WPAC : TROPICAL STORM CHOI-WAN (15W)

[HURAKAN]

Looking good

[cycloneye]

Impressive ring around that pinhole eye.

[cycloneye]

1500z Advisory from JWTC=90kts

WTPN31 PGTW 141500
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TYPHOON 15W (CHOI-WAN) WARNING NR 011
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
141200Z --- NEAR 16.0N 147.5E
MOVEMENT PAST SIX HOURS - 305 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.0N 147.5E
---
FORECASTS:
12 HRS, VALID AT:
150000Z --- 16.8N 146.6E
MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
100 NM SOUTHWEST QUADRANT
110 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 305 DEG/ 08 KTS
---
24 HRS, VALID AT:
151200Z --- 17.8N 145.2E
MAX SUSTAINED WINDS - 110 KT, GUSTS 135 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
050 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
125 NM SOUTHEAST QUADRANT
110 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 300 DEG/ 09 KTS
---
36 HRS, VALID AT:
160000Z --- 18.7N 143.6E
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
125 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 310 DEG/ 09 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
161200Z --- 19.8N 142.1E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 320 DEG/ 07 KTS
---
72 HRS, VALID AT:
171200Z --- 21.8N 140.2E
MAX SUSTAINED WINDS - 125 KT, GUSTS 150 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 140 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
125 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 350 DEG/ 08 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
181200Z --- 24.9N 139.5E
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 020 DEG/ 10 KTS
---
120 HRS, VALID AT:
191200Z --- 28.8N 141.2E
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
141500Z POSITION NEAR 16.2N 147.3E.
TYPHOON (TY) 15W (CHOI-WAN), LOCATED APPROXIMATELY 105 NM EAST-
NORTHEAST OF SAIPAN, HAS TRACKED NORTHWESTWARD AT 04 KNOTS AND
RAPIDLY DEEPENED OVER THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 141200Z IS 29 FEET. NEXT WARNINGS AT 142100Z, 150300Z,
150900Z AND 151500Z. REFER TO TROPICAL STORM 16W (KOPPU) WARNINGS
(WTPN32 PGTW) FOR SIX-HOURLY UPDATES.//
NNNN

[HURAKAN]

Looks like Choi-wan is laughing at the 90 knots!

[Macrocane]

Looks like Choi-wan is laughing at the 90 knots!

Yes it is, like Koppu is laughing at the 60 kt. This is a very impressive cyclone, it seems that Jimena could lose the throne as the strongest tropical cyclone so far this year.

[HURAKAN]

14/1430 UTC 16.4N 147.3E T5.5/5.5 CHOI-WAN -- West Pacific

102 knots says Dvorak.

[cycloneye]

ADT numbers are even more stronger.

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 14 SEP 2009 Time : 153000 UTC
Lat : 16:22:59 N Lon : 147:06:31 E


CI# /Pressure/ Vmax
6.1 / 926.8mb/117.4kt

Final T# Adj T# Raw T#
(3hr avg)
6.1 6.2 6.6

Latitude bias adjustment to MSLP : +2.4mb

Estimated radius of max. wind based on IR :N/A km

Center Temp : -39.8C Cloud Region Temp : -79.2C

Scene Type : EYE

Positioning Method : SPIRAL ANALYSIS

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : 2.2T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

Most agencies agree.

[P.K.]

RSMC Tokyo now have this listed as T6.0 so they'll be increasing the current 75kts shortly.

[P.K.]

WTPQ20 RJTD 141800
RSMC TROPICAL CYCLONE ADVISORY
NAME TY 0914 CHOI-WAN (0914)
ANALYSIS
PSTN 141800UTC 16.6N 147.0E GOOD
MOVE WNW SLOWLY
PRES 945HPA
MXWD 085KT
GUST 120KT
50KT 100NM
30KT 280NM EAST 220NM WEST
FORECAST
24HF 151800UTC 18.4N 144.5E 70NM 70%
MOVE NW 07KT
PRES 935HPA
MXWD 090KT
GUST 130KT
48HF 161800UTC 20.1N 141.2E 110NM 70%
MOVE WNW 09KT
PRES 935HPA
MXWD 090KT
GUST 130KT
72HF 171800UTC 22.3N 138.8E 160NM 70%
MOVE NW 08KT
PRES 935HPA
MXWD 090KT
GUST 130KT =

[HURAKAN]

NRL: 120 knots

That's sounds more like it!

[bombarderoazul]

Looks like its well on its way to cat 5 status.

[cycloneye]

Forecast to become a Super-Typhoon.

2100z Advisory from JTWC=120kts

PGTW 142100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TYPHOON 15W (CHOI-WAN) WARNING NR 012
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
141800Z --- NEAR 16.6N 147.1E
MOVEMENT PAST SIX HOURS - 315 DEGREES AT 06 KTS
POSITION ACCURATE TO WITHIN 025 NM
POSITION BASED ON EYE FIXED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.6N 147.1E
---
FORECASTS:
12 HRS, VALID AT:
150600Z --- 17.6N 146.0E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
050 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
105 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 310 DEG/ 08 KTS
---
24 HRS, VALID AT:
151800Z --- 18.7N 144.7E
MAX SUSTAINED WINDS - 135 KT, GUSTS 165 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
060 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
115 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 305 DEG/ 09 KTS
---
36 HRS, VALID AT:
160600Z --- 19.7N 143.2E
MAX SUSTAINED WINDS - 135 KT, GUSTS 165 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 310 DEG/ 08 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
161800Z --- 20.8N 141.9E
MAX SUSTAINED WINDS - 140 KT, GUSTS 170 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
040 NM SOUTHEAST QUADRANT
040 NM SOUTHWEST QUADRANT
040 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
065 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
130 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
130 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 330 DEG/ 07 KTS
---
72 HRS, VALID AT:
171800Z --- 23.4N 140.4E
MAX SUSTAINED WINDS - 140 KT, GUSTS 170 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 135 NM NORTHEAST QUADRANT
135 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
135 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 010 DEG/ 07 KTS
---
LONG RANGE OUTLOOK:
NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 250 NM
ON DAY 4 AND 350 NM ON DAY 5... AND FOR INTENSITY
NEAR 20 KT EACH DAY.
---
96 HRS, VALID AT:
181800Z --- 26.1N 140.8E
MAX SUSTAINED WINDS - 130 KT, GUSTS 160 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 025 DEG/ 11 KTS
---
120 HRS, VALID AT:
191800Z --- 30.0N 143.1E
MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
142100Z POSITION NEAR 16.9N 146.8E. TYPHOON (TY) 15W (CHOI-WAN),
LOCATED APPROXIMATELY 110 NM NORTHEAST OF SAIPAN, HAS TRACKED
NORTHWESTWARD AT 06 KNOTS OVER THE LAST 06 HOURS. ANIMATED INFRARED
IMAGERY SHOWS A BROAD SYSTEM WITH A WELL DEFINED EYE AND DEEP
CONVECTIVE BANDS WRAPPING INTO THE CENTER. ANIMATED WATER VAPOR
IMAGERY SHOWS A TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) TO THE
NORTHEAST THAT IS PROVIDING A DEFINED OUTFLOW CHANNEL TO THE EAST IN
ADDITION TO BROAD OUTFLOW TO THE EAST AND SOUTH. UPPER LEVEL
ANALYSIS INDICATES THAT THE SYSTEM IS LOCATED UNDER A SMALL UPPER-
LEVEL ANTI-CYCLONE THAT IS PROVIDING THE BROAD OUTFLOW. THE SYSTEM
IS LOCATED IN AN AREA OF VERY HIGH SEA SURFACE TEMPERATURES (SST)
AND LOW VERTICAL WIND SHEAR. THESE ENVIRONMENTAL FACTORS, ALONG WITH
THE OUTFLOW CHANNEL BECOMING ESTABLISHED INTO THE TUTT, HAVE LED TO
RAPID INTENSIFICATION OF THE SYSTEM OVER THE LAST 12 HOURS, A TREND
THAT IS EXPECTED TO CONTINUE FOR ANOTHER 06 HOURS UNTIL THE HIGH SST
STARTS TO DECREASE. CURRENTLY THE SYSTEM IS IN A WEAK STEERING
ENVIRONMENT AND UNDER THE INFLUENCE OF THE LOW- TO MID-LEVEL
SUBTROPICAL RIDGE (STR) LOCATED TO THE FAR NORTHEAST. THE SYSTEM IS
STILL EXPECTED TO CONTINUE TO SLOWLY TRACK TO THE NORTHWEST AND
RECURVE AROUND THE WESTERN PERIPHERY OF THE STR BETWEEN TAU 48 AND
72 IN CONJUNCTION WITH THE PASSAGE OF A MIDLATITUDE TROUGH. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 141800Z IS 30 FEET. NEXT WARNINGS AT
150300Z, 150900Z, 151500Z AND 152100Z. REFER TO TYPHOON 16W (KOPPU)
WARNINGS (WTPN32 PGTW) FOR SIX-HOURLY UPDATES.
//
NNNN

[CrazyC83]

Not just a Super Typhoon, but Category 5 in the forecast...

Seems reasonable, although I would go with 125 kt right now, with a pressure guess of 930mb.

[CrazyC83]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 14 SEP 2009 Time : 200000 UTC
Lat : 16:44:55 N Lon : 146:57:19 E


CI# /Pressure/ Vmax
6.5 / 916.3mb/127.0kt


Final T# Adj T# Raw T#
(3hr avg)
6.5 6.6 6.6

Latitude bias adjustment to MSLP : +2.3mb

Estimated radius of max. wind based on IR : 15 km

Center Temp : -6.7C Cloud Region Temp : -75.7C

Scene Type : EYE

Positioning Method : RING/SPIRAL COMBINATION

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

Finally a classic WPAC typhoon

[StormingB81]

Looks like we can breathe easy in Japan this thing isnt comming!!!!

[somethingfunny]

Finally a classic WPAC typhoon

Oh my.

[HURAKAN]

First visible!

[somethingfunny]

Looks like we can breathe easy in Japan this thing isnt comming!!!!

What part of Japan are you in that you're breathing easily? I see a large area of Japan is within the cone of uncertainty right now.



It will depend on the timing and strength of the Subtropical Ridge and the incoming trough, and clearly JTWC still sees a possibility that the recurve could be delayed long enough for Choi-Wan to landfall in the Kanto region of Japan including Tokyo/Yokohama. Even if that doesn't happen, Choi-Wan is growing more powerful by the hour and will likely increase in size substantially, especially if it undergoes an eyewall replacement cycle and even moreso when it begins interacting with the trough. There's a very high probability that eastern Japan will be impacted by heavy rain and waves from the outer bands at the very least. Remember that Etau, a much weaker storm earlier this season that also stayed offshore, killed about a dozen people due to flooding. And the main point is that the official forecast does NOT place Japan in the clear yet.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.