WPAC: BAVI - Tropical Storm: Discussion

[Crostorm]

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

----- Current Analysis -----
Date : 19 OCT 2008 Time : 003000 UTC
Lat : 25:18:55 N Lon : 148:05:55 E


CI# /Pressure/ Vmax
3.3 / 986.8mb/ 51.0kt


Final T# Adj T# Raw T#
(3hr avg)
3.3 3.6 3.7

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -52.4C Cloud Region Temp : -49.8C

Scene Type : CURVED BAND with 0.88 ARC in LT GRAY

Positioning Method : FORECAST INTERPOLATION

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

Tno/CI Rules : Constraint Limits : 0.2T/hour
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[Chacor]

Named.

WTPQ20 RJTD 190600
RSMC TROPICAL CYCLONE ADVISORY
NAME TS 0818 BAVI (0818) UPGRADED FROM TD
ANALYSIS
PSTN 190600UTC 26.6N 148.4E FAIR
MOVE N 12KT
PRES 1000HPA
MXWD 035KT
GUST 050KT
30KT 90NM
FORECAST
24HF 200600UTC 34.7N 150.4E 120NM 70%
MOVE N 21KT
PRES 992HPA
MXWD 045KT
GUST 065KT
48HF 210600UTC 40.6N 158.2E 200NM 70% EXTRATROPICAL LOW =

[Chacor]

Look at those low clouds ahead of Bavi. Not long before extratropicality sets in, but for now pretty decent shape and convection.

[Chacor]

WTPQ20 RJTD 191200
RSMC TROPICAL CYCLONE ADVISORY
NAME TS 0818 BAVI (0818)
ANALYSIS
PSTN 191200UTC 28.4N 149.2E FAIR
MOVE NNE 19KT
PRES 998HPA
MXWD 035KT
GUST 050KT
30KT 140NM EAST 60NM WEST
FORECAST
24HF 201200UTC 36.6N 153.0E 85NM 70%
MOVE NNE 22KT
PRES 990HPA
MXWD 045KT
GUST 065KT
48HF 211200UTC 42.0N 163.7E 180NM 70% EXTRATROPICAL LOW =

[HURAKAN]

Old image:



I think that the intensity of this system may be being underestimated like with many small systems.

Now:

[Chacor]

Is there still a need to refer to it as TC 23W in the title? 23W isn't even official, and it has a name now after all.

[HURAKAN]

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

----- Current Analysis -----
Date : 19 OCT 2008 Time : 130000 UTC
Lat : 28:53:06 N Lon : 149:27:30 E

CI# /Pressure/ Vmax
3.8 / 979.2mb/ 61.0kt

Final T# Adj T# Raw T#
(3hr avg)
3.6 3.6 3.6

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -73.2C Cloud Region Temp : -72.2C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

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

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

[HURAKAN]

[HURAKAN]

Bavi looks very similar to Chantal 2007.

Bavi:



Chantal:

[Chacor]

The difference being the centre of Bavi is firmly under deep convection.

[HURAKAN]

The difference being the centre of Bavi is firmly under deep convection.

I agree and that's why I suspect the intensity is quite higher.

[HURAKAN]

Latest Dvorak:

19/1430 UTC 29.6N 149.8E T3.5/3.5 BAVI -- West Pacific Ocean

[HURAKAN]

[Chacor]

WTPQ20 RJTD 192100
RSMC TROPICAL CYCLONE ADVISORY
NAME TS 0818 BAVI (0818)
ANALYSIS
PSTN 192100UTC 31.4N 151.4E FAIR
MOVE NE 25KT
PRES 992HPA
MXWD 045KT
GUST 065KT
30KT 160NM EAST 80NM WEST
FORECAST
24HF 202100UTC 38.4N 155.9E 85NM 70% EXTRATROPICAL LOW =

[Chacor]

WTPQ20 RJTD 200000
RSMC TROPICAL CYCLONE ADVISORY
NAME TS 0818 BAVI (0818)
ANALYSIS
PSTN 200000UTC 32.6N 152.0E FAIR
MOVE NE 25KT
PRES 992HPA
MXWD 045KT
GUST 065KT
30KT 160NM EAST 80NM WEST
FORECAST
24HF 210000UTC 40.5N 157.0E 85NM 70% EXTRATROPICAL LOW =

[HurricaneBill]

Bavi's only the 18th named storm this year. Normally there'd be about 22 named storms in the WPAC by this point of the year.

[HURAKAN]

WTPN31 PGTW 200300
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL STORM 23W (BAVI) WARNING NR 006
01 ACTIVE TROPICAL CYCLONE IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
200000Z --- NEAR 32.4N 152.1E
MOVEMENT PAST SIX HOURS - 030 DEGREES AT 26 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
070 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
REPEAT POSIT: 32.4N 152.1E
---
FORECASTS:
12 HRS, VALID AT:
201200Z --- 36.4N 155.2E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
VECTOR TO 24 HR POSIT: 045 DEG/ 26 KTS
---
24 HRS, VALID AT:
210000Z --- 40.1N 160.0E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
EXTRATROPICAL
---
REMARKS:
200300Z POSITION NEAR 33.4N 152.9E.
TROPICAL STORM (TS) 23W (BAVI) LOCATED APPROXIMATELY 595 NM
NORTHEAST OF CHICHI JIMA, HAS TRACKED NORTH-NORTHEASTWARD AT
26 KNOTS OVER THE PAST SIX HOURS. RECENT ANIMATED MULTISPECTRAL
SATELLITE IMAGERY INDICATES A RAPIDLY TRANSITIONING EXTRA-
TROPICAL SYSTEM MOVING EXPEDITIOUSLY NORTH-NORTHEASTWARD ALONG
THE NORTHWESTERN PERIPHERY OF THE LOW TO MID-LEVEL SUBTROPICAL
RIDGE. A DISTINCT CENTRAL DENSE OVERCAST FEATURE HAS BEGUN TO
DISTORT PREFERENTIALLY TOWARDS THE NORTHEAST WITH STRATIFORM
CLOUDS WRAPPING INTO THE SYSTEM FROM THE SOUTHWESTERN QUADRANT
AHEAD OF A FAST-APPROACHING COLD FRONT. THE STORM IS FORECAST
TO INTENSIFY SLIGHTLY UNDER INCREASED UPPER LEVEL DIVERGENT FLOW
AHEAD OF THE FRONT. ALL THE WHILE TS 23W WILL CONTINUE TO
ACCELERATE TOWARDS THE NORTHEAST AND WILL COMPLETE EXTRATROPICAL
TRANSITION WITHIN 12 HOURS. THIS IS THE FINAL WARNING ON THIS
SYSTEM BY THE JOINT TYPHOON WARNING CENTER (NAVMARFCSTCEN). THE
SYSTEM WILL BE CLOSELY MONITORED FOR SIGNS OF REGENERATION.
MAXIMUM SIGNIFICANT WAVE HEIGHT AT 200000Z IS 12 FEET.

Bye say JTWC!

[Chacor]

Almost nothing left of Bavi, just one big extratropical-looking band.

[Chacor]

Dead.

WTPQ20 RJTD 201200
RSMC TROPICAL CYCLONE ADVISORY
NAME DEVELOPING LOW FORMER TS 0818 BAVI (0818)
ANALYSIS
PSTN 201200UTC 38N 154E
MOVE N 25KT
PRES 990HPA
MXWD 050KT
30KT 600NM =