WPAC: GAEMI - Post-Tropical

[doomhaMwx]

TS 1806 (Gaemi)
Issued at 03:50 UTC, 15 June 2018

<Analysis at 03 UTC, 15 June>
Scale -
Intensity -
Center position N22°35' (22.6°)
E121°20' (121.3°)
Direction and speed of movement E Slow
Central pressure 992 hPa
Maximum wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area SE 280 km (150 NM)
NW 170 km (90 NM)

[NotoSans]

Looking increasingly frontal to me, and I’m not sure if this system has had gale force sustained winds. I’d say I’m against naming this storm.

[euro6208]

WDPN32 PGTW 150900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 08W WARNING
NR 05//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 08W (GAEMI), LOCATED APPROXIMATELY 115 NM
SOUTH OF TAIPEI, TAIWAN, HAS TRACKED EAST-NORTHEASTWARD AT 12 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
SHOWS A SMALL AREA OF PERSISTENT CONVECTION AROUND THE LOW LEVEL
CIRCULATION CENTER (LLCC). THIS CONVECTION IS PART OF A LARGER BAND
OF CONVECTION WHICH SPREADS ACROSS THE REGION. THE INITIAL POSITION
IS BASED ON A 150600Z HIMAWARI VISIBLE SATELLITE IMAGE WHICH SHOWS
THE ELONGATED CLOUD STRUCTURE. THE INITIAL INTENSITY OF 30 KNOTS IS
BASED ON A DVORAK INTENSITY ESTIMATE OF T2.0 (30 KNOTS) FROM RJTD AND
HEDGED SLIGHTLY BELOW A 150508Z SATCON ESTIMATE OF 37 KNOTS.
ENVIRONMENTAL ANALYSIS SHOWS FAVORABLE VERTICAL WIND SHEAR (5 TO 10
KNOTS) AND MODERATE POLEWARD AND EQUATORWARD OUTFLOW CHANNELS. SEA
SURFACE TEMPERATURES REMAIN FAVORABLE (29 TO 30 DEGREES CELSIUS). A
150000Z AMSU TEMPERATURE ANOMALY CROSS-SECTION SHOWS THAT THE WARM
CORE STRUCTURE OF TD 08W HAS IMPROVED FROM THE PREVIOUS 142000Z AMSU
TEMPERATURE ANOMALY CROSS-SECTION. TD 08W IS TRACKING TO THE
EAST-NORTHEAST UNDER THE INFLUENCE OF THE STR (SUBTROPICAL RIDGE)
LOCATED TO THE EAST AND THE APPROACHING WEST TO EAST MOVING SHORTWAVE
TROUGH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TD 08W WILL TRACK TO THE NORTHEAST OVER THE REMAINDER OF THE
FORECAST PERIOD WHILE UNDER THE INFLUENCE OF THE AFOREMENTIONED STR
AND SHORTWAVE TROUGH. TD 08W HAS TRACKED BACK OVER WARM WATER WHICH
WILL ALLOW FOR A SLIGHT INTENSIFICATION TO 35 KNOTS BY TAU 24.
DESPITE THE RECENT IMPROVEMENT IN THE WARM CORE STRUCTURE, AS TD 08W
TRACKS NORTHEASTWARD IT WILL BEGIN TO LOOSE ITS TROPICAL
CHARACTERISTICS AND BECOME EMBEDDED IN THE WESTERLIES. EXTRATROPICAL
TRANSITION WILL BEGIN BY TAU 12 AND EXTRATROPICAL TRANSITION WILL BE
COMPLETE BY TAU 36. DYNAMIC MODEL GUIDANCE IS IN FAIRLY GOOD
AGREEMENT. HOWEVER, THE ECMWF TRACKER CONTINUES TO INDICATE A MORE
EAST-NORTHEASTERLY TRACK. OVERALL, THERE IS HIGH CONFIDENCE IN THE
JTWC FORECAST TRACK.//
NNNN

[euro6208]

07W was more impressive than this.

[euro6208]

WDPN32 PGTW 152100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 08W WARNING
NR 07//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 08W (GAEMI), LOCATED APPROXIMATELY 148 NM
WEST-SOUTHWEST OF KADENA AB, HAS TRACKED EAST-NORTHEASTWARD AT 17
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY INDICATES THAT THE SYSTEM IS UNDERGOING EXTRA-TROPICAL
TRANSITION (ETT) WITH A FRONTAL STRUCTURE AND DEEP CONVECTION
SHEARED PRIMARILY OVER THE NORTHEAST QUADRANT. A 151821Z SSMI 85GHZ
IMAGE AND RADAR IMAGERY ALSO SHOW THE FRONTAL STRUCTURE WITH A
PARTIALLY-EXPOSED, BROAD LOW-LEVEL CIRCULATION CENTER (LLCC)
POSITIONED OVER THE WESTERN EDGE OF AN AREA OF DEEP CONVECTION. DUE
TO THE BROAD NATURE OF THE LLCC, THERE IS INCREASING UNCERTAINTY IN
THE CURRENT POSITION AND TRACK SPEEDS. THE CURRENT INTENSITY IS
ASSESSED AT 35 KNOTS BASED ON RECENT ASCAT DATA SHOWING NUMEROUS 30-
35 KNOT WINDS AND SURFACE OBSERVATIONS INDICATING SLP VALUES NEAR
995MB. OVERALL, THE SYSTEM APPEARS TO HAVE HYBRID CHARACTERISTICS
WITH ASCAT IMAGERY SHOWING A FAIRLY SMALL RADIUS OF MAXIMUM WINDS OF
40-50NM, WHICH IS MORE TYPICAL OF A TROPICAL CYCLONE. HOWEVER, A
RECENT AMSU TEMPERATURE ANOMALY CROSS-SECTION NOW INDICATES A
BROADENING WARM ANOMALY TYPICAL WITH ETT. THE SYSTEM IS CURRENTLY
LOCATED UNDER AN UPPER-LEVEL TROUGH WITH STRONG (25 TO 40 KNOTS)
VERTICAL WIND SHEAR.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE. THE 34-KNOT WIND RADII HAVE
BEEN ADJUSTED SMALLER BASED ON A DETAILED ANALYSIS OF ASCAT IMAGERY
AND SURFACE OBSERVATIONS.
B. TS 08W WILL MAINTAIN A QUICK NORTHEASTWARD TRACK OVER THE
REMAINDER OF THE FORECAST PERIOD AND IS FORECAST TO COMPLETE ETT BY
TAU 24. DYNAMIC MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A 180-NM
SPREAD IN SOLUTIONS AT TAU 36, THEREFORE, THERE IS NOW MODERATE
CONFIDENCE IN THE JTWC FORECAST TRACK. IN GENERAL, THE DYNAMIC
MODELS ARE DIVERGING AS THE SYSTEM BECOMES EXTRA-TROPICAL AND
SEVERAL MODELS ARE TRACKING THE SYSTEM POLEWARD INTO THE MIDLATITUDE
SHORTWAVE TROUGH. THE JTWC FORECAST IS ON THE SOUTHERN EDGE OF THE
AIDS ENVELOPE AND IS CONSISTENT WITH THE PREVIOUS FORECAST.//
NNNN

[euro6208]

[euro6208]

Nago reporting 990.8 and further south Naha 994.9 up from it’s low of 993.7mb. Max winds in Naha gusted to around 55 mpg earlier today.

[euro6208]

[euro6208]

WDPN32 PGTW 160300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 08W WARNING
NR 08//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 08W (GAEMI), LOCATED APPROXIMATELY 45 NM WEST-
NORTHWEST OF KADENA AB, HAS TRACKED EAST-NORTHEASTWARD AT 19
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY INDICATES THAT THE SYSTEM IS UNDERGOING EXTRA-TROPICAL
TRANSITION (ETT) WITH A FRONTAL STRUCTURE AND DEEP CONVECTION
SHEARED OVER THE NORTHEAST QUADRANT. A 152216Z SSMIS 91GHZ
IMAGE AND RADAR IMAGERY ALSO SHOW THE FRONTAL STRUCTURE WITH A
PARTIALLY-EXPOSED, BROAD LOW-LEVEL CIRCULATION CENTER (LLCC)
POSITIONED OVER THE WESTERN EDGE OF AN AREA OF DEEP CONVECTION. DUE
TO THE BROAD NATURE OF THE LLCC, THERE IS INCREASING UNCERTAINTY IN
THE CURRENT POSITION AND TRACK SPEEDS. THE CURRENT INTENSITY IS
ASSESSED AT 35 KNOTS BASED ON SURFACE OBSERVATIONS FROM NAHA AND
KADENA AB INDICATING PEAK SUSTAINED SURFACE WINDS OF 30-35 KNOTS.
OVERALL, THE SYSTEM APPEARS TO HAVE HYBRID CHARACTERISTICS
WITH ASCAT IMAGERY SHOWING A FAIRLY SMALL RADIUS OF MAXIMUM WINDS OF
40-50NM, WHICH IS MORE TYPICAL OF A TROPICAL CYCLONE. HOWEVER, A
RECENT AMSU TEMPERATURE ANOMALY CROSS-SECTION NOW INDICATES A
BROADENING WARM ANOMALY TYPICAL WITH ETT. THE SYSTEM IS CURRENTLY
LOCATED UNDER AN UPPER-LEVEL TROUGH WITH STRONG (30 TO 40 KNOTS)
VERTICAL WIND SHEAR.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE. THE 34-KNOT WIND RADII HAVE
BEEN ADJUSTED SMALLER BASED ON A DETAILED ANALYSIS OF ASCAT IMAGERY
AND SURFACE OBSERVATIONS.
B. TS 08W WILL MAINTAIN A QUICK NORTHEASTWARD TRACK OVER THE
REMAINDER OF THE FORECAST PERIOD AND IS FORECAST TO COMPLETE ETT BY
TAU 24. WITH THE EXCEPTION OF HWRF, DYNAMIC MODEL GUIDANCE IS IN
GOOD AGREEMENT WITH A 80-NM SPREAD IN SOLUTIONS AT TAU 24,
THEREFORE, THERE IS MODERATE CONFIDENCE IN THE JTWC FORECAST TRACK.
IN GENERAL, THE DYNAMIC MODELS ARE DIVERGING AS THE SYSTEM BECOMES
EXTRA-TROPICAL AND SEVERAL MODELS ARE TRACKING THE SYSTEM POLEWARD
INTO THE MIDLATITUDE SHORTWAVE TROUGH. THE JTWC FORECAST IS ON THE
SOUTHERN EDGE OF THE AIDS ENVELOPE AND IS CONSISTENT WITH THE
PREVIOUS FORECAST.//
NNNN

[NotoSans]

Seems that JTWC issued their final warning too early.

[cycloneye]

JMA mantains GAEMI alive.

TS 1806 (Gaemi)
Issued at 09:45 UTC, 16 June 2018

<Analysis at 09 UTC, 16 June>
Scale -
Intensity -
Center position N27°10' (27.2°)
E129°55' (129.9°)
Direction and speed of movement ENE 35 km/h (18 kt)
Central pressure 990 hPa
Maximum wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
≥ 30 kt wind area E 390 km (210 NM)
W 220 km (120 NM)

<Forecast for 21 UTC, 16 June>
Intensity -
Center position of probability circle N28°30' (28.5°)
E131°20' (131.3°)
Direction and speed of movement NE 15 km/h (9 kt)
Central pressure 990 hPa
Maximum wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
Radius of probability circle 60 km (30 NM)

<Forecast for 09 UTC, 17 June>
Intensity -
LOW
Center position of probability circle N29°30' (29.5°)
E132°10' (132.2°)
Direction and speed of movement NE Slow
Central pressure 992 hPa
Maximum sustained wind speed 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 110 km (60 NM)

[doomhaMwx]

Radar imagery clearly shows the circulation center of Tropical Storm Gaemi as it moves away from Okinawa island.

[euro6208]

Yup final warning issued. It's already undergoing ETT transition with frontal characteristics.

WTPN32 PGTW 160900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 08W (GAEMI) WARNING NR 009
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
160600Z --- NEAR 26.9N 128.9E
MOVEMENT PAST SIX HOURS - 085 DEGREES AT 17 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE, RADAR AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
100 NM NORTHWEST QUADRANT
REPEAT POSIT: 26.9N 128.9E
---
FORECASTS:
12 HRS, VALID AT:
161800Z --- 28.1N 130.6E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
090 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 050 DEG/ 10 KTS
---
24 HRS, VALID AT:
170600Z --- 29.4N 132.3E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
RADIUS OF 034 KT WINDS - 125 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
---
REMARKS:
160900Z POSITION NEAR 27.2N 129.3E.
TROPICAL STORM (TS) 08W (GAEMI), LOCATED APPROXIMATELY 64 NM EAST-
NORTHEAST OF KADENA AB, HAS TRACKED EASTWARD AT 17 KNOTS OVER THE
PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY SHOWS
THE CYCLONE IS UNDERGOING EXTRATROPICAL TRANSITION (ETT) WITH DEEP
CONVECTION TO THE NORTHEAST OF THE BROAD LOW LEVEL CIRCULATION
CENTER (LLCC) AND FRONTAL CHARACTERISTICS. CONFIDENCE IN THE INITIAL
POSITION IS LOW BECAUSE THE LLCC IS BROAD. THE CURRENT INTENSITY IS
SET AT 35 KNOTS BASED ON A PARTIAL 160145Z METOP-A ASCAT PASS
SHOWING 35 KNOT WINDS TO THE NORTH OF THE LLCC AND PGTW SUBTROPICAL
DVORAK ESTIMATES OF T2.5 (35 KNOTS). TS 08W IS LOCATED UNDER AN
UPPER-LEVEL TROUGH WITH STRONG VERTICAL WIND SHEAR OF APPROXIMATELY
40 KNOTS. THE CYCLONE IS FORECAST TO TRACK TO THE NORTHEAST AND
COMPLETE ETT IN THE NEXT 12 HOURS. THE OFFICIAL FORECAST TRACK IS
SLIGHTLY SOUTH AND FASTER THAN THE CONSENSUS, CONSISTENT WITH THE
ECMWF AND THE PREVIOUS JTWC FORECAST TRACK. DESPITE THE SHORT
DURATION OF THIS FORECAST, OVERALL CONFIDENCE IN THE FORECAST TRACK
IS LOW BECAUSE OF UNCERTAINTY IN THE INITIAL POSITION AND LARGE
SPREAD IN THE MODEL GUIDANCE. 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 160600Z IS 15 FEET.//
NNNN



TPPN11 PGTW 160907

A. TROPICAL STORM 08W (GAEMI)

B. 16/0840Z

C. 26.93N

D. 129.96E

E. FIVE/HMWRI8

F. ST2.5/2.5

G. IR/EIR/VIS/MSI

H. REMARKS: 63A/PBO PRLY ORGNZD LLCC/ANMTN. ST METHOD YIELDS
2.5.

I. ADDITIONAL POSITIONS: NONE


VEERKAMP

[cycloneye]

JMA still has it.

TS 1806 (Gaemi)
Issued at 18:45 UTC, 16 June 2018

<Analysis at 18 UTC, 16 June>
Scale -
Intensity -
Center position N27°35' (27.6°)
E132°40' (132.7°)
Direction and speed of movement E 30 km/h (17 kt)
Central pressure 992 hPa
Maximum wind speed near center 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
≥ 30 kt wind area E 390 km (210 NM)
W 220 km (120 NM)

<Forecast for 06 UTC, 17 June>
Intensity -
LOW
Center position of probability circle N28°30' (28.5°)
E133°50' (133.8°)
Direction and speed of movement NE 15 km/h (7 kt)
Central pressure 992 hPa
Maximum sustained wind speed 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 60 km (30 NM)

<Forecast for 18 UTC, 17 June>
Intensity -
LOW
Center position of probability circle N29°55' (29.9°)
E135°00' (135.0°)
Direction and speed of movement NE 15 km/h (9 kt)
Central pressure 994 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 110 km (60 NM)

[euro6208]

TPPN11 PGTW 162200

A. REMNANTS OF TROPICAL STORM 08W (GAEMI)

B. 16/2100Z

C. 28.15N

D. 131.57E

E. THREE/HMWRI8

F. XT2.5/2.5

G. IR/EIR/VIS/MSI

H. REMARKS: 19A/PBO XPSD LLCC/ANMTN. WELL ORGANIZED LLCC WITH
NO CONVECTION AND FORWARD SPEED OF 8 KTS WRAPS 0.20 ON LOG10
SPIRAL YIELDING XT2.5. XT METHOD USED DUE TO FRONTAL
INTERACTION.

I. ADDITIONAL POSITIONS:
16/1804Z 28.27N 131.18E SSMI


ZOUFALY

[euro6208]

[euro6208]

Gaemi > < Unnamed TS.

Someone is screwd.

[doomhaMwx]

LOW
Issued at 00:50 UTC, 17 June 2018

<Analysis at 00 UTC, 17 June>
Scale -
Intensity -
LOW
Center position N29°00' (29.0°)
E133°00' (133.0°)
Direction and speed of movement ENE 20 km/h (10 kt)
Central pressure 996 hPa