WPAC: KUJIRA - Post-Tropical

[euro6208]

[euro6208]

Up to a TS.

WDPN31 PGTW 271500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (KUJIRI)
WARNING NR 004//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 15W (KUJIRA), LOCATED APPROXIMATELY 153 NM
EAST-SOUTHEAST OF MINAMI TORI SHIMA, HAS TRACKED NORTH-NORTHWESTWARD
AT 19 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS A PARTIALLY-EXPOSED LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH EXTENSIVE DEEP CONVECTIVE BANDING OVER THE
SOUTHERN AND EASTERN SEMICIRCLES. A 271055Z GMI 89GHZ MICROWAVE
IMAGE INDICATES IMPROVED CONVECTIVE BANDING WRAPPING INTO THE
NORTHERN QUADRANT OF THE SYSTEM. OVERALL, THERE IS FAIR CONFIDENCE
IN THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 35
KNOTS, HEDGED ABOVE DVORAK ESTIMATES OF T2.0 (30 KNOTS), BASED ON
RECENT ASCAT DATA AND A 271200Z ADT ESTIMATE OF T2.5 (35 KNOTS).
UPPER-LEVEL ANALYSIS CONTINUES TO REVEAL A MARGINALLY-FAVORABLE
ENVIRONMENT WITH A BROAD, CONVERGENT UPPER LOW POSITIONED OVER THE
CENTER, WHICH CONTINUES TO HAMPER DEVELOPMENT, OFFSET BY ROBUST
EQUATORWARD OUTFLOW AND DIFFLUENT POLEWARD OUTFLOW. SST VALUES (29-
30C) REMAIN CONDUCIVE FOR FURTHER DEVELOPMENT. TS 15W IS TRACKING
NORTHWESTWARD UNDER THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE
(STR) POSITIONED TO THE NORTHEAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 15W IS FORECAST TO TRACK NORTH-NORTHWESTWARD THROUGH TAU 24
WITH STEADY INTENSIFICATION. AFTER TAU 24, TS 15W WILL BEGIN TO
ROUND THE STR WITH FURTHER INTENSIFICATION DUE TO IMPROVING POLEWARD
OUTFLOW ASSOCIATED WITH A MAJOR SHORTWAVE TROUGH DIGGING SOUTH OF
JAPAN. THE SYSTEM IS EXPECTED TO PEAK AT 70 KNOTS BY TAU 36. TS 15W
IS FORECAST TO BEGIN EXTRA-TROPICAL TRANSITION (ETT) AS IT RECURVES
INTO THE MIDLATITUDE WESTERLIES NEAR TAU 48. AFTER TAU 48, TS 15W
WILL WEAKEN AS IT ENCOUNTERS INCREASING VERTICAL WIND SHEAR (25-30
KNOTS) AND TRACKS OVER COOL SST VALUES (23-20C). TS 15W WILL
COMPLETE ETT NEAR TAU 72 AS IT GAINS FRONTAL CHARACTERISTICS AND
BECOMES EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. NUMERICAL MODEL
GUIDANCE REMAINS IN TIGHT AGREEMENT THROUGH THE FORECAST PERIOD,
LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

45 knots and still forecast to become a typhoon.


WDPN31 PGTW 280900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (KUJIRA) WARNING NR
007//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 15W (KUJIRA), LOCATED APPROXIMATELY 232 NM
NORTH OF MINAMI TORI SHIMA, HAS TRACKED NORTH-NORTHWESTWARD AT 16
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A PARTIALLY-EXPOSED, WELL-DEFINED LOW-LEVEL
CIRCULATION CENTER (LLCC) WITH PERSISTENT DEEP CONVECTION OVER THE
WESTERN SEMICIRCLE. A 280622Z SSMIS 37GHZ MICROWAVE IMAGE REVEALS
SHALLOW BANDING WRAPPING TIGHTLY INTO A DEFINED LLCC, WHICH SUPPORTS
THE INITIAL POSITION WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS
ASSESSED AT 45 KNOTS BASED ON A PGTW DVORAK ESTIMATE OF T3.0 (45
KNOTS) AND RECENT ASCAT DATA. UPPER-LEVEL ANALYSIS INDICATES A
MARGINALLY-FAVORABLE ENVIRONMENT WITH ROBUST POLEWARD OUTFLOW, WARM
SST (29-30C) AND LOW VERTICAL WIND SHEAR (VWS). HOWEVER, STRONG
CONVERGENCE OVER THE SOUTHERN SEMICIRCLE CONTINUES TO HINDER
CONVECTIVE DEVELOPMENT. TS 15W IS TRACKING NORTH-NORTHWESTWARD UNDER
THE STEERING INFLUENCE OF A SUBTROPICAL RIDGE (STR) POSITIONED TO
THE NORTHEAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 15W IS FORECAST TO TRACK NORTHWARD TO NORTH-NORTHEASTWARD
THROUGH TAU 24 AS IT ROUNDS THE SUBTROPICAL RIDGE. AFTER TAU 24, TS
15W WILL TURN NORTHEASTWARD AND SHOULD BEGIN EXTRATROPICAL
TRANSITION (ETT) NEAR TAU 36 AS IT INTERACTS WITH MIDLATITUDE
WESTERLIES AND ENCOUNTERS INCREASING VWS (20-30 KNOTS). THE SYSTEM
IS FORECAST TO INTENSIFY TO A PEAK INTENSITY OF 65 KNOTS BY TAU 36.
GRADUAL WEAKENING IS EXPECTED AFTER TAU 36 AS VWS INCREASES TO 30-40
KNOTS AND THE SYSTEM TRACKS OVER COOL SST (24-20C). AS THE SYSTEM
RECURVES EAST-NORTHEASTWARD TO EASTWARD, IT WILL COMPLETE ETT
BETWEEN TAU 60 TO 72 AS IT GAINS FRONTAL CHARACTERISTICS AND BECOMES
EMBEDDED WITHIN THE MIDLATITUDE WESTERLIES. NUMERICAL MODEL GUIDANCE
AND THE ECMWF ENSEMBLE SOLUTIONS REMAIN IN TIGHT AGREEMENT
THROUGHOUT THE FORECAST PERIOD. THUS, THERE IS HIGH CONFIDENCE IN
THE JTWC FORECAST TRACK.//
NNNN

[Hayabusa]

Amazing that earlier the forecast peak was 950 mb now it's only 985

STS 2013 (Kujira)
Issued at 12:50 UTC, 28 September 2020

<Analysis at 12 UTC, 28 September>
Scale -
Intensity -
Center position N28°50' (28.8°)
E152°50' (152.8°)
Direction and speed of movement NNW 25 km/h (13 kt)
Central pressure 990 hPa
Maximum wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
≥ 30 kt wind area E 520 km (280 NM)
W 280 km (150 NM)
<Forecast for 00 UTC, 29 September>
Intensity -
Center position of probability circle N32°20' (32.3°)
E153°20' (153.3°)
Direction and speed of movement N 30 km/h (17 kt)
Central pressure 985 hPa
Maximum wind speed near center 30 m/s (55 kt)
Maximum wind gust speed 40 m/s (80 kt)
Radius of probability circle 75 km (40 NM)
Storm warning area E 185 km (100 NM)
W 130 km (70 NM)

[euro6208]

WDPN31 PGTW 290300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 15W (KUJIRA) WARNING NR
010//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 15W (KUJIRA), LOCATED APPROXIMATELY 734 NM EAST
OF YOKOSUKA, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 23 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS
STRONG POLEWARD OUTFLOW CONTINUED TO ENHANCE AND DEEPEN THE CENTRAL
CONVECTION THAT IS NOW VERY CLOSE TO FORMING AN EYE. THE INITIAL
POSITION AND INTENSITY ARE EXTRAPOLATED WITH HIGH CONFIDENCE FROM A
DEFINED CIRCULATION IN THE 282328Z ASCAT BULLSEYE PASS AND CLUSTERED
DVORAK FIXES OF T3.5/55KTS FROM PGTW AND T4.0/65KTS FROM RJTD. ANALYSIS
INDICATES A MARGINALLY-FAVORABLE ENVIRONMENT WITH ROBUST POLEWARD
OUTFLOW AND WARM SST (29-30C) THAT ARE PARTLY OFFSET BY LOW TO MODERATE
(10-20KT) VERTICAL WIND SHEAR (VWS). ALSO, STRONG CONVERGENCE OVER THE
SOUTHERN SEMICIRCLE ASSOCIATED WITH AN UPPER LEVEL TROUGH CONTINUES TO
TEMPER CONVECTIVE DEVELOPMENT. TS 15W IS TRACKING UNDER THE STEERING
INFLUENCE OF A SUBTROPICAL RIDGE (STR) TO THE EAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS KUJIRA WILL CONTINUE TO ACCELERATE NORTHEASTWARD ON THE
POLEWARD SIDE OF THE STR. THE MARGINALLY-FAVORABLE ENVIRONMENT WILL
PROMOTE FURTHER INTENSIFICATION TO A PEAK OF 65KTS BY TAU 12.
AFTERWARD, INCREASING VWS AND COOLING SSTS WILL GRADUALLY WEAKEN THE
SYSTEM TO 45KTS BY TAU 36. CONCURRENTLY BY TAU 12, TS 15W WILL BEGIN
EXTRATROPICAL TRANSITION AS IT ENTERS THE BAROCLINIC ZONE, BECOMING A
STORM-FORCE COLD CORE LOW BY TAU 24. NUMERICAL MODELS REMAIN IN TIGHT
AGREEMENT THROUGHOUT THE FORECAST PERIOD, LENDING HIGH CONFIDENCE IN
THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

Could already be a typhoon

[Hayabusa]

Minimal typhoon

15W KUJIRA 200929 0600 34.8N 155.1E WPAC 65 974

[euro6208]

TPPN11 PGTW 290608

A. TROPICAL STORM 15W (KUJIRA)

B. 29/0600Z

C. 34.82N

D. 155.03E

E. FIVE/HMWRI8

F. T4.0/4.0/D1.0/24HRS STT: D0.5/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 49A/PBO PTLY XPSD LLCC/ANMTN. CNVCTN WRAPS 1.10 ON
LOG10 SPIRAL YIELDING A DT OF 4.0. MET AND PT AGREE. DBO DT.

I. ADDITIONAL POSITIONS: NONE


HEINS

[euro6208]

TXPQ23 KNES 290311
TCSWNP

A. 15W (KUJIRA)

B. 29/0230Z

C. 33.5N

D. 154.4E

E. THREE/HIMAWARI-8

F. T4.0/4.0

G. IR/EIR/VIS/GMI

H. REMARKS...THIS INTENSITY ESTIMATE WAS DERIVED USING 4 KM IR
DATA. 12/10 BANDING RESULTS IN A DT OF 4.0. MET AND PT ARE UNAVAILABLE
AS THE STORM WAS CONSIDERED SUBTROPICAL 24 HOURS AGO. FT IS BASED ON DT.

I. ADDL POSITIONS

29/0100Z 33.0N 154.2E GMI


...CLARK

[euro6208]

I would have went higher considering ADT is at 76 knots.

[euro6208]

WDPN31 PGTW 290900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 15W (KUJIRA) WARNING NR
011//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 15W (KUJIRA), LOCATED APPROXIMATELY 756 NM EAST
OF YOKOSUKA, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT 24 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE (MSI)
IMAGERY DEPICTS DENSE, PERSISTENT CONVECTION WRAPPING INTO AN
OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL
POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE LOW LEVEL
FEATURES PRESENT IN A TIMELY 290610Z SSMIS 37 GHZ IMAGE. THE
INITIAL INTENSITY IS PLACED WITH HIGH CONFIDENCE BASED ON
MULTIAGENCY DVORAK CURRENT INTENSITY ESTIMATES OF T4.0 (65 KTS,
PGTW AND RJTD). TY KUJIRA IS TRACKING ALONG THE NOTRTHWESTERN
PERIPHERY OF THE SUBTROPICAL RIDGE POSITIONED TO THE SOUTHEAST
AND THROUGH A MARGINAL ENVIRONMENT WITH WARM (27-28 CELSIUS) SEA
SURFACE TEMPERATURES OFFSET BY MODERATE (20-25 KTS) VERTICAL WIND
SHEAR (VWS) AND CONVERGENT FLOW ALOFT ALONG THE WESTERN PERIPHERY
OF THE SYSTEM.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY KUJIRA WILL CONTINUE TO ACCELERATE NORTHEASTWARD ALONG
THE PERIPHERY OF THE STR THROUGH THE REMAINDER OF THE FORECAST PERIOD.
ROBUST POLEWARD OUTFLOW AND CONTINUED WARM SST WILL OFFSET INCREASING
VWS AND ALLOW THE SYSTEM TO MAINTAIN 65 KTS INTENSITY THROUGH TAU 12.
BY THIS TIME THE SYSTEM WILL BEGIN EXTRATROPICAL TRANSITION (ETT) AS IT
APPROACHES THE BAROCLINIC ZONE. THEREAFTER, COOLER (22-24 CELSIUS) SST
WILL LEAD TO A GRADUAL WEAKENING TO 50 KTS BY TAU 24 AT WHICH POINT IT
WILL COMPLETE EXTRATROPICAL TRANSITION. THE SYSTEM WILL REMAIN AS A
SIGNIFICANT COLD CORE LOW WITH 40 KTS WINDS AT TAU 36. NUMERICAL MODELS
REMAIN IN TIGHT AGREEMENT WITH A MAXIMUM 115 NM SPREAD IN ACROSS TRACK
SOLUTIONS, LENDING HIGH CONFIDENCE IN THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

Eye see you.

[euro6208]

[Hayabusa]

Do we even have an active mod for the WPAC?

[euro6208]

CURRENT ESTIMATE
Date (mmddhhmm): 09290721
SATCON: MSLP = 966 hPa MSW = 77 knots
SATCON Member Consensus: 76.0 knots
Pressure -> Wind Using SATCON MSLP: 78 knots
Distance to Outer Closed Isobar Used is 175 nm
Eye Size Correction Used is 0 knots Source: NA

[euro6208]

[euro6208]

Continues to intensify.

[euro6208]

SATCON up to 79 knots.

May be 15 knots too low.

[Ed_2001]

SATCON up to 79 knots.

May be 15 knots too low.

Looks underestimated for sure especially by JMA which still pegs it at a High End (S)TS. Looks like a borderline Cat 2 on Satellite.

[euro6208]

WTPN31 PGTW 292100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL STORM 15W (KUJIRA) WARNING NR 013//
RMKS/
1. TROPICAL STORM 15W (KUJIRA) WARNING NR 013
DOWNGRADED FROM TYPHOON 15W
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
291800Z --- NEAR 38.0N 158.2E
MOVEMENT PAST SIX HOURS - 045 DEGREES AT 21 KTS
POSITION ACCURATE TO WITHIN 020 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
BECOMING EXTRATROPICAL
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT
150 NM SOUTHEAST QUADRANT
090 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
REPEAT POSIT: 38.0N 158.2E
---
FORECASTS:
12 HRS, VALID AT:
300600Z --- 40.5N 162.9E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
100 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 075 DEG/ 24 KTS
---
24 HRS, VALID AT:
301800Z --- 41.7N 169.1E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
---
REMARKS:
292100Z POSITION NEAR 38.6N 159.4E.
29SEP20. TROPICAL STORM 15W (KUJIRA), LOCATED APPROXIMATELY 802
NM EAST OF MISAWA, JAPAN, HAS TRACKED NORTHEASTWARD AT 21 KNOTS
OVER THE PAST SIX HOURS. 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 291800Z IS 23 FEET.//
NNNN