WPAC: LEKIMA - Post-Tropical

[euro6208]

 https://twitter.com/iCyclone/status/1159454638883528704

[mrbagyo]

It appears that the island of Tarama (between Ishigaki and Miyako islands) will get a direct hit from the eye within the next hour or two.

https://i.imgur.com/QC2xo4S.jpg
https://i.imgur.com/Xg3KjBz.png

No METAR available from Tarama (RORT)
Sad

[euro6208]

Clearly a Cat 5 when you add up all the data.

[doomhaMwx]

It appears that the island of Tarama (between Ishigaki and Miyako islands) will get a direct hit from the eye within the next hour or two.

https://i.imgur.com/QC2xo4S.jpg
https://i.imgur.com/Xg3KjBz.png

No METAR available from Tarama (RORT)
Sad

And looks like the station there went down?

[doomhaMwx]

The eye missed Tarama island.



Miyako island to the east recorded a SLP of 961mb at 11pm JST.

[mrbagyo]

Tarama Island and Typhoon Lekima in a nutshell

[dexterlabio]

There we go, never having a direct observation or sampling of strongest winds in Lekima at its peak. Although I suppose the data obtained from the islands are enough to perform the math and have a more reliable estimate of Lekima's strength.

[NotoSans]

AMSU estimate at 13Z at 912mb/128kt. Given the concentric eyewall structure, a slight mismatch between winds and pressure would not be surprising.

Can also use surface observations from Miyakojima to produce a pressure estimate via Schloemer analysis.

[doomhaMwx]

Miyako island to the east recorded a SLP of 961mb at 11pm JST.

https://i.imgur.com/Sn9iPlc.png

Pressure already on the rise. Minimum SLP probably went down to 950's between 11pm-12am JST?

[euro6208]

WDPN31 PGTW 081500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 10W (LEKIMA) WARNING
NR 19//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUPER TYPHOON (STY) 10W (LEKIMA), LOCATED APPROXIMATELY 190 NM
EAST-SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED NORTHWESTWARD AT 10
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY SHOWS THE SYSTEM HAS MAINTAINED A TIGHTLY COMPACT CENTRAL
CONVECTION WITH ANNULAR CHARACTERISTICS AND A SHARPLY OUTLINED 10-NM
EYE. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE
EYE FEATURE. THE INITIAL INTENSITY OF 130KTS IS BASED ON THE DVORAK
ESTIMATES OF T6.5/127KTS FROM PGTW AND RJTD AND REFLECTS THE
SUSTAINED CONVECTIVE STRUCTURE. ENVIRONMENTAL ANALYSIS INDICATES
EXCELLENT RADIAL OUTFLOW, LOW VERTICAL WIND SHEAR (VWS) AND WARM SST
(30C). STY 10W IS TRACKING ALONG THE SOUTHWEST PERIPHERY OF A
SUBTROPICAL RIDGE (STR) TO THE NORTHEAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. STY 10W WILL CONTINUE ON ITS CURRENT NORTHWESTWARD TRACK UNDER
THE INFLUENCE OF THE STR, MOVING MORE NORTHWARD AFTER TAU 36 AS THE
STR REORIENTS AND RECEDES SLIGHTLY TO THE EAST AND AS THE SYSTEM
REACH THE EAST COAST OF CHINA JUST SOUTH OF TAIZHOU. INCREASING VWS
AND LAND INTERACTION WILL BEGIN TO WEAKEN THE SYSTEM DOWN TO 45 KNOTS
BY TAU 72, AFTER TRACKING PAST SHANGHAI. THE LIMITED NUMERICAL MODEL
GUIDANCE IS IN GOOD AGREEMENT WITH A GRADUAL SPREADING IN SOLUTIONS
BY TAU 72, LENDING FAIR CONFIDENCE IN THIS PORTION OF THE JTWC
FORECAST TRACK.
C. AFTER TAU 72, STY LEKIMA WILL TURN MORE NORTH-NORTHWESTWARD AND
FURTHER INLAND ALONG THE WESTERN PERIPHERY OF THE BUILDING STR. RAPID
WEAKENING IS EXPECTED PRIMARILY DUE TO LAND INTERACTION, LEADING TO
DISSIPATION BY TAU 96. NUMERICAL MODELS SIGNIFICANTLY DIVERGE IN ALL
DIRECTIONS AS THEY LOSE THE WEAK VORTEX, THEREFORE, THERE IS LOW
CONFIDENCE IN THE EXTENDED PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[doomhaMwx]

Saved close-up radar loop, 22:00-00:00 JST.

[TropicalAnalystwx13]

Clearly a Cat 5 when you add up all the data.

What data? CIMSS ADT is at T6.8/134.8kt. SAB is at T6.5/125kt. AMSU is at 128kt.

[Highteeld]

From the CMA

[SUBJECTIVE FORECAST
SuperTY LEKIMA 1909 (1909) INITIAL TIME 081500 UTC
00HR 24.8N 124.8E 915HPA 62M/S
30KTS WINDS 320KM NORTHEAST
380KM SOUTHEAST
380KM SOUTHWEST
300KM NORTHWEST
50KTS WINDS 140KM NORTHEAST
140KM SOUTHEAST
140KM SOUTHWEST
140KM NORTHWEST
64KTS WINDS 65KM NORTHEAST
65KM SOUTHEAST
65KM SOUTHWEST
65KM NORTHWEST
MOVE NW 22KM/H]

[Highteeld]

#terraphobia

 https://twitter.com/weatherchannel/status/1159501256412598272

[1900hurricane]

While maybe not a slam dunk, I do think there is plenty of evidence to support a maximum intensity just exceeding the category 5 threshold. One of the strongest cases would be a proper Dvorak analysis at 12Z August 8th. JMA went up to 105 kt at that time, which is their T7.0 intensity, but JTWC weirdly got a 6.0. Microwave intensity estimates also largely supported a 135-140 kt system, including 139 kt SSMIS, 136 kt ATMS, and a 141 kt AMSU, although all at slightly different times. ADT only made it as high as 6.8 (with raw 7.0), but it can be argued that Western Pacific ADT could have a low bias at the higher intensities (Mangkhut '18 may be the most extreme example).

With all that being said, I would probably set maximum intensity at 135 kt at 12Z August 8th, with a fairly quick drop off after that due to eyewall replacement. Individual data points do support category 5 intensity, but usually either briefly or somewhat sporadically vs the other data at the time. I could easily change my mind if James provides an impressive barograph to run Schloemer on though.

[1900hurricane]

Also, rather curiously I might add, the 08Z August 8th eye temperature just clipped into warm medium grey when using normal full disk Himawari-8 imagery, which is verifiable by ADT data. The mesoscale window did not pick up an eye temperature quite as warm at the time, remaining very deep off-white.

[1900hurricane]

JTWC's OCI at 00Z is 988 mb. That's silly low, and probably too low honestly.

[1900hurricane]

Very clear to see eyewall replacement on visible imagery at the moment.

[euro6208]

WDPN31 PGTW 090300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 10W (LEKIMA) WARNING NR 21//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON (TY) 10W (LEKIMA), LOCATED APPROXIMATELY 236 NM WEST OF
KADENA AB, HAS TRACKED NORTHWESTWARD AT 14 KNOTS (KTS) OVER THE PAST
SIX HOURS. A 5-10 NM ROUND EYE IN ANIMATED MULTISPECTRAL SATELLITE
IMAGERY PROVIDES HIGH CONFIDENCE IN THE INITIAL POSITION. DESPITE
THE EYE REMAINING SMALL AND ROUND, ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY REVEALS THE SURROUNDING CONVECTION HAS BECOME
ASYMMETRIC WITH WARMER CLOUD TOP TEMPERATURES ON THE NORTHERN SIDE.
THE INITIAL INTENSITY OF 115 KTS IS BETWEEN CURRENT INTENSITY
ESTIMATES FROM T5.5-6.5 (102-127 KTS). THE ENVIRONMENT WITH GOOD
POLEWARD OUTFLOW, FAIR EQUATORWARD OUTFLOW, LOW (10-15 KT) VERTICAL
WIND SHEAR (VWS), AND WARM (29-30 CELSIUS) SEA SURFACE TEMPERATURE
IS SUPPORTIVE BUT THERE DOES APPEAR TO BE SOME COMPARATIVELY DRY AIR
ENTRAINING IN FROM THE WEST THAT IS LIKELY CONTRIBUTING TO THE
WEAKENING SEEN OVER THE PAST 12 HOURS. TY 10W IS TRACKING ALONG THE
SOUTHWEST PERIPHERY OF A SUBTROPICAL RIDGE (STR).
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. SHORTLY AFTER MAKING LANDFALL ABOUT 140 NM SOUTH OF SHANGHAI,
CHINA AROUND TAU 18, TY 10W WILL BEGIN TRACKING NORTHWARD AS THE STR
REORIENTS AND RECEDES SLIGHTLY TO THE EAST. THE SYSTEM SHOULD PASS
NEAR SHANGHAI ON A NORTHWARD TRACK AROUND TAU 40 AND PASS BRIEFLY
OVER THE YELLOW SEA ON A NORTH-NORTHWESTWARD TRACK BEFORE MAKING
SECOND LANDFALL NEAR QINGDAO, CHINA PRIOR TO TAU 72. LAND
INTERACTION IS EXPECTED TO WEAKEN THE SYSTEM TO 50 KNOTS BY TAU 72.
THE INTENSITY FORECAST IS VERY UNCERTAIN BECAUSE SMALL SHIFTS IN THE
TRACK COULD SIGNIFICANTLY IMPACT THE AMOUNT OF WEAKENING DUE TO LAND
INTERACTION. NUMERICAL MODEL TRACK GUIDANCE IS IN GOOD AGREEMENT FOR
THIS PORTION OF THE FORECAST, LENDING TO GOOD CONFIDENCE IN THE JTWC
TRACK FORECAST THROUGH TAU 72.
C. BETWEEN TAU 72 AND 120, TY 10W IS EXPECTED TO CONTINUE
TRACKING NORTH-NORTHWESTWARD AND BEGIN ROUNDING THE STR AXIS. HIGH
VWS AND LAND INTERACTION ARE EXPECTED TO CONTINUE WEAKENING THE
SYSTEM, HOWEVER UNCERTAINTY IN THE INTENSITY FORECAST REMAINS HIGH
DUE TO UNCERTAINTY IN THE AMOUNT OF LAND INTERACTION. NUMERICAL
MODEL SPREAD INCREASES SIGNIFICANTLY AS SEVERAL MODELS (ECMWF,
GALWEM, UKMET) FOLLOW THE RECURVE SCENARIO WHILE THE OTHER MEMBERS
SHOW THE SYSTEM TURNING SOUTHWARD, POSSIBLY DUE TO DIRECT CYCLONE
INTERACTION WITH TY 11W. THE JTWC TRACK FORECAST FAVORS THE RECURVE
SCENARIO WITH LOW CONFIDENCE DUE TO MAJOR DIFFERENCES IN THE TRACK
BETWEEN THE TWO FEASIBLE FORECAST SCENARIOS.//
NNNN

[arlwx]

WTPN31 PGTW 090900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TYPHOON 10W (LEKIMA) WARNING NR 022//
RMKS/
1. TYPHOON 10W (LEKIMA) WARNING NR 022
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
090600Z --- NEAR 27.0N 122.5E
MOVEMENT PAST SIX HOURS - 305 DEGREES AT 10 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 105 KT, GUSTS 130 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 075 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 140 NM NORTHEAST QUADRANT
175 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 240 NM NORTHEAST QUADRANT
295 NM SOUTHEAST QUADRANT
195 NM SOUTHWEST QUADRANT
165 NM NORTHWEST QUADRANT
REPEAT POSIT: 27.0N 122.5E
---
FORECASTS:
12 HRS, VALID AT:
091800Z --- 28.3N 121.3E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
020 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 290 NM NORTHEAST QUADRANT
320 NM SOUTHEAST QUADRANT
220 NM SOUTHWEST QUADRANT
150 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 335 DEG/ 09 KTS
---
24 HRS, VALID AT:
100600Z --- 29.9N 120.5E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
010 NM SOUTHWEST QUADRANT
000 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 270 NM NORTHEAST QUADRANT
310 NM SOUTHEAST QUADRANT
180 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 360 DEG/ 11 KTS
---
36 HRS, VALID AT:
101800Z --- 32.0N 120.4E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 240 NM NORTHEAST QUADRANT
240 NM SOUTHEAST QUADRANT
140 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 355 DEG/ 14 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
110600Z --- 34.7N 120.2E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 230 NM NORTHEAST QUADRANT
200 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 345 DEG/ 07 KTS
---
72 HRS, VALID AT:
120600Z --- 37.2N 119.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 145 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
155 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 355 DEG/ 02 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
130600Z --- 38.1N 119.2E
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 - 040 NM NORTHEAST QUADRANT
000 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
VECTOR TO 120 HR POSIT: 040 DEG/ 04 KTS
---
120 HRS, VALID AT:
140600Z --- 39.3N 120.4E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
---
REMARKS:
090900Z POSITION NEAR 27.3N 122.2E.
09AUG19. TYPHOON 10W (LEKIMA), LOCATED APPROXIMATELY 126 NM
NORTH-NORTHEAST OF TAIPEI, TAIWAN, HAS TRACKED NORTHWESTWARD AT
10 KNOTS OVER THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
090600Z IS 42 FEET. NEXT WARNINGS AT 091500Z, 092100Z, 100300Z AND
100900Z. REFER TO TYPHOON 11W (KROSA) WARNINGS (WTPN33 PGTW)
FOR SIX-HOURLY UPDATES.//
NNNN