WPAC: LEEPI - Tropical Storm

[Meow]

TD02 in the atl looked the same way as this system over 24 hours ago but still no upgrade although this is more organized with plenty of convection...weird

PGTW- 1.5
KNES- 1.0

At least JMA, HKO, CWB and PAGASA upgraded it to a TD.

[Hurricane_Luis]

Tropical Depression Emong (Future TS Leepi)

[Meow]

Tropical Storm Leepi



TS 1304 (LEEPI)
Issued at 01:20 UTC, 18 June 2013

<Analyses at 18/00 UTC>
Scale -
Intensity -
Center position N16°35'(16.6°)
E126°35'(126.6°)
Direction and speed of movement N 20km/h(10kt)
Central pressure 998hPa
Maximum sustained wind speed 18m/s(35kt)
Maximum wind gust speed 25m/s(50kt)
Area of 30kt winds or more NE600km(325NM)
SW330km(180NM)

<Forecast for 19/00 UTC>
Intensity -
Center position of probability circle N21°35'(21.6°)
E125°55'(125.9°)
Direction and speed of movement N 25km/h(13kt)
Central pressure 994hPa
Maximum wind speed near the center 20m/s(40kt)
Maximum wind gust speed 30m/s(60kt)
Radius of probability circle 220km(120NM)

<Forecast for 20/00 UTC>
Intensity -
Center position of probability circle N26°25'(26.4°)
E125°00'(125.0°)
Direction and speed of movement N 20km/h(12kt)
Central pressure 990hPa
Maximum wind speed near the center 23m/s(45kt)
Maximum wind gust speed 35m/s(65kt)
Radius of probability circle 370km(200NM)

<Forecast for 21/00 UTC>
Intensity -
Center position of probability circle N31°00'(31.0°)
E127°55'(127.9°)
Direction and speed of movement NNE 25km/h(13kt)
Central pressure 990hPa
Maximum wind speed near the center 23m/s(45kt)
Maximum wind gust speed 35m/s(65kt)
Radius of probability circle 460km(250NM)

[RobWESTPACWX]

What I anticipate for Okinawa from Leepi.

[xtyphooncyclonex]

JTWC's latest update:
IT IS A TROPICAL STORM ALREADY!!!

WTPN31 PGTW 180900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 04W (LEEPI) WARNING NR 003
UPGRADED FROM TROPICAL DEPRESSION 04W
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
180600Z --- NEAR 18.4N 126.3E
MOVEMENT PAST SIX HOURS - 350 DEGREES AT 14 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 18.4N 126.3E
---
FORECASTS:
12 HRS, VALID AT:
181800Z --- 21.0N 126.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 360 DEG/ 15 KTS
---
24 HRS, VALID AT:
190600Z --- 24.0N 126.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 015 DEG/ 16 KTS
---
36 HRS, VALID AT:
191800Z --- 27.0N 126.9E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 035 DEG/ 17 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
200600Z --- 29.8N 129.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 060 DEG/ 22 KTS
---
72 HRS, VALID AT:
210600Z --- 34.1N 138.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 065 DEG/ 34 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
220600Z --- 38.7N 153.7E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
180900Z POSITION NEAR 19.1N 126.2E.
TROPICAL STORM 04W (LEEPI), LOCATED APPROXIMATELY 493 NM SOUTHWARD OF
KADENA AB, HAS TRACKED NORTHWARD AT 14 KNOTS OVER THE PAST SIX HOURS.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 180600Z IS 12 FEET. NEXT
WARNINGS AT 181500Z, 182100Z, 190300Z AND 190900Z. //
NNNN

[RobWESTPACWX]

Hey all, Im running a live cast at 03UTC on Wednesday if anyone wants to join in, it will be live on the link below. A chatroom is available there for any questions or comments, also post anything here if you want.

http://www.westernpacificweather.com/cu ... orm-track/

[Meow]

We can notice that JMA uses ‘Maximum sustained wind speed’ instead of ‘Maximum wind speed near the center’ to Leepi.

[euro6208]

The name leepi reminds me of Pokemon.

[euro6208]

WTPN31 PGTW 181500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 04W (LEEPI) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
181200Z --- NEAR 19.5N 126.3E
MOVEMENT PAST SIX HOURS - 360 DEGREES AT 11 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 19.5N 126.3E
---
FORECASTS:
12 HRS, VALID AT:
190000Z --- 22.3N 126.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 000 DEG/ 15 KTS
---
24 HRS, VALID AT:
191200Z --- 25.3N 126.2E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 020 DEG/ 12 KTS
---
36 HRS, VALID AT:
200000Z --- 27.6N 127.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 035 DEG/ 15 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
201200Z --- 30.0N 129.1E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
085 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
075 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 060 DEG/ 27 KTS
---
72 HRS, VALID AT:
211200Z --- 34.7N 140.6E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 070 DEG/ 34 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
221200Z --- 38.7N 156.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
181500Z POSITION NEAR 20.2N 126.2E.
TROPICAL STORM 04W (LEEPI), LOCATED APPROXIMATELY 428 NM SOUTHWARD OF
KADENA AB, OKINAWA, JAPAN, HAS TRACKED NORTHWARD AT 11 KNOTS OVER
THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 181200Z IS 12
FEET. NEXT WARNINGS AT 182100Z, 190300Z, 190900Z AND 191500Z. //
NNNN

[RobWESTPACWX]

Hey all, my latest video webcast on this storm. Also running a live one at 03UTC if anyone wants to check it out.

[youtube]http://www.youtube.com/watch?v=EhLx0CYnNYE[/youtube]

[euro6208]

WTPN31 PGTW 190900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 04W (LEEPI) WARNING NR 007
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
190600Z --- NEAR 22.6N 125.3E
MOVEMENT PAST SIX HOURS - 345 DEGREES AT 12 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 22.6N 125.3E
---
FORECASTS:
12 HRS, VALID AT:
191800Z --- 25.2N 125.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 005 DEG/ 12 KTS
---
24 HRS, VALID AT:
200600Z --- 27.6N 125.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 025 DEG/ 11 KTS
---
36 HRS, VALID AT:
201800Z --- 29.6N 126.3E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 065 DEG/ 23 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
210600Z --- 31.6N 131.1E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
VECTOR TO 72 HR POSIT: 075 DEG/ 32 KTS
---
72 HRS, VALID AT:
220600Z --- 33.9N 146.0E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
190900Z POSITION NEAR 23.3N 125.2E.
TROPICAL STORM 04W (LEEPI), LOCATED APPROXIMATELY 271 NM SOUTH-
SOUTHWESTWARD OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED
NORTH-NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 190600Z IS 15 FEET. NEXT WARNINGS AT
191500Z, 192100Z, 200300Z AND 200900Z. //
NNNN


WDPN31 PGTW 190900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 04W (LEEPI)
WARNING NR 07//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 04W (LEEPI), LOCATED APPROXIMATELY 271 NM SOUTH-
SOUTHWESTWARD OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED
NORTH-NORTHWESTWARD AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS FRAGMENTED CONVECTIVE
BANDS WRAPPING INTO A POORLY DEFINED LOW-LEVEL CIRCULATION CENTER
(LLCC). THE INITIAL POSITION IS BASED ON THE MSI LOOP WITH POOR
CONFIDENCE. THE INITIAL INTENSITY IS BASED ON CONGRUENT DVORAK
ESTIMATES FROM PGTW AND RJTD. UPPER-LEVEL ANALYSIS INDICATES A
FAVORABLE ENVIRONMENT WITH LIGHT TO MODERATE (10-20 KNOT) VERTICAL
WIND SHEAR (VWS) ENHANCED BY STRONG RADIAL OUTFLOW. ALONG-TRACK SEA
SURFACE TEMPERATURES (SSTS) ARE ALSO FAVORABLE AT 28-30 DEGREES
CELSIUS. TS 04W CONTINUES TO TRACK ALONG THE WESTERN PERIPHERY OF A
DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE EAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS LEEPI WILL CONTINUE TO TRACK POLEWARD OVER THE NEXT 24
HOURS. AFTERWARDS, IT WILL ROUND THE STR AND ACCELERATE NORTHEASTWARD
AS IT BECOMES EMBEDDED IN THE PREVAILING WESTERLIES. TS 04W WILL
EXPERIENCE MODERATE INTENSIFICATION AS FAVORABLE VWS AND SSTS
PERSIST. PEAK INTENSIFICATION IS EXPECTED AT TAU 24-36 WITH
INCREASED OUTFLOW FROM INITIAL EXPOSURE TO THE STRONG WESTERLY WINDS.
INCREASING VWS AND DECREASING SSTS WILL LEAD TO THE DETERIORATION OF
THE SYSTEM SOON AFTER. AFTER TAU 48, TS 04W WILL FURTHER ACCELERATE
INTO THE MID-LATITUDES AND COMMENCE EXTRATROPICAL TRANSITION,
BECOMING A COLD-CORE LOW BY TAU 72. DYNAMIC MODEL GUIDANCE CONTINUES
TO BE IN TIGHT AGREEMENT, LENDING HIGH CONFIDENCE TO THE FORECAST
TRACK, WHICH IS INITIALLY LAID SLIGHTLY RIGHT OF MODEL CONSENSUS
(CONW) AND THEN FASTER THAN CONW AFTER TAU 36. //
NNNN

[euro6208]

Leepi lashing MiyakoJima/Yaeyama...

[vrif]

Leepi looks lopsided from the latest OSCAT.

[vrif]

40 Knots+ winds on the south side of Leepi at 200103Z from the ASCAT-B

[mrbagyo]

look at those "sheared vortices"????


Uploaded with ImageShack.us

[euro6208]

downgraded to a TD based on a OSCAT showing 30 knot winds...

WDPN31 PGTW 200300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 04W (LEEPI)
WARNING NR 10//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 04W (LEEPI), LOCATED APPROXIMATELY 132 NM
WEST-NORTHWESTWARD OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED
NORTHWARD AT 16 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS A SERIES OF SMALLER
CIRCULATIONS LOCATED WITHIN A LARGER SCALE TOROIDAL CIRCULATION. THE
CURRENT POSITION HAS BEEN LOCATED AT THE CENTER OF THE TOROID,
REFLECTING THE POSITION OF GREATEST TURNING. BASED ON AN OLDER
191455Z OSCAT PASS SHOWING WIND SPEEDS ON THE ORDER OF 30 KNOTS, THE
CURRENT INTENSITY HAS BEEN DECREASED TO ACCOUNT FOR THE WEAKENING
OBSERVED IN MSI. UPPER LEVEL ANALYSIS INDICATES THE ANTICYCLONE
LOCATED OVER EASTERN CHINA HAS BEEN INTERACTING WITH A TUTT CELL TO
THE EAST OF TD 04W, CREATING MODERATE TO HIGH LEVELS OF VERTICAL
WIND SHEAR (VWS) (20 TO 30 KNOTS). THIS INCREASE IN VWS HAS CAUSED
THE LOW LEVEL TO BECOME FULLY EXPOSED. TD 04W CONTINUES TO TRACK
NORTHWARD AROUND THE WESTERN PERIPHERY OF A LOW- TO MID-LEVEL
SUBTROPICAL RIDGE (STR). SEA SURFACE TEMPERATURES (SSTS) REMAIN
FAVORABLE (28 TO 29 DEGREES CELSIUS).
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 04W WILL CONTINUE TO TRACK POLEWARD OVER THE NEXT 06 TO 12
HOURS AROUND THE STR, ROUNDING THE NORTHWESTERN PERIPHERY, AND
TRANSITIONING TO AN EAST-NORTHEASTWARD TRACK. THE SYSTEM WILL BECOME
EMBEDDED WITHIN THE MID-LATITUDE WESTERLIES BETWEEN TAU 12 AND 24,
TRACKING THE LOW LEVEL OVER SOUTHERN KYUSHU INTO THE NORTHERN
PACIFIC OCEAN. DUE TO THE TRACK OVER LAND, HARSH UPPER LEVEL
ENVIRONMENT (HIGH LEVELS OF VWS) AND UNFAVORABLE SSTS, THE SYSTEM
WILL UNDERGO A TRANSITION FROM A WARM-CORE TROPICAL TO A COLD-CORE
EXTRATROPICAL SYSTEM BY TAU 48. HOWEVER, THERE ARE SOME INDICATIONS
THIS PROCESS COULD OCCUR MORE RAPIDLY AS IT TRACKS OVER KYUSHU.
DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT, LEADING TO HIGH
CONFIDENCE IN THE FORECAST TRACK.//
NNNN

[RobWESTPACWX]

This storm has got some help right now though, a frontal area over Japan cuasing landslides floods winds over 100kph. All sorts of fun.

[dexterlabio]

for some reason, the JTWC latest warning shows a TS, and there are no indication that it was downgraded to a TD earlier...

[vrif]

JTWC's final warning

WDPN31 PGTW 201500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 04W (LEEPI) WARNING NR
12//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 04W (LEEPI), LOCATED APPROXIMATELY 282 NM
SOUTHWESTWARD OF SASEBO, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD
AT 12 KNOTS OVER THE PAST SIX HOURS. ANIMATED INFRARED (IR)
SATELLITE IMAGERY CONTINUES TO DEPICT MULTIPLE VORTICES ROTATING
AROUND A CENTROID WITH RAPIDLY DECAYING DEEP CONVECTION OVER THE
SOUTH QUADRANT. A 201056Z SSMIS IMAGE, HOWEVER, DEPICTS WELL-DEFINED
SHALLOW BANDING WRAPPING INTO THE LOW-LEVEL CIRCULATION CENTER
(LLCC). THE INITIAL POSITION IS BASED ON THE CENTROID POSITION USING
THE AFOREMENTIONED SSMIS IMAGE WITH FAIR CONFIDENCE. THE SYSTEM IS
JUST BEGINNING TO INTERACT WEAKLY WITH THE BAROCLINIC ZONE (BAIU
BOUNDARY) POSITIONED NEAR CHEJU ISLAND. THE INITIAL INTENSITY IS
ASSESSED AT 35 KNOTS, SLIGHTLY HIGHER THAN DVORAK CURRENT INTENSITY
ESTIMATES, BASED ON THE WELL-DEFINED STRUCTURE, RECENT SCATTEROMETER
DATA AND A SATCON ESTIMATE OF 40 KNOTS. TS 04W IS LOCATED WITHIN AN
UNFAVORABLE ENVIRONMENT CHARACTERIZED BY MODERATE VWS AND WEAK
INTERACTION WITH THE BAIU BOUNDARY. SEA SURFACE TEMPERATURES REMAIN
MARGINALLY FAVORABLE AT 26 TO 27 DEGREES CELSIUS.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TS 04W IS FORECAST TO ROUND THE SUBTROPICAL RIDGE AXIS WITHIN
THE NEXT 12 HOURS THEN ACCELERATE EASTWARD AS IT BEGINS TO ENCOUNTER
MIDLATITUDE WESTERLY FLOW. THE SYSTEM WILL BEGIN EXTRA-TROPICAL
TRANSITION (ETT) BY TAU 12 THEN COMPLETE ETT BY TAU 36 AS IT
TRANSITIONS INTO A COLD-CORE SYSTEM. DYNAMIC MODEL GUIDANCE REMAINS
IN TIGHT AGREEMENT, THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC
FORECAST TRACK. TS 04W WILL GRADUALLY WEAKEN AS IT INTERACTS WITH
LAND AFTER TAU 12 AND ENCOUNTERS STRONG VWS BUT IS EXPECTED TO
MAINTAIN TROPICAL DEPRESSION STRENGTH THROUGH THE REMAINDER OF THE
FORECAST PERIOD.//
NNNN




WTPN31 PGTW 202100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/

REMARKS:
202100Z POSITION NEAR 31.5N 127.3E.
TROPICAL DEPRESSION 04W (LEEPI), LOCATED APPROXIMATELY 215 NM WEST-
SOUTHWESTWARD OF SASEBO, JAPAN, HAS TRACKED NORTH-NORTHEASTWARD AT
14 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY SHOWS THE LOW LEVEL CIRCULATION CENTER HAS STARTED
TO ELONGATE AS THE INTERACTION WITH THE BAROCLINIC ZONE (BAIU
BOUNDARY) POSITIONED NEAR CHEJU ISLAND AMPLIFIES. THE SYSTEM HAS
STARTED THE PROCESS OF EXTRA-TROPICAL TRANSITION (ETT) AND IS
EXPECTED TO COMPLETE THE ETT PROCESS IN THE NEXT 12 HOURS. THE
CURRENT FORECAST EXTENDS THE ET POSITIONS THROUGH TAU 36, AS MODEL
GUIDANCE INDICATES THE SYSTEM WILL INTENSIFY AS A COLD-CORE LOW
ALONG THE SOUTHERN COAST OF JAPAN INTO THE WESTERN PACIFIC. MODERATE
TO HIGH (25 TO 30 KNOTS) OF VERTICAL WIND SHEAR, IN ASSOCIATION WITH
INCREASED BAROCLINIC INTERACTION, AND DECREASING SEA SURFACE
TEMPERATURES HAVE LED TO A FASTER THAN EXPECTED TRANSITION OF THE
SYSTEM. DYNAMIC MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT,
THEREFORE, THERE IS HIGH CONFIDENCE IN THE JTWC FORECAST TRACK. 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 201800Z IS 12 FEET.
REFER TO TROPICAL DEPRESSION 05W (FIVE) WARNINGS (WTPN32 PGTW) FOR
SIX-HOURLY UPDATES.//
NNNN

[Meow]

Extratropical



LOW
Issued at 00:50 UTC, 21 June 2013

<Analyses at 21/00 UTC>
Scale -
Intensity -
LOW
Center position N32°00'(32.0°)
E127°00'(127.0°)
Direction and speed of movement ENE 30km/h(15kt)
Central pressure 1002hPa