WPAC: 08W - Post-Tropical

[Hayabusa]

97W INVEST 210703 1200 13.0N 122.0E WPAC 15 0

[Hayabusa]

WWJP27 RJTD 031800
WARNING AND SUMMARY 031800.
WARNING VALID 041800.
WARNING IS UPDATED EVERY 6 HOURS.
LOW PRESSURE AREA 1004 HPA NEAR 14N 122E WNW SLOWLY.

ABPW10 PGTW 040100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS REISSUED/040100Z-040600ZJUL2021//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/031921ZJUL2021//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
(2) AN AREA OF CONVECTION (INVEST 97W) HAS PERSISTED NEAR
13.1N 121.1E, APPROXIMATELY 93 NM SOUTH OF MANILLA. ANIMATED
MULTISPECTRAL IMAGERY (MSI) AND A 032050Z SSMIS 91GHZ MICROWAVE
IMAGE DEPICT FLARING CONVECTION IN THE WESTERN PERIPHERY OF A WEAK
LOW LEVEL CIRCULATION CENTERED OVER THE EASTERN PORTION OF MINDORO
ISLAND. ENVIRONMENTAL ANALYSIS SHOWS FAVORABLE CONDITIONS FOR
DEVELOPMENT, WITH GOOD EQUATORWARD OUTFLOW, LOW (10-15KTS) VERTICAL
WIND SHEAR (VWS), AND VERY WARM (30-31C) SEA SURFACE TEMPERATURES
(SST). NUMERICAL MODELS ARE IN GENERAL AGREEMENT THAT 97W WILL TRACK
NORTHWESTWARD BUT ARE SPLIT REGARDING INTENSIFICATION, WITH ECMWF
DETERMINISTIC MODEL, THE ECMWF ENSEMBLE, AND NAVGEM SHOWING
DEVELOPMENT IN THE NEXT TWO TO THREE DAYS WHILE THE GFS AND JGSM ARE
BELOW WARNING CRITERIA. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1010 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

[Hayabusa]

[Hayabusa]

ABPW10 PGTW 040600
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
SOUTH PACIFIC OCEANS/040600Z-050600ZJUL2021//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/031921ZJUL2021//
AMPN/REF A IS A TROPICAL CYCLONE FORMATION ALERT.//
RMKS/
(2) THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED
NEAR 13.1N 121.1E IS NOW LOCATED NEAR 13.7N 118.8E, APPROXIMATELY
137 NM WEST-SOUTHWEST OF MANILA, PHILIPPINES. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY (MSI) AND A 040202Z METOP-B IMAGE DEPICT 15 TO 20
KNOT WINDS AND FLARING CONVECTION IN THE WESTERN PERIPHERY OF AN
ELONGATED LOW LEVEL CIRCULATION (LLC). ENVIRONMENTAL ANALYSIS SHOWS
FAVORABLE CONDITIONS FOR DEVELOPMENT, WITH GOOD EQUATORWARD OUTFLOW,
LOW (10-15KTS) VERTICAL WIND SHEAR (VWS), AND VERY WARM (30-31C) SEA
SURFACE TEMPERATURES (SST). NUMERICAL MODELS ARE IN GENERAL
AGREEMENT THAT 97W WILL TRACK NORTHWESTWARD BUT ARE SPLIT REGARDING
INTENSIFICATION, WITH ECMWF DETERMINISTIC MODEL, THE ECMWF ENSEMBLE,
AND NAVGEM SHOWING DEVELOPMENT IN THE NEXT TWO TO THREE DAYS WHILE
THE GFS AND JGSM ARE BELOW WARNING CRITERIA. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 12 TO 18 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1008 MB. THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS IS UPGRADED TO MEDIUM.

[underthwx]

Hi everyone!..... I have a very close friend that lives in Metro Manila... Does 97W pose any potential impacts in that area?... Thankyou for any info

[doomhaMwx]

The CMA is now warning on this as a TD and expects it to become a TS while moving towards Hainan Island over the next couple of days.

[Subtrop]

WWJP27 RJTD 051800
WARNING AND SUMMARY 051800.
WARNING VALID 061800.
WARNING IS UPDATED EVERY 6 HOURS.

TROPICAL DEPRESSION 1002 HPA AT 16N 112E WNW SLOWLY.

JAPAN METEOROLOGICAL AGENCY.=

WTPN21 PGTW 060030
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 97W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
095 NM EITHER SIDE OF A LINE FROM 15.6N 112.6E TO 17.9N 110.5E
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 18 TO 23 KNOTS. METSAT
IMAGERY AT 051800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 15.6N 112.5E. THE SYSTEM IS MOVING WEST-NORTHWESTWARD AT 05
KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 97W) PREVIOUSLY LOCATED
NEAR 15.4N 113.0E IS NOW LOCATED NEAR 15.6N 112.5E, APPROXIMATELY
298NM SOUTH-SOUTHEAST OF HAINAN. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY AND A 052108Z SSMI 85GHZ MICROWAVE IMAGE DEPICTS A BROAD LOW
LEVEL CIRCULATION (LLC) WITH FLARING CONVECTION SHEARED ALONG THE
WESTERN SEMICIRCLE OF THE LLC. UPPER-LEVEL ANALYSIS REVEALS A
FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW TO MODERATE VERTICAL
WIND SHEAR (VWS), GOOD POLEWARD OUTFLOW, AND WARM SEA SURFACE
TEMPERATURES (30-31C). GLOBAL DYNAMIC MODELS ARE IN GOOD AGREEMENT
THAT 97W WILL CONTINUE TO TRACK ALONG THE PERIPHERY OF A SUBTROPICAL
RIDGE SITUATED TO THE NORTHEAST AS IT CONSOLIDATES AND TRACKS
TOWARDS HAINAN. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18
TO 23 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1005
MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL
CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
070030Z.//
NNNN

[doomhaMwx]

WDPN31 PGTW 071500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 08W (EIGHT)
WARNING NR 001//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 19.2N 108.0E
INITIAL INTENSITY: 25 KTS
GEOGRAPHIC REFERENCE: 160 NM SOUTHEAST OF HANOI, VIETNAM
MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 15 KTS
SIGNIFICANT WAVE HEIGHT: 10 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A RAGGED DEEP CONVECTIVE STRUCTURE BEGINNING TO LOCALIZE AROUND A LOW-LEVEL CIRCULATION CENTER (LLCC) WITH DEEP CONVECTIVE BURSTS OVER MAINLY THE WESTERN AND SOUTHERN SEMICIRCLES. A PARTIAL 071144Z SSMIS 91GHZ MICROWAVE IMAGE INDICATES FRAGMENTED, FORMATIVE BANDING PRIMARILY OVER THE WESTERN SEMICIRCLE. THE INITIAL POSITION IS PLACED WITH LOW CONFIDENCE BASED ON THE EIR LOOP AND THE PARTIAL MICROWAVE IMAGE. THE INITIAL INTENSITY OF 25 KTS IS ASSESSED WITH LOW
CONFIDENCE BASED ON MULTIPLE AGENCY DVORAK ESTIMATES OF T1.0, CONSISTENT WITH THE OVERALL STRUCTURE. THE ENVIRONMENTAL ANALYSIS
IS MARGINALLY FAVORABLE DUE TO THE STRONG UPPER-LEVEL EASTERLY OUTFLOW, WHICH IS PREDOMINATELY OFFSET BY THE MODERATE TO HIGH
VERTICAL WIND SHEAR.

INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND RADII).

CURRENT STEERING MECHANISM: DEEP-LAYERED SUBTROPICAL RIDGE (STR) POSITIONED TO THE NORTHEAST.

AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T1.0 - 25 KTS
RJTD: T1.0 - 25 KTS

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY FAVORABLE
VWS: 20-25 KTS
SST: 29-30 CELSIUS
OUTFLOW: MODERATE WESTWARD

ANALYSIS CONFIDENCE:
INITIAL POSITION: LOW
INITIAL INTENSITY: LOW
INITIAL WIND RADII: NOT APPLICABLE

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING

MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY.

FORECAST DISCUSSION: TD 08W IS FORECAST TO TRACK AROUND THE SOUTHWEST PERIPHERY OF THE DEEP-LAYERED STR TOWARD VIETNAM THROUGH THE REMAINDER OF THE FORECAST PERIOD. THE SYSTEM AT CURRENT IS DISORGANIZED BUT WILL CONSOLIDATE AROUND THE LLCC AS THE STRONG VWS WILL BEGIN TO DECREASE TO 10-15KTS WITHIN THE NEXT 12 HOURS. ONCE THE VWS DECREASES THE STRONG OUTFLOW WILL HELP THE INTENSITY REACH A PEAK OF 30 KTS BEFORE MAKING LANDFALL SOUTH OF HANOI, VIETNAM, JUST AFTER TAU 12. THEREAFTER, THE SYSTEM WILL MAKE LANDFALL AND BEGIN DISSIPATION OVER THE RUGGED TERRAIN OVER VIETNAM AND LAOS.

MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN TIGHT AGREEMENT ON THE FORECAST TO MAKE LANDFALL JUST SOUTH OF HANOI, VIETNAM,
WITH A VERY SMALL CROSS-TRACK SPREAD OF ONLY 46NM THROUGH TAU 24. THE JTWC FORECAST TRACK IS POSITIONED CLOSE TO THE MULTI-MODEL
CONSENSUS, BUT SLIGHTLY EQUATORWARD TOWARD THE BULK OF THE MODEL SOLUTIONS, WHICH ARE ON THE SOUTHERN EDGE OF THE AIDS ENVELOPE. AFUM AND EEMN REMAIN THE TWO MOST SIGNIFICANT POLEWARD OUTLIERS FROM CONSENSUS.

FORECAST CONFIDENCE:
TRACK 0 - 72 HR: MEDIUM
INTENSITY 0 - 72 HR: MEDIUM//
NNNN

[ElectricStorm]

Looks like this briefly became a TD before landfall
08W EIGHT 210707 1200 19.6N 107.6E WPAC 25 1001

[doomhaMwx]

REMARKS:
072100Z POSITION NEAR 20.5N 106.1E.
07JUL21. TROPICAL DEPRESSION 08W (EIGHT), LOCATED APPROXIMATELY
46 NM SOUTHEAST OF HANOI, VIETNAM, HAS TRACKED NORTHWESTWARD AT
14 KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED
SATELLITE IMAGERY DEPICTS SHEARED CONVECTION TO THE WEST OF A POORLY
ORGANIZED LOW LEVEL CIRCULATION THAT IS NOW CROSSING OVER THE COAST
OF VIETNAM. THE INITIAL POSITION IS PLACED SLIGHTLY WEST OF THE PGTW
POSITION FIX AND THE INITIAL INTENSITY OF 20 KTS IS HEDGED SLIGHTLY
LOWER THAN THE PGTW CURRENT INTENSITY ESTIMATE OF 1.0 (25 KTS).
RECENT MICROWAVE IMAGERY SHOWS NO INDICATION OF ANY SIGNIFICANT
CONVECTIVE STRUCTURE REMAINING. DUE TO LAND INTERACTION AND HIGH
VERTICAL WIND SHEAR (>25 KTS), TD 08W HAS DISSIPATED AND IS FORECAST
DECREASE TO 15 KTS WITHIN 24 HOURS. 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.//
NNNN