WTPS31 PGTW 182100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 05P (YASA) WARNING NR 026//
RMKS/
1. TROPICAL CYCLONE 05P (YASA) WARNING NR 026
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
181800Z --- NEAR 20.3S 178.0W
MOVEMENT PAST SIX HOURS - 180 DEGREES AT 08 KTS
POSITION ACCURATE TO WITHIN 030 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 150 NM NORTHEAST QUADRANT
170 NM SOUTHEAST QUADRANT
145 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
REPEAT POSIT: 20.3S 178.0W
---
FORECASTS:
12 HRS, VALID AT:
190600Z --- 21.5S 178.0W
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING SUBTROPICAL
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
150 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 195 DEG/ 06 KTS
---
24 HRS, VALID AT:
191800Z --- 22.7S 178.4W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING SUBTROPICAL
RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 210 DEG/ 06 KTS
---
36 HRS, VALID AT:
200600Z --- 23.7S 179.0W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING SUBTROPICAL
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
010 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 210 DEG/ 06 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
201800Z --- 24.7S 179.7W
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
130 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
---
REMARKS:
182100Z POSITION NEAR 20.6S 178.0W.
18DEC20. TROPICAL CYCLONE (TC) 05P (YASA), LOCATED APPROXIMATELY 243
NM EAST-SOUTHEAST OF SUVA, FIJI, HAS TRACKED SOUTHWARD AT 08
KNOTS OVER THE PAST SIX HOURS. TC 05P HAS CONTINUED TO INTERACT WITH
A BROAD UPPER-LEVEL TROUGH WITH STRONG (25 KNOTS) VERTICAL WIND
SHEAR (VWS), WHICH HAS CONTRIBUTED TO THE STEADY WEAKENING. ANIMATED
ENHANCED INFRARED SATELLITE IMAGERY DEPICTS AN OBLONG AREA OF DEEP
CONVECTION OBSCURING THE LOW-LEVEL CIRCULATION CENTER (LLCC) WITH
WARMING CLOUD TOPS. AN 181845Z SSMIS 37V GHZ MICROWAVE IMAGE
INDICATES A WELL-DEFINED LLCC WITH TIGHTLY-CURVED SHALLOW BANDING
OVER THE NORTHERN SEMICIRCLE AND LIMITED DEEP CONVECTIVE BANDING
OVER THE SOUTH QUADRANT. THIS IMAGE SUPPORTS THE INITIAL POSITION
WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS ASSESSED AT 60 KNOTS
BASED ON THE LOWER END OF DVORAK CURRENT INTENSITY ESTIMATES RANGING
FROM 3.5 TO 4.5 (55-77 KNOTS) AND AN ADT ESTIMATE OF 3.8 (60-65
KNOTS). TC 05P WILL TRACK SOUTHWARD TO SOUTH-SOUTHWESTWARD ALONG THE
PERIPHERY OF THE SUBTROPICAL RIDGE TO THE NORTHEAST BUT WILL REMAIN
EMBEDDED WITHIN THE DEEP UPPER-LEVEL TROUGH WITH INCREASING VWS (40-
60 KNOTS) AND COOLING SST VALUES (25C) AFTER TAU 18. TC 05P WILL
BEGIN SUBTROPICAL TRANSITION NEAR TAU 12 AS IT APPROACHES THE
SUBTROPICAL JET AND IS FORECAST TO COMPLETE SUBTROPICAL
TRANSITION BY TAU 48 AS IT TRACKS UNDER THE AFOREMENTIONED JET AND
THE WIND FIELD EXPANDS AND BECOMES HIGHLY ASYMMETRIC. STEADY
WEAKENING IS ANTICIPATED, HOWEVER, THE SYSTEM WILL REMAIN A STRONG
COLD-CORE LOW WITH 45-50 KNOT WINDS NEAR TAU 48. NUMERICAL MODEL
GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGH TAU 24. AFTER TAU 24,
NUMERICAL MODEL GUIDANCE DIVERGES WITH INCREASING UNCERTAINTY IN THE
JTWC FORECAST TRACK DUE TO THE COMPLEX TRANSITION AND MERGER WITH
THE UPPER-LEVEL TROUGH / LOW. THEREFORE, THERE IS MODERATE OVERALL
CONFIDENCE IN THE JTWC FORECAST TRACK. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 181800Z IS 22 FEET. NEXT WARNINGS AT 190300Z, 190900Z,
191500Z AND 192100Z.//
NNNN
--- SBBSecho 3.11-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (21:1/175)