WPAC: BAILU - Tropical Storm

[euro6208]

What a change from EURO.

[wxman57]

Almost all EC ensemble members take it near or over Taiwan and into China. All GFS members take it north to eastern Japan then out to sea to the NE. GFS was dead wrong with Krosa. I'd tend to side with the Euro for this storm.

[euro6208]

97W INVEST
As of 18:00 UTC Aug 20, 2019:

Location: 15.0°N 133.2°E
Maximum Winds: 20 kt
Minimum Central Pressure: 1001 mb

[Hayabusa]

A day since the first TC warning, now Tropical Storm Bailu

TS 1911 (Bailu)
Issued at 07:05 UTC, 21 August 2019

<Analysis at 06 UTC, 21 August>
Scale -
Intensity -
Center position N15°40' (15.7°)
E132°20' (132.3°)
Direction and speed of movement NW 15 km/h (7 kt)
Central pressure 998 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area SW 800 km (425 NM)
NE 190 km (100 NM)

[Nancy Smar]

2019/8/21 07:03:42: [12W Formed] 12W TWELVE 190821 0600 15.2N 131.9E WPAC 25 1001

WTPQ20 RJTD 210600

RSMC TROPICAL CYCLONE ADVISORY

NAME TS 1911 BAILU (1911) UPGRADED FROM TD

ANALYSIS

PSTN 210600UTC 15.7N 132.3E FAIR

MOVE NW 07KT

PRES 998HPA

MXWD 035KT

GUST 050KT

30KT 425NM SOUTHWEST 100NM NORTHEAST

FORECAST

24HF 220600UTC 17.2N 129.0E 50NM 70%

MOVE WNW 09KT

PRES 992HPA

MXWD 045KT

GUST 065KT

48HF 230600UTC 20.1N 126.2E 90NM 70%

MOVE NW 10KT

PRES 990HPA

MXWD 050KT

GUST 070KT

72HF 240600UTC 23.2N 121.9E 140NM 70%

MOVE NW 13KT

PRES 990HPA

MXWD 050KT

GUST 070KT =

[doomhaMwx]

WDPN31 PGTW 210900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 12W (BAILU) WARNING NR 01//
RMKS/

1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 12W (BAILU), LOCATED APPROXIMATELY 716 NM
SOUTH-SOUTHEAST OF KADENA AB, HAS TRACKED NORTHWESTWARD AT 07 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
SHOWS THAT TD 12W HAS A BROAD AREA OF CONVECTION WHICH IS CONTINUING
TO CONSOLIDATE AROUND THE LOW LEVEL CIRCULATION CENTER (LLCC). THE
INITIAL POSITION IS PLACED WITH LOW CONFIDENCE BASED ON THE BROAD
NATURE OF THE SYSTEM. THE POSITION IS BASED ON A PARTIAL 210503Z
AMSR2 89GHZ MICROWAVE IMAGE WHICH SHOWS DEEP CONVECTION TO THE WEST
OF THE LLCC WITH WEAKER BANDING CONVECTION TO THE NORTHWEST AND NORTH
OF THE LLCC. THE INITIAL INTENSITY OF 25 KNOTS IS BASED ON A DVORAK
CURRENT INTENSITY (CI) ESTIMATE OF T1.0 (25 KNOTS) FROM PGTW AND
HEDGED SLIGHTLY BELOW THE CI OF T2.0 (30 KNOTS) FROM RJTD.
ENVIRONMENTAL ANALYSIS SHOWS TD 12W IS EXPERIENCING FAVORABLE
VERTICAL WIND SHEAR (5 TO 15 KNOTS). TD 12W HAS A STRONG EQUATORWARD
OUTFLOW CHANNEL AND A DEVELOPING POLEWARD OUTFLOW CHANNEL WITH A
TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) CELL BEGINNING TO ENHANCE
THE OUTFLOW. SEA SURFACE TEMPERATURES ARE FAVORABLE FOR DEVELOPMENT,
NEAR 30 DEGREES CELSIUS. TD 12W IS TRACKING NORTHWESTWARD WHILE UNDER
THE INFLUENCE OF A SUBTROPICAL RIDGE (STR) LOCATED TO THE NORTHEAST.

3. FORECAST REASONING.
A. THIS IS THE INITIAL PROGNOSTIC REASONING MESSAGE AND SETS THE
FORECAST PHILOSOPHY FOR THIS SYSTEM.
B. IN THE SHORT TERM, TD 12W WILL CONTINUE TO EXPERIENCE FAVORABLE
VERTICAL WIND SHEAR AND REMAIN OVER WARM SEA SURFACE TEMPERATURES,
WHICH WILL ALLOW FOR A STEADY INCREASE IN INTENSITY. THE
AFOREMENTIONED TUTT CELL WILL CONTINUE TO ENHANCE UPPER LEVEL OUTFLOW
IN THE SHORT TERM AND ALSO ALLOW FOR INTENSIFICATION. THE STR TO THE
NORTHEAST WILL REMAIN IN PLACE THROUGH TAU 72 AND ALLOW TD 12W TO
TRACK NORTHWESTWARD. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT,
HOWEVER, DUE TO THE HIGH UNCERTAINTY IN THE INITIAL POSITION THERE IS
LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. AFTER TAU 72, TD 12W WILL CONTINUE TO TRACK NORTHWESTWARD WHILE
UNDER THE INFLUENCE OF THE STR. SHORTLY AFTER TAU 72, TD 12W WILL
MAKE LANDFALL IN CENTRAL TAIWAN WHICH WILL LEAD TO A WEAKENING TREND.
BY TAU 96, AN APPROACHING WEST TO EAST MOVING SHORTWAVE TROUGH WILL
TEMPORARILY WEAKEN THE STR AND ALLOW TD 12W TO TRACK SLIGHTLY MORE
NORTHWARD. LAND INTERACTION WITH CHINA WILL CAUSE TD 12W TO QUICKLY
WEAKEN AFTER TAU 96 AND DISSIPATE BY TAU 120. DYNAMIC MODEL GUIDANCE
IS IN POOR AGREEMENT DURING THIS PORTION OF THE TRACK. MODEL GUIDANCE
HAS A SPREAD OF 860NM BY TAU 120. DUE TO THE MODEL SPREAD AND THE
HIGH UNCERTAINTY IN THE INITIAL POSITION THERE IS LOW CONFIDENCE IN
THIS PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

HWRF again strengthens rapidly...EURO stays constant on a TS making landfall...GFS trending stronger...

[euro6208]

[Hayabusa]

Another large system huh?

TS 1911 (Bailu)
Issued at 12:50 UTC, 21 August 2019

<Analysis at 12 UTC, 21 August>
Scale Large
Intensity -
Center position N15°50' (15.8°)
E130°40' (130.7°)
Direction and speed of movement WNW 15 km/h (9 kt)
Central pressure 998 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area ALL 700 km (375 NM)

[1900hurricane]

This is the replacement name for Haiyan.

[euro6208]

WDPN31 PGTW 212100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 12W (BAILU)
WARNING NR 03//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 12W (BAILU), LOCATED APPROXIMATELY 736 NM
SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED NORTHWESTWARD AT 05 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE
IMAGERY SHOWS CONVECTION CONTINUES TO CONSOLIDATE AROUND THE LOW
LEVEL CIRCULATION CENTER (LLCC) WITH MOST OF THE DEEP CONVECTION
OFFSET TO THE SOUTHWEST. THE INITIAL POSITION IS PLACED WITH LOW
CONFIDENCE BASED ON EIR AND A 211716Z AMSR 37GHZ MICROWAVE IMAGE
WHICH SHOWS BANDING WRAPPING INTO THE LLCC. THE INTENSITY OF 35
KNOTS IS SET BETWEEN DVORAK CURRENT INTENSITY ESTIMATES OF T1.5-2.5
(25-42 KNOTS) AND IS SLIGHTLY ABOVE A 211810Z ADT ESTIMATE OF 33
KNOTS. ENVIRONMENTAL ANALYSIS SHOWS TS 12W IS EXPERIENCING FAVORABLE
VERTICAL WIND SHEAR (5 TO 15 KNOTS). TS 12W HAS A STRONG EQUATORWARD
OUTFLOW CHANNEL, HOWEVER, IT IS SLIGHTLY OFFSET SOUTHWESTWARD FROM
THE CURRENT POSITION. SEA SURFACE TEMPERATURES REMAIN FAVORABLE (28-
29 DEGREES CELSIUS) FOR DEVELOPMENT. TS 12W IS TRACKING
NORTHWESTWARD WHILE UNDER THE INFLUENCE OF A SUBTROPICAL RIDGE (STR)
LOCATED TO THE NORTHEAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE OVERALL FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. IN THE SHORT TERM, TS 12W WILL CONTINUE TO EXPERIENCE
FAVORABLE VERTICAL WIND SHEAR AND WILL REMAIN OVER WARM SEA SURFACE
TEMPERATURES. THESE CONDITIONS WILL ALLOW FOR A STEADY INCREASE IN
INTENSITY, REACHING 55 KNOTS BY TAU 48. THE STR TO THE NORTHEAST
WILL REMAIN IN PLACE THROUGH TAU 72 AND ALLOW TS 12W TO TRACK
NORTHWESTWARD. TS 12W WILL MAKE LANDFALL IN TAIWAN AROUND TAU 60.
PEAK WINDS MAY BE SLIGHTLY HIGHER (65-70 KNOTS) BETWEEN TAU 48 TO
TAU 72 BEFORE TS 12W MAKES LANDFALL IN TAIWAN. DYNAMIC MODEL
GUIDANCE IS IN GOOD AGREEMENT, WITH A SPREAD OF 115NM AT TAU 48,
HOWEVER, DUE TO THE UNCERTAINTY IN THE INITIAL POSITION THERE IS
MODERATE CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. AFTER TAU 72, TS 12W WILL CONTINUE TO TRACK NORTHWESTWARD
WHILE UNDER THE INFLUENCE OF THE STR. BY TAU 72, TS 12W WILL EMERGE
INTO THE TAIWAN STRAIT AND THEN MAKE LANDFALL IN CENTRAL CHINA. LAND
INTERACTION WITH CHINA WILL CAUSE TS 12W TO QUICKLY WEAKEN AFTER
LANDFALL AND DISSIPATE BY TAU 120. DYNAMIC MODEL GUIDANCE IS IN POOR
AGREEMENT DURING THIS PORTION OF THE TRACK, WITH A SPREAD OF 890NM
BY TAU 120. DUE TO THE MODEL SPREAD AND THE HIGH UNCERTAINTY IN THE
INITIAL POSITION THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC
FORECAST TRACK.//
NNNN

[euro6208]

[euro6208]

12W BAILU 190822 0000 16.4N 129.1E WPAC 45 991

[euro6208]

Intensity up now has a strong cat 1 at landfall.

WDPN31 PGTW 220300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 12W (BAILU) WARNING NR
04//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 12W (BAILU), LOCATED APPROXIMATELY 674 NM
SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED WEST-NORTHWESTWARD AT 12
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS CONVECTION CONTINUES TO CONSOLIDATE AROUND THE
LOW LEVEL CIRCULATION CENTER (LLCC) WITH MOST OF THE DEEP CONVECTION
OFFSET TO THE SOUTHWEST. THE INITIAL POSITION IS PLACED WITH LOW
CONFIDENCE BASED ON EIR IMAGERY WHICH SHOWS BANDING WRAPPING INTO THE
LLCC. THE INTENSITY OF 45 KNOTS IS SET ABOVE DVORAK CURRENT INTENSITY
ESTIMATES OF T2.0-2.5 (30-42 KNOTS) AND IS SLIGHTLY ABOVE A 212214Z
SATCON ESTIMATE OF 43 KNOTS. A PARTIAL 210030Z METOP-B ASCAT PASS
SHOWS A SMALL SWATH OF 40-45 KNOT WIND BARBS WITHIN THE SOUTHERN
SEMI-CIRCLE. ENVIRONMENTAL ANALYSIS SHOWS TS 12W IS EXPERIENCING
FAVORABLE VERTICAL WIND SHEAR (5 TO 15 KNOTS). TS 12W HAS A STRONG
EQUATORWARD OUTFLOW CHANNEL AND A TROPICAL UPPER TROPOSPHERIC TROUGH
IS BEGINNING TO ENHANCE POLEWARD OUTFLOW TO THE NORTHEAST. SEA
SURFACE TEMPERATURES REMAIN FAVORABLE (28-29 DEGREES CELSIUS) FOR
DEVELOPMENT. TS 12W IS TRACKING NORTHWESTWARD WHILE UNDER THE
INFLUENCE OF A SUBTROPICAL RIDGE (STR) LOCATED TO THE NORTHEAST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE OVERALL FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. IN THE SHORT TERM, TS 12W WILL CONTINUE TO EXPERIENCE FAVORABLE
VERTICAL WIND SHEAR AND WILL REMAIN OVER WARM SEA SURFACE
TEMPERATURES. THESE CONDITIONS WILL ALLOW FOR A RAPID INCREASE IN
INTENSITY, REACHING 80 KNOTS BY TAU 48. HOWEVER, A POOR UPPER LEVEL
ENVIRONMENT AROUND TAU 48 WILL HINDER FURTHER INTENSIFICATION. THE
STR TO THE NORTHEAST WILL REMAIN IN PLACE THROUGH TAU 72 AND ALLOW TS
12W TO TRACK NORTHWESTWARD. TS 12W WILL MAKE LANDFALL IN TAIWAN
AROUND TAU 60. DYNAMIC MODEL GUIDANCE IS IN GOOD AGREEMENT, WITH A
SPREAD OF 110NM AT TAU 48; HOWEVER, DUE TO THE UNCERTAINTY IN THE
INITIAL POSITION THERE IS MODERATE CONFIDENCE IN THIS PORTION OF THE
JTWC FORECAST TRACK.
C. AFTER TAU 72, TS 12W WILL CONTINUE TO TRACK NORTHWESTWARD WHILE
UNDER THE INFLUENCE OF THE STR. BY TAU 72, TS 12W WILL EMERGE INTO
THE TAIWAN STRAIT AND THEN MAKE LANDFALL IN CENTRAL CHINA. LAND
INTERACTION WITH CHINA WILL CAUSE TS 12W TO WEAKEN QUICKLY AFTER
LANDFALL AND WILL DISSIPATE BY TAU 120. DYNAMIC MODEL GUIDANCE IS IN
POOR AGREEMENT DURING THIS PORTION OF THE FORECAST DUE TO A
BIFURCATION IN MODEL GUIDANCE. THE JTWC TRACK IS IN AGREEMENT WITH A
WEST-NORTHWESTERN PATH SOUTH OF THE STR AND IS NOT EXPECTED TO
RECURVE, AS SEEN IN THE ECMWF AND UKMET TRACKS. DUE TO THE MODEL
SPREAD AND THE HIGH UNCERTAINTY IN THE INITIAL POSITION THERE IS LOW
CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[doomhaMwx]

Lol. The GFS is the most southerly outlier among the model guidance right now, that it even has Bailu eventually making landfall near HongKong, but almost all its ensemble members actually take the storm over Taiwan.

[doomhaMwx]

The circulation still appears to be elongated on the latest ASCAT pass.

[Hayabusa]

Severe Tropical Storm

STS 1911 (Bailu)
Issued at 18:45 UTC, 22 August 2019

<Analysis at 18 UTC, 22 August>
Scale Large
Intensity -
Center position N17°10' (17.2°)
E127°20' (127.3°)
Direction and speed of movement NNW 20 km/h (11 kt)
Central pressure 985 hPa
Maximum sustained wind speed 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
≥ 30 kt wind area NE 750 km (400 NM)
SW 440 km (240 NM)

[Hayabusa]

Bailu has shear on its side yet it is struggling. Lekima is questioning itself...

[doomhaMwx]

Nearing landfall.

[doomhaMwx]

Basco station in Batanes recorded sustained winds of 72kph and a SLP of 987.5 mb early in the morning (PhT).