WPAC: KROVANH - Post-Tropical

[Nancy Smar]

99W.INVEST

99W INVEST 201217 1200 6.0N 129.0E WPAC 15 1003

[Hayabusa]

And where is 98W? Why did they skip it?

[Nancy Smar]

And where is 98W? Why did they skip it?

In fact, they didn't skip 98W but looks like there is something wrong with it.
98W INVEST 201212 0600 14.0N 170.0W WPAC 15 0

[Hayabusa]

TD
Issued at 13:20 UTC, 18 December 2020

<Analysis at 12 UTC, 18 December>
Scale -
Intensity -
TD
Center position N8°20' (8.3°)
E124°10' (124.2°)
Direction and speed of movement W 25 km/h (14 kt)
Central pressure 1004 hPa
Maximum sustained wind speed 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)

<Forecast for 00 UTC, 19 December>
Intensity -
TD
Center position of probability circle N8°55' (8.9°)
E121°00' (121.0°)
Direction and speed of movement W 30 km/h (16 kt)
Central pressure 1002 hPa
Maximum wind speed near center 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)
Radius of probability circle 110 km (60 NM)

<Forecast for 12 UTC, 19 December>
Intensity -
Center position of probability circle N9°40' (9.7°)
E119°20' (119.3°)
Direction and speed of movement WNW 15 km/h (9 kt)
Central pressure 1000 hPa
Maximum wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 150 km (80 NM)

<Forecast for 12 UTC, 20 December>
Intensity -
Center position of probability circle N10°05' (10.1°)
E114°50' (114.8°)
Direction and speed of movement W 20 km/h (11 kt)
Central pressure 998 hPa
Maximum wind speed near center 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 240 km (130 NM)

<Forecast for 12 UTC, 21 December>
Intensity -
Center position of probability circle N8°30' (8.5°)
E112°00' (112.0°)
Direction and speed of movement WSW 15 km/h (8 kt)
Central pressure 994 hPa
Maximum wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
Radius of probability circle 370 km (200 NM)

<Forecast for 12 UTC, 22 December>
Intensity -
Center position of probability circle N7°20' (7.3°)
E109°25' (109.4°)
Direction and speed of movement WSW 15 km/h (7 kt)
Central pressure 998 hPa
Maximum wind speed near center 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 520 km (280 NM)

<Forecast for 12 UTC, 23 December>
Intensity -
Center position of probability circle N7°30' (7.5°)
E105°40' (105.7°)
Direction and speed of movement W 15 km/h (9 kt)
Central pressure 1000 hPa
Maximum wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 700 km (390 NM)

[doomhaMwx]

JMA has upgraded to TS "Krovanh" but will be short-lived.

TS 2023 (Krovanh)
Issued at 07:05 UTC, 20 December 2020

<Analysis at 06 UTC, 20 December>
Scale -
Intensity -
Center position N10°25' (10.4°)
E114°50' (114.8°)
Direction and speed of movement W 25 km/h (14 kt)
Central pressure 1000 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area NW 220 km (120 NM)
SE 110 km (60 NM)

<Forecast for 18 UTC, 20 December>
Intensity -
Center position of probability circle N9°40' (9.7°)
E113°00' (113.0°)
Direction and speed of movement WSW 20 km/h (10 kt)
Central pressure 998 hPa
Maximum sustained wind speed 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 75 km (40 NM)

<Forecast for 06 UTC, 21 December>
Intensity -
Center position of probability circle N8°55' (8.9°)
E112°00' (112.0°)
Direction and speed of movement SW 10 km/h (6 kt)
Central pressure 998 hPa
Maximum sustained wind speed 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 95 km (50 NM)

<Forecast for 06 UTC, 22 December>
Intensity -
Center position of probability circle N8°35' (8.6°)
E109°55' (109.9°)
Direction and speed of movement W Slow
Central pressure 1000 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 165 km (90 NM)

<Forecast for 06 UTC, 23 December>
Intensity -
TD
Center position of probability circle N8°30' (8.5°)
E106°35' (106.6°)
Direction and speed of movement W 15 km/h (8 kt)
Central pressure 1004 hPa
Radius of probability circle 260 km (140 NM)

WDPN31 PGTW 200900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 26W (KROVANH)
WARNING NR 002//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 26W (TWENTYSIX), LOCATED APPROXIMATELY 485 NM
EAST OF HO CHI MINH CITY, VIETNAM, HAS TRACKED WEST-NORTHWESTWARD AT
10 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) DEPICTS A HIGHLY SHEARED, ASYMMETRIC, AND DISORGANIZED
SYSTEM, WITH MULTIPLE EXPOSED, LOW LEVEL VORTICES WRAPPING AROUND
THE BROADER CIRCULATION CENTER AND LIMITED FLARING CONVECTION
DISPLACED NORTH AND WEST OF THE LOW-LEVEL CIRCULATION CENTER (LLCC).
DUE TO THE PRESENCE OF MULTIPLE VORTICES, THE INITIAL POSITION IS
PLACED WITH LOW CONFIDENCE IN THE ROUGH CENTROID OF THE LARGER
CIRCULATION, CONSISTENT WITH RECENT AGENCY FIX POSITIONS FROM PGTW
AND RJTD. THE INITIAL INTENSITY IS ASSESSED AT 30 KNOTS WITH LOW
CONFIDENCE, HEDGED ABOVE THE SUBJECTIVE DVORAK INTENSITY ESTIMATES
OF T1.0 (25 KNOTS) FROM PGTW AND T1.5 (25 KNOTS) FROM RJTD IN
RECOGNITION OF HIGHER WINDS, PART OF PRE-EXISTING NORTHEAST SURGE
FLOW, PRESENT TO THE NORTH AND WEST OF THE CIRCULATION. CONVERGENT
LOW LEVEL FLOW BETWEEN THE NORTHEAST SURGE FLOW AND THE APPROACHING
LLCC IS SUPPORTING THE GENERATION OF DEEP, FLARING CONVECTION TO THE
NORTHWEST OF THE CIRCULATION. ENVIRONMENTAL CONDITIONS ARE
MARGINALLY FAVORABLE FOR DEVELOPMENT, WITH MODERATE TO HIGH (20-25
KTS) VERTICAL WIND SHEAR (VWS), VERY WARM SEA SURFACE TEMPERATURES
(28-29C), AND STRONG DIVERGENT, POLEWARD OUTFLOW ALOFT. WHILE THE
OVERALL ENVIRONMENT IS SUPPORTIVE OF ADDITIONAL DEVELOPMENT, THE
HIGH VWS IS CURRENTLY INHIBITING THE CONSOLIDATION OF THE CORE, AS
REFLECTED BY THE SHEARED NATURE OF THE CONVECTION. THE SYSTEM IS
TRACKING GENERALLY WESTWARD FOLLOWING THE FLOW ASSOCIATED WITH A LOW
TO MID-LAYER STEERING RIDGE TO THE NORTH.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TD 26W IS EXPECTED TO CONTINUE TRACKING GENERALLY WEST-
SOUTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF THE STEERING RIDGE
ENTRENCHED TO THE NORTH THROUGH TAU 48. SLOW INTENSIFICATION IS
FORECAST THROUGH TAU 24 AS THE SYSTEM AS THE WINDS ASSOCIATED WITH
THE NORTHEAST SURGE FLOW BEGIN TO WRAP AROUND THE SOUTHERN SIDE OF
THE LLCC AND ROBUST DIVERGENT OUTFLOW ALOFT OFFSETS MODERATE VWS. A
SLIGHT REORIENTATION OF THE UPPER-LEVEL FLOW PATTERN WILL LEAD TO
MORE CONVERGENT OUTFLOW ALOFT, COMBINED WITH PERSISTENT MODERATE
VWS, DECREASING SSTS, AND A SEPARATION FROM THE NORTHEAST SURGE
FLOW, WILL LEAD TO A WEAKENING TREND FROM TAU 36 THROUGH THE
REMAINDER OF THE FORECAST PERIOD. AS THE SYSTEM BEGINS TO WEAKEN, IT
WILL ALSO SHIFT TO A MORE WESTWARD TRACK AS IT COMES UNDER THE
STEERING INFLUENCE OF THE LOWER-LEVEL FLOW. NUMERICAL MODEL GUIDANCE
IS IN GOOD AGREEMENT WITH THE OVERALL TRACK FORECAST SCENARIO, WITH
SMALL SPREAD THROUGH TAU 48. BEYOND TAU 48, MODEL GUIDANCE SHOWS
INCREASING UNCERTAINTY, WITH THE NAVGEM, UKMET AND GFS ENSEMBLES
SHOWING A TRACK OVER FAR SOUTHERN VIETNAM, WHICH THE REMAINDER OF
TRACK GUIDANCE KEEPS THE CENTER OF CIRCULATION WELL OFFSHORE
SOUTHERN VIETNAM. OVERALL, IN LIGHT OF THE UNCERTAINTY IN THE
INITIAL POSITION, AND SUBSEQUENT UNCERTAINTY IN THE AMOUNT OF AND
TIMING OF THE INTERACTION WITH THE NORTHEAST SURGE FLOW, AND IMPACT
THAT ON THE TRACK, THERE IS OVERALL LOW CONFIDENCE IN THE JTWC
FORECAST THROUGH TAU 72.
C. TD 26W IS EXPECTED TO FULLY DISSIPATE BY TAU 96 AS IT
CONTINUES TRACKING WESTWARD AROUND THE SOUTHERN TIP OF VIETNAM INTO
THE SOUTHERN GULF OF THAILAND.//
NNNN

[NotoSans]

Downgraded to TD already. Perhaps shouldn’t be named in the first place.