WPAC: BARIJAT - Tropical Storm

[euro6208]

WDPN32 PGTW 100300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 27W (TWENTYSEVEN)
WARNING NR 02//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 27W (TWENTYSEVEN), LOCATED APPROXIMATELY
210 NM SOUTH OF TAIPEI, TAIWAN, HAS TRACKED WEST-SOUTHWESTWARD AT 08
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS AN EXPOSED, DEFINED LOW-LEVEL CIRCULATION CENTER
(LLCC) WITH IMPROVED DEEP CONVECTIVE BANDING OVER THE SOUTHERN
SEMICIRCLE. A 092158Z WINDSAT 37GHZ IMAGE AND ANIMATED RADAR IMAGERY
FROM THE TAIWAN RADAR REVEAL AN ORGANIZED LLCC WITH NARROW BANDING
WRAPPING INTO A DEFINED CENTER, WHICH SUPPORTS THE CURRENT POSITION
WITH GOOD CONFIDENCE. THE CURRENT INTENSITY IS ASSESSED AT 30 KNOTS
BASED ON A PGTW DVORAK INTENSITY ESTIMATE OF T2.0 (30 KNOTS).
ADDITIONALLY, A 09/21Z SURFACE OBSERVATION FROM LAN YU (59567),
APPROXIMATELY 60NM WEST-NORTHWEST OF THE 09/21Z POSITION, INDICATES
10-MINUTE MEAN SURFACE WINDS AT 040/33 KNOTS AND SLP NEAR 1005.3MB.
UPPER-LEVEL ANALYSIS INDICATES A MARGINALLY FAVORABLE ENVIRONMENT
WITH MODERATE NORTHERLY VERTICAL WIND SHEAR (VWS) OFFSET BY
DIFFLUENT EQUATORWARD OUTFLOW. FURTHERMORE, SST (29-30C) AND OCEAN
HEAT CONTENT VALUES ARE CONDUCIVE FOR FURTHER DEVELOPMENT. TD 27W IS
TRACKING WEST-SOUTHWESTWARD UNDER THE STEERING INFLUENCE OF A LOW-
TO MID-LEVEL SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY FROM THE
PREVIOUS WARNING.
B. TD 27W SHOULD CONTINUE TRACKING WESTWARD TO WEST-SOUTHWESTWARD
THROUGH TAU 72 WITH A SLOW INTENSIFICATION TREND AND PEAK INTENSITY
OF 40 KNOTS AT TAU 36 AS VWS RELAXES. NUMERICAL MODEL GUIDANCE IS IN
FAIR AGREEMENT AND SUPPORTS THE TRACK OVER WATER TOWARD HONG KONG.
C. AFTER TAU 72, THE SYSTEM IS FORECASTED TO GRADUALLY WEAKEN DUE
TO INTERACTION WITH LAND AND IS EXPECTED TO DISSIPATE AS IT TRACKS
OVER NORTHERN VIETNAM AFTER TAU 96. NUMERICAL MODEL GUIDANCE REMAINS
IN FAIR AGREEMENT, THEREFORE, THERE IS LOW OVERALL CONFIDENCE IN THE
JTWC FORECAST TRACK, WHICH IS POSITIONED CLOSE TO THE MULTI-MODEL
CONSENSUS.//
NNNN

[euro6208]

[euro6208]

Upgraded to Tropical Storm 27W.

WDPN32 PGTW 101500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 27W (TWENTYSEVEN)
WARNING NR 04//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 27W (TWENTYSEVEN), LOCATED APPROXIMATELY 225
NM SOUTH OF TAIPEI, TAIWAN, HAS TRACKED WEST-SOUTHWESTWARD AT 06
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY SHOWS A SMALL, SLOWLY CONSOLIDATING SYSTEM WITH FLARING
CENTRAL CONVECTION AND SHALLOW FORMATIVE BANDS LOOSELY WRAPPING INTO
AN OBSCURED LOW LEVEL CIRCULATION (LLC). THE INITIAL POSITION IS
PLACED WITH BETTER CONFIDENCE USING A COMPOSITE RADAR LOOP FROM
TAIWAN CENTRAL WEATHER BUREAU THAT SHOWS A RAGGED LLC FEATURE THAT
HAS SHRUNK IN DIAMETER. THIS LLC ALSO LINED UP WELL WITH A PARTIALLY
OBSCURED BUT DISCERNIBLE MICROWAVE LLC FEATURE ON THE 101038Z 91 GHZ
SSMIS PASS. THE INITIAL INTENSITY OF 35 KNOTS IS BASED ON THE PGTW
DVORAK INTENSITY ESTIMATE OF T2.5 AND IS SUPPORTED BY NEARBY SURFACE
OBSERVATIONS. UPPER-LEVEL ANALYSIS INDICATES A MARGINALLY FAVORABLE
ENVIRONMENT WITH MODERATE NORTHEASTERLY VERTICAL WIND SHEAR (VWS)
PARTLY OFFSET BY A SOLID EQUATORWARD OUTFLOW. SST (29-30C) AND OCEAN
HEAT CONTENT ARE CONDUCIVE. THE CYCLONE IS TRACKING UNDER THE
STEERING INFLUENCE OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) TO
THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY FROM THE
PREVIOUS WARNING.
B. TS 27W SHOULD CONTINUE TRACKING WEST-SOUTHWESTWARD THROUGH TAU
72 WITH A SLOW INTENSIFICATION RATE, PEAKING AT 45 KNOTS BY TAU 48.
BEFORE TAU 72, THE CYCLONE WILL MAKE LANDFALL OVER THE LUICHOW
PENINSULA, CHINA. NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT;
HOWEVER, GIVEN THE FORMATIVE NATURE OF THE SYSTEM, THERE IS LOW
CONFIDENCE IN THIS PORTION OF THE TRACK FORECAST.
C. AFTER TAU 72, TS 27W WILL CONTINUE ON A MORE WESTWARD TRACK AND
CROSS THE GULF OF TONKIN, MAKING A FINAL LANDFALL OVER NORTHERN
VIETNAM JUST EAST OF HANOI. DUE TO INTERACTION WITH LAND AND
INCREASING VWS, THE SYSTEM WILL ERODE AND DISSIPATE BY TAU 96 AS IT
TRACKS FURTHER INLAND. NUMERICAL MODEL GUIDANCE SIGNIFICANTLY
SPREADS, ALSO LENDING LOW CONFIDENCE IN THE EXTENDED PORTION OF THE
JTWC FORECAST TRACK.//
NNNN

[kala]

JMA has named it Barijat. First use of this name, replacing 2013's Utor.

[doomhaMwx]

TS 1823 (Barijat)
Issued at 10:00 UTC, 11 September 2018

<Analysis at 09 UTC, 11 September>
Scale -
Intensity -
Center position N20°35' (20.6°)
E117°40' (117.7°)
Direction and speed of movement W 20 km/h (10 kt)
Central pressure 998 hPa
Maximum wind speed near center 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
≥ 30 kt wind area ALL 170 km (90 NM)

<Forecast for 21 UTC, 11 September>
Intensity -
Center position of probability circle N20°30' (20.5°)
E116°00' (116.0°)
Direction and speed of movement W 15 km/h (8 kt)
Central pressure 994 hPa
Maximum wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
Radius of probability circle 60 km (30 NM)

<Forecast for 09 UTC, 12 September>
Intensity -
Center position of probability circle N20°30' (20.5°)
E114°10' (114.2°)
Direction and speed of movement W 15 km/h (8 kt)
Central pressure 992 hPa
Maximum wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
Radius of probability circle 90 km (50 NM)

<Forecast for 06 UTC, 13 September>
Intensity -
Center position of probability circle N20°35' (20.6°)
E110°00' (110.0°)
Direction and speed of movement W 20 km/h (10 kt)
Central pressure 992 hPa
Maximum wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
Radius of probability circle 180 km (95 NM)

<Forecast for 06 UTC, 14 September>
Intensity -
Center position of probability circle N21°10' (21.2°)
E105°00' (105.0°)
Direction and speed of movement W 20 km/h (12 kt)
Central pressure 1000 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 260 km (140 NM)

[euro6208]

WDPN32 PGTW 120900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 27W (BARIJAT) WARNING
NR 11//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 27W (BARIJAT), LOCATED APPROXIMATELY 86 NM
SOUTH OF HONG KONG, HAS TRACKED WESTWARD AT 10 KNOTS OVER THE PAST
SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS
FLARING CONVECTION TO SOUTHWEST OF A PARTIALLY EXPOSED LOW LEVEL
CIRCULATION. THE INITIAL POSITION IS PLACED WITH FAIR CONFIDENCE
USING THE MSI IMAGERY AND EXTRAPOLATED FROM A 120225Z ASCAT DIRECT
PASS. THE INITIAL INTENSITY OF 40 KNOTS IS AVERAGED BETWEEN RJTD AND
PGTW DVORAK INTENSITY ESTIMATES OF T2.5 AND T3.0 (35-45 KTS) AND
SUPPORTED BY THE ASCAT PASS. THE
ENVIRONMENT IS MARGINALLY FAVORABLE WITH MODERATE (15-20 KT)
NORTHERLY VERTICAL WIND SHEAR (VWS), GOOD EQUATORWARD OUTFLOW, AND
WARM SEA SURFACE TEMPERATURES OF ABOUT 29 CELSIUS. THE CYCLONE IS
TRACKING ALONG THE SOUTHERN PERIPHERY OF A SHALLOW SUBTROPICAL RIDGE
(STR).
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY FROM THE
PREVIOUS WARNING.
B. FOR THE DURATION OF THE FORECAST, TS 27W WILL CONTINUE ON A
WESTWARD TRACK UNDER THE STR, CROSSING THE LEIZHOU PENINSULA AND
STRADDLING THE SOUTH CHINA COAST BEFORE MAKING LANDFALL OVER NORTHERN
VIETNAM NEAR THE CHINESE BORDER. INCREASED LAND INTERACTION WILL
BEGIN A GRADUAL WEAKENING TREND, LEADING TO DISSIPATION BY TAU 36
AFTER LANDFALL. THE JTWC FORECAST TRACK CLOSELY FOLLOWS THE CONSENSUS
WITH LOW CONFIDENCE DUE TO HIGH SPREAD IN THE NUMERICAL MODEL
GUIDANCE.//
NNNN

[euro6208]

WDPN32 PGTW 130900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 27W (BARIJAT)
WARNING
NR 15//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 27W (BARIJAT), LOCATED APPROXIMATELY 207 NM
EAST OF HANOI, VIETNAM, HAS TRACKED WESTWARD AT 09 KNOTS OVER THE
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS
WEAK CONVECTION BEING SHEARED AWAY FROM AN EXPOSED LOW LEVEL
CIRCULATION CENTER. THE INITIAL POSITION IS PLACED WITH LOW
CONFIDENCE BASED ON THE MSI IMAGERY, WHERE LOW-LEVEL FEATURES ARE
OBSCURED BY MID-LEVEL TURNING AND REMNANT CIRRUS. THE INITIAL
INTENSITY IS ASSESSED AT 30 KNOTS, UNDER THE DVORAK CURRENT
INTENSITY ESTIMATE OF T2.5 (35 KNOTS) FROM PGTW BUT IN AGREEMENT
WITH THE RJTD ESTIMATE OF T2.0 (30 KTS), BASED ON THE WEAKENING
CONVECTION AND RISING PRESSURE IN OBSERVATIONS. OBSERVATIONS FROM
BEIHAI AIRPORT, CHINA, 33NM NORTHWEST OF THE CENTER, REPORT ONLY 4
KT WINDS AND 1004MB MSLP. 27W HAS TRACKED OVER THE LEIZHOU PENINSULA
OVER THE LAST SIX HOURS AND WEAKENED DUE TO LAND INTERACTION,
MODERATE (20 KT) VERTICAL WIND SHEAR, AND LIMITED OUTFLOW DUE TO
NORTHEASTERLY FLOW ALOFT IMPINGING ON THE SYSTEM. TD 27W IS TRACKING
WESTWARD UNDER THE SOUTHERN PERIPHERY OF THE LOW- TO MID-LEVEL
SUBTROPICAL RIDGE (STR) SITUATED OVER SOUTHERN CHINA.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TD 27W WILL CONTINUE TO TRACK WESTWARD OVER THE GULF OF TONKIN
AND THEN MAKE LANDFALL OVER VIETNAM JUST BEFORE TAU 12 WITH
DISSIPATION EXPECTED BY TAU 36. TD 27W MAY INTENSIFY SLIGHTLY
BETWEEN TAU 0 AND TAU 12 OVER THE GULF OF TONKIN DUE TO THE WARM SEA
SURFACE TEMPERATURES (29 CELSIUS) IN THE GULF OF TONKIN. HOWEVER,
MARGINAL ENVIRONMENTAL CONDITIONS INCLUDING WEAK DIFFLUENCE ALOFT,
MODERATE VWS, LAND INTERACTION, AND DRY AIR ENTRAINMENT ARE EXPECTED
TO LIMIT INTENSIFICATION. THERE IS HIGH CONFIDENCE IN THE JTWC
FORECAST TRACK, WHICH CLOSELY FOLLOWS THE MULTI-MODEL CONSENSUS.//
NNNN

[doomhaMwx]

Heh, this really got overshadowed by Mangkhut.

TD
Issued at 06:45 UTC, 13 September 2018

<Analysis at 06 UTC, 13 September>
Scale -
Intensity -
TD
Center position N20°00' (20.0°)
E108°00' (108.0°)
Direction and speed of movement W 20 km/h (10 kt)
Central pressure 1004 hPa

[euro6208]

WTPN32 PGTW 132100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL DEPRESSION 27W (BARIJAT) WARNING NR 017
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
131800Z --- NEAR 21.7N 107.2E
MOVEMENT PAST SIX HOURS - 290 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY A COMBINATION OF
SATELLITE AND SYNOPTIC DATA
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 020 KT, GUSTS 030 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
REPEAT POSIT: 21.7N 107.2E
---
FORECASTS:
12 HRS, VALID AT:
140600Z --- 22.1N 105.0E
MAX SUSTAINED WINDS - 015 KT, GUSTS 025 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
VECTOR TO 24 HR POSIT: 290 DEG/ 10 KTS
---
24 HRS, VALID AT:
141800Z --- 22.7N 103.0E
MAX SUSTAINED WINDS - 015 KT, GUSTS 025 KT
WIND RADII VALID OVER OPEN WATER ONLY
DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND
---
REMARKS:
132100Z POSITION NEAR 21.8N 106.7E.
TROPICAL DEPRESSION (TD) 27W (BARIJAT), LOCATED APPROXIMATELY 84 NM
EAST-NORTHEAST OF HANOI, VIETNAM, HAS TRACKED WEST-NORTHWESTWARD
AT 09 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
(EIR) SATELLITE IMAGERY DEPICTS A RAPIDLY WEAKENING, EXPOSED LOW-
LEVEL CIRCULATION CENTER WITH NO SIGNIFICANT DEEP CONVECTION. THE
CURRENT POSITION IS BASED ON THE EIR IMAGERY AS WELL AS SURFACE
OBSERVATIONS FROM MONG CAI (48838), LANG SON (48830) AND QINZHOU
(59632), WHICH REPORTED WINDS LESS THAN 10 KNOTS AND SLP NEAR
1009MB. THE CURRENT INTENSITY IS CONSERVATIVELY ASSESSED AT 25
KNOTS, HOWEVER, TD 27W IS EXPECTED TO DISSIPATE QUICKLY WITHIN THE
NEXT 12 HOURS AS IT TRACKS INLAND. THE MAJORITY OF THE MODELS HAVE
LOST THE SYSTEM DUE TO ITS WEAK NATURE BUT LIMITED MODELS DEPICT A
GENERALLY WEST-NORTHWESTWARD TRACK THROUGH THE FORECAST PERIOD. 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. REFER TO SUPER TYPHOON 26W (MANGKHUT) WARNINGS (WTPN31
PGTW) FOR SIX-HOURLY UPDATES.//
NNNN