL INTENSITY CONTINUES TO BE
ASSESSED AT 30 KNOTS, WHICH IS CORROBORATED BY DVORAK INTENSITY
ESTIMATES OF T2.0 FROM PGTW AND T1.5 FROM KNES. VERTICAL WIND SHEAR
REMAINS LOW (5-10 KNOTS) WITH FAIR OUTFLOW AND WARM
(28-29 CELSIUS) SEA SURFACE TEMPERATURES. HOWEVER, INTENSIFICATION
HAS BEEN SLOW, WITH ONLY A GRADUAL INTENSIFICATION RATE EXPECTED
THROUGH THE FORECAST PERIOD AS VERTICAL WIND SHEAR GRADUALLY
INCREASES THROUGH TAU 72. THE PEAK INTENSITY FORECAST HAS
SUBSEQUENTLY BEEN REDUCED BY 5 KNOTS. 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 DISSIPATE BY 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 211800Z IS 15 FEET. NEXT
WARNINGS AT 220300Z, 220900Z, 221500Z AND 222100Z.
REFER TO TROPICAL CYCLONE 17P (VICKY) WARNINGS (WTPS31 PGTW)
FOR SIX-HOURLY UPDATES.
//
NNNN

>

2020-02-21 13:54

WTPS32 PGTW 211500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 18P (EIGHTEEN) WARNING NR 001//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/210221ZFEB2020//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
1. TROPICAL CYCLONE 18P (EIGHTEEN) 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:
   211200Z --- NEAR 12.7S 175.2W
     MOVEMENT PAST SIX HOURS - 115 DEGREES AT 07 KTS
     POSITION ACCURATE TO WITHIN 045 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   REPEAT POSIT: 12.7S 175.2W
    ---
   FORECASTS:
   12 HRS, VALID AT:
   220000Z --- 13.4S 173.7W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 125 DEG/ 09 KTS
    ---
   24 HRS, VALID AT:
   221200Z --- 14.4S 172.2W
   MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 155 DEG/ 10 KTS
    ---
   36 HRS, VALID AT:
   230000Z --- 16.1S 171.3W
   MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            000 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 170 DEG/ 09 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   231200Z --- 17.9S 171.0W
   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 - 030 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            010 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 180 DEG/ 06 KTS
    ---
   72 HRS, VALID AT:
   241200Z --- 20.4S 171.1W
   MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
    ---
REMARKS:
211500Z POSITION NEAR 12.9S 174.8W.
21FEB20. TROPICAL CYCLONE (TC) 18P (EIGHTEEN), LOCATED APPROXIMATELY
280 NM WEST-NORTHWEST OF PAGO PAGO, HAS TRACKED EAST-SOUTHEASTWARD
AT 07 KNOTS (KTS) OVER THE PAST SIX HOURS. ANIMATED ENHANCED
INFRARED (EIR) SATELLITE IMAGERY REVEALS AN IMPROVED CYCLONIC
CIRCULATION ON THE SOUTHERN END OF A LINE OF DEEP CONVECTION THAT
EXTENDS NORTH-TO-SOUTH. BASED ON THE EIR, THERE IS FAIR CONFIDENCE
IN THE INITIAL POSITION. THE 30 KT INITIAL INTENSITY IS ON THE HIGH
END OF DVORAK INTENSITY ESTIMATES FROM T1.5-T2.0 (25-30 KTS).
ALTHOUGH THE INTENSITY IS BELOW THE BASIN WARNING THRESHOLD, THE
WARNING IS BEING GENERATED BECAUSE 18P IS EXPECTED TO INTENSIFY TO
45 KTS AS IT PASSES NEAR AMERICAN SAMOA AROUND TAU 24. WITH FAIR
POLEWARD OUTFLOW, LOW (5-10 KTS) VERTICAL WIND SHEAR (VWS), AND WARM
(28-29 CELSIUS) SEA SURFACE TEMPERATURES, THE ENVIRONMENT IS
FAVORABLE FOR INTENSIFICATION. TC 18P IS TRACKING ALONG THE SOUTHERN
PERIPHERY OF A NEAR EQUATORIAL RIDGE, FOLLOWING THE MONSOON TROUGH.
BY TAU 24, A SUBTROPICAL RIDGE TO THE EAST WILL SHIFT THE TRACK
POLEWARD. THE FAVORABLE ENVIRONMENT SHOULD ALLOW TC 18P TO PEAK AT
APPROXIMATELY 45 KTS BY TAU 24. WITH HIGH VWS EXPECTED AFTER TAU 48,
TC 18P SHOULD DISSIPATE BY TAU 72. THE TRACK AND INTENSITY FORECAST
ARE VERY SIMILAR TO WHAT WAS SEEN WITH 17P. NUMERICAL MODEL GUIDANCE
IS IN GOOD OVERALL AGREEMENT WITH THE JTWC TRACK FORECAST. WITH GOOD
AGREEMENT IN THE MODELS AND THE PRECEDENT SEEN WITH 17P, THERE IS
GOOD CONFIDENCE IN THE JTWC TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 211200Z IS 12 FEET. NEXT WARNINGS AT 212100Z, 220300Z,
220900Z AND 221500Z. REFER TO TROPICAL CYCLONE 17P (VICKY) WARNINGS
(WTPS31 PGTW) FOR SIX-HOURLY UPDATES.
2. THIS CANCELS AND SUPERSEDES REF A (WTPS21 PGTW 210230).//

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