WPAC: KROSA - Tropical Storm

[euro6208]

although under very favorable sst of 29C, wind shear is kinda harsh. An anticyclone is helping to consolidate the distubance but shear increases along the track.

It will have a very hard time to develop.

[euro6208]

Moderate chance for development.

[euro6208]

Latest Surface Analysis shows a LPA just west of guam.

[euro6208]

[Alyono]

it's already developed. Sat data is quite clear on that.

Could be near typhoon intensity by the time it reaches the Philippines

[ManilaTC]

PAGASA issues first warning, names TD as VINTA

Weather Bulletin Number ONE
Tropical Cyclone Alert: Tropical Depression "VINTA"
Issued at 5:00 a.m., Tuesday, 29 October 2013 The Tropical Depression outside the Philippine Area Of Responsibility (PAR) is expected to enter this morning and will be named "VINTA".

Location of Center:
(as of 4:00 a.m.) 1,150 km East of Virac, Catanduanes
Coordinates: 14.5°N, 135.7°E
Strength: Maximum sustained winds of 45 kph near the center

Movement: Forecast to move West Northwest at 24 kph

Forecast Positions/Outlook: Wednesday morning:
600 km East Northeast of Virac, Catanduanes
Thursday morning:
300 km East of Baler, Aurora
Friday morning:
180 km West of Baguio City

[euro6208]

96W INVEST 131028 2000 16.0N 135.0E WPAC 25 1004

[euro6208]

29th storm of the season and forecast to become a typhoon hitting the philippines...here we go!


WTPN31 PGTW 290300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING
REF A/JOINT TYPHOON WRNCEN PEARL HARBOR HI//281051Z OCT 13//
AMPN/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. TROPICAL DEPRESSION 29W (TWENTYNINE) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
290000Z --- NEAR 15.3N 134.5E
MOVEMENT PAST SIX HOURS - 290 DEGREES AT 13 KTS
POSITION ACCURATE TO WITHIN 035 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 15.3N 134.5E
---
FORECASTS:
12 HRS, VALID AT:
291200Z --- 15.5N 131.8E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 275 DEG/ 14 KTS
---
24 HRS, VALID AT:
300000Z --- 15.8N 129.0E
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 275 DEG/ 14 KTS
---
36 HRS, VALID AT:
301200Z --- 16.0N 126.0E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 280 DEG/ 15 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
310000Z --- 16.6N 122.9E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 285 DEG/ 15 KTS
---
72 HRS, VALID AT:
010000Z --- 18.0N 117.0E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
020 NM SOUTHEAST QUADRANT
020 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 115 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
115 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 285 DEG/ 14 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
020000Z --- 19.2N 111.1E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 290 DEG/ 11 KTS
---
120 HRS, VALID AT:
030000Z --- 20.6N 106.6E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
290300Z POSITION NEAR 15.3N 133.8E.
TROPICAL DEPRESSION 29W (TWENTYNINE), LOCATED APPROXIMATELY 784
NM EASTW OF MANILA, PHILIPPINES, HAS TRACKED WEST-NORTHWESTWARD
AT 13 KNOTS OVER THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 290000Z IS 10 FEET. NEXT WARNINGS AT 290900Z, 291500Z,
292100Z AND 300300Z. THIS WARNING SUPERSEDES AND CANCELS REF A,
JOINT TYPHOON WRNCEN PEARL HARBOR HI 281051Z OCT 13 TROPICAL
CYCLONE FORMATION ALERT (WTPN21 PGTW 281100). //
NNNN

[dexterlabio]

Convection is quite fragmented, yes, but the structure looks good to me. It's got a nice banding to its north.

[euro6208]

Prognostic Reasoning.

WTDN31 PGTW 290300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 29W
(TWENTYNINE) WARNING NR 01//
RMKS//
/1. FOR METEOROLOGISTS
2. 6-HOUR SUMMARY AND ANALYSIS:
TROPICAL DEPRESSION (TD) 29W (TWENTYNINE), LOCATED
APPROXIMATELY 784 NM EAST OF MANILA, PHILIPPINES, HAS TRACKED
WEST-NORTHWESTWARD AT 13 KNOTS OVER THE PAST SIX HOURS. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THAT EVEN AS THE
ASSOCIATED CONVECTION REMAINED SHALLOW, THE FORMATIVE BANDS
HAVE WRAPPED TIGHTER AND THE SYSTEM HAS BECOME MORE ORGANIZED
AND SYMMETRICAL. THE INITIAL POSITION IS BASED ON THE MSI
ANIMATION AND ON A NOTCH FEATURE ON A 282057Z SSMIS MICROWAVE
IMAGE. THE INITIAL INTENSITY IS SUPPORTED BY DVORAK ESTIMATES
FROM PGTW, KNES, AND RJTD. UPPER LEVEL ANALYSIS INDICATES THE
SYSTEM IS JUST SOUTH OF THE RIDGE AXIS IN AN AREA OF LOW TO
MODERATE (10-15 KNOT) VERTICAL WIND SHEAR AND GOOD POLEWARD
OUTFLOW. THE CYCLONE IS TRACKING ALONG THE SOUTHERN PERIPHERY
OF A WELL-ESTABLISHED SUBTROPICAL RIDGE TO THE NORTH.
3. FORECAST REASONING:
A. THIS IS THE INITIAL PROGNOSTIC REASONING AND SETS THE
FORECAST PHILOSOPHY.
B. TD 29W WILL PROCEED GENERALLY WESTWARD THROUGHOUT ITS
LIFESPAN, STEERED BY THE STR. FAVORABLE UPPER LEVEL CONDITIONS,
IN ADDITION TO PERENIALLY WARM SEA SURFACE TEMPERATURES IN THE
PHILIPPINE SEA WILL ENSURE STEADY INTENSIFICATION. BY TAU 48,
THE SYSTEM WILL BE AT TYPHOON STRENGTH AND POISED TO CROSS THE
ISLAND OF LUZON. BEFORE TAU 72, 29W WILL EMERGE IN THE SOUTH
CHINA SEA AND REACH A PEAK INTENSITY OF 70 KNOTS.
C. BEYOND TAU 72, THE SYSTEM WILL CROSS HAINAN, CHINA, AND
THE GULF OF TONKIN BEFORE MAKING LANDFALL NEAR HANOI, VIETNAM,
BY TAU 12O. INTERACTION WITH THE TOPOGRAPHY OF HAINAN AND
VIETNAM WILL GRADUALLY ERODE THE SYSTEM. THE LIMITED NUMERIC
MODEL GUIDANCE IS IN TIGHT AGREEMENT - UNUSUAL FOR A DEVELOPING
CYCLONE - BUT, GIVEN THE FORMATIVE STAGE OF THE SYSTEM, THERE
IS LOW CONFIDENCE IN THE JTWC FORECAST. //
NNNN

[stormkite]

This latest image suggests a developing eye at the center of circulation and plenty of low level cloud water in the eye but no deep convection above atm.



IMO at (17.5N 114.4E / 17.5N 112.0E) will be strong.

At about (17.2N 109.5E) wil be Intense





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[euro6208]

Well this is kind of bizarre in that we have a struggling TD unlike the past storms.

[mrbagyo]

the convection of this system is really pathetic as of now... what excites me is the robust pole ward outflow, it resembles typhoon Durian of 2006.

[dexterlabio]

This TD is sure being hurt by the high pressure to its north and the cooler, drier air blowing from it. I am not sure where JTWC is getting the "low to moderate VWS" when wind shear in the area looks kinda unfriendly for consolidation.

If GFS is to be believed, intensification starts just off Northern Luzon and continues to intensify as a typhoon in the SCS.

[euro6208]

This TD is sure being hurt by the high pressure to its north and the cooler, drier air blowing from it. I am not sure where JTWC is getting the "low to moderate VWS" when wind shear in the area looks kinda unfriendly for consolidation.

If GFS is to be believed, intensification starts just off Northern Luzon and continues to intensify as a typhoon in the SCS.

low to moderate shear right over the center circulation as an anticyclone is parked right over it but increases significantly elsewhere...

[euro6208]

WTDN31 PGTW 291500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 29W
(TWENTYNINE) WARNING NR 03//
RMKS//
/1. FOR METEOROLOGISTS
2. 6-HOUR SUMMARY AND ANALYSIS:
TROPICAL DEPRESSION 29W (TWENTYNINE), LOCATED
APPROXIMATELY 634 NM EAST OF MANILA, PHILIPPINES, HAS TRACKED
WESTWARD AT 14 KNOTS OVER THE PAST SIX HOURS. ANIMATED
ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS THE OVERALL
CONVECTION ASSOCIATED WITH THE CONSOLIDATING LOW-LEVEL
CIRCULATION CENTER (LLCC), HAS SLIGHTLY IMPROVED AS FORMATIVE
BANDS HAVE DEEPENED AND ARE WRAPPING TIGHTER INTO THE LLCC.
THE INITIAL POSITION IS BASED ON THE EIR ANIMATION AND
EXTRAPOLATED FROM A 291111Z SSMIS MICROWAVE IMAGE WITH FAIR
CONFIDENCE. THE INITIAL INTENSITY IS HEDGED ON THE HIGH END
OF DVORAK ESTIMATES FROM PGTW AND KNES RANGING FROM 25 TO 30
KNOTS. UPPER LEVEL ANALYSIS INDICATES THE SYSTEM IS JUST SOUTH
OF THE RIDGE AXIS IN AN AREA OF LOW TO MODERATE (10-15 KNOT)
VERTICAL WIND SHEAR AND GOOD POLEWARD OUTFLOW. THE CYCLONE IS
TRACKING ALONG THE SOUTHERN PERIPHERY OF A WELL-ESTABLISHED
SUBTROPICAL RIDGE (STR) TO THE NORTH.
3. FORECAST REASONING:
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE, BUT TRACK SPEEDS HAVE SLIGHTLY
SLOWED AND ARE IN BETTER AGREEMENT WITH THE 29/06Z NAVGEM AND
GFS MODEL FIELDS.
B. TD 29W IS FORECAST TO TRACK GENERALLY WESTWARD, STEERED
BY THE STR, THROUGHOUT ITS LIFESPAN. FAVORABLE UPPER LEVEL
CONDITIONS, IN ADDITION TO PERENNIALLY WARM SEA SURFACE
TEMPERATURES IN THE PHILIPPINE SEA WILL ENSURE STEADY
INTENSIFICATION THROUGH TAU 36. BETWEEN TAU 36 AND TAU 48 THE
SYSTEM SHOULD REACH TYPHOON STRENGTH. BY TAU 48 TD 29W WILL BE
TRACKING OVER THE ISLAND OF LUZON AND WILL SLIGHTLY WEAKEN DUE
TO FRICTIONAL EFFECTS OF LAND. ONCE THE SYSTEM EMERGES IN THE
SOUTH CHINA SEA IT WILL ONCE AGAIN BEGIN TO INTENSIFY AND
REACH A PEAK INTENSITY OF 70 KNOTS BY TAU 72.
C. BEYOND TAU 72, THE SYSTEM WILL CROSS HAINAN, CHINA, AND
THE GULF OF TONKIN BEFORE MAKING LANDFALL NEAR HANOI, VIETNAM,
BY TAU 12O. INTERACTION WITH THE TOPOGRAPHY OF HAINAN AND
VIETNAM WILL GRADUALLY ERODE THE SYSTEM. THOUGH NUMERIC MODEL
GUIDANCE IS LIMITED AT THIS TIME, THE OBJECTIVE AIDS THAT ARE
AVAILABLE ARE IN FAIRLY TIGHT AGREEMENT THROUGH TAU 48, BUT
BEGIN DIVERGE IN POSITION AND TRACK SPEED THEREAFTER. GIVEN
THE FORMATIVE STAGE OF THE SYSTEM AND THE INCREASED UNCERTAINTY
IN THE EXTENDED TAUS, THERE IS LOW CONFIDENCE IN THE JTWC
FORECAST.//
NNNN

[ManilaTC]

and now we have Tropical Storm KROSA.

WTPQ20 RJTD 291800
RSMC TROPICAL CYCLONE ADVISORY
NAME TS 1329 KROSA (1329) UPGRADED FROM TD
ANALYSIS
PSTN 291800UTC 15.7N 131.3E FAIR
MOVE WNW 09KT
PRES 1000HPA
MXWD 035KT
GUST 050KT
30KT 180NM NORTH 120NM SOUTH
FORECAST
24HF 301800UTC 16.0N 125.6E 75NM 70%
MOVE W 14KT
PRES 996HPA
MXWD 040KT
GUST 060KT
48HF 311800UTC 16.7N 119.6E 140NM 70%
MOVE W 15KT
PRES 996HPA
MXWD 040KT
GUST 060KT
72HF 011800UTC 16.9N 114.7E 210NM 70%
MOVE W 12KT
PRES 994HPA
MXWD 040KT
GUST 060KT =

[euro6208]

winds up to 40 knots and forecast to make landfall on halloween as a minimal typhoon.

[dexterlabio]

I'm looking at the visible satloop and for the past few frames it seems it is wrapping up nicely, much better than last night. I agree with JTWC raising the intensity to 40kts. If this keeps up, a minimal Cat1 is likely before touchdown in Luzon, or a Severe TS as per JMA.

[euro6208]

euro wants to strengthen this into a powerful typhoon but weakens it before making a second and third landfall over hainan island/vietnam.