Busy: 4 systems being tracked. Halong(24W) still a Super Typhoon



Météo974

M974World

WESTERN NORTH PACIFIC


STY 24W: INTENSITY FORECAST TO BE BELOW STY LEVEL AFTER 24H
STY 24W: INTENSITY FORECAST TO BE BELOW STY LEVEL AFTER 24H
WDPN31 PGTW 060300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR SUPER TYPHOON 24W (HALONG) WARNING NR
015//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
   SUPER TYPHOON (STY) 24W (HALONG), LOCATED APPROXIMATELY 565 NM EAST-
SOUTHEAST OF IWO TO, HAS TRACKED NORTHWARD AT 05 KNOTS (KTS) OVER THE
PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS
BANDING WRAPPING INTO A 10 NM SYMMETRIC EYE, PLACING HIGH CONFIDENCE IN
THE INITIAL POSITION. THE CURRENT INTENSITY OF 150 KTS IS BASED ON A
051803Z SATCON ESTIMATE OF 151 KTS AND MULTI-AGENCY DVORAK CURRENT
INTENSITY ESTIMATES OF T7.5 (155 KTS) FROM PGTW AND RJTD. STY 24W IS
LOCATED IN A REGION OF GOOD POLEWARD OUTFLOW AND LOW (05-10 KTS)
VERTICAL WIND SHEAR (VWS). SEA SURFACE TEMPERATURES ARE WARM AT 28-29
CELSIUS. THE SYSTEM IS TRACKING NORTHWARD ALONG THE WESTERN PERIPHERY OF
A DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE EAST.
3. FORECAST REASONING.
   A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM THE
PREVIOUS PROGNOSTIC REASONING MESSAGE. WIND RADII HAVE BEEN UPDATED
BASED ON A 052316Z METOP-B ASCAT PASS.
   B. STY 24W IS EXPECTED TO CREST THE STR AXIS BY TAU 12, RECURVING TO
A NORTH-NORTHEASTWARD TRACK. THE SYSTEM WILL MAINTAIN THIS TRACK UNTIL
TAU 48. AT THAT POINT, INTERACTION WITH A MIDLATITUDE TROUGH TO THE
NORTH WILL CAUSE THE SYSTEM TO ACCELERATE NORTHEASTWARD AND BEGIN
EXTRATROPICAL TRANSITION (ETT). DUE TO INCREASING VWS AND SLOW TRACK
MOTION OVER WATERS WITH LOW OCEAN HEAT CONTENT, STY 24W IS EXPECTED TO
GRADUALLY WEAKEN THROUGHOUT THIS FORECAST PERIOD. BY TAU 72, THE SYSTEM
IS EXPECTED TO COMPLETE ETT AND TAKE ON FRONTAL CHARACTERISTICS.
NUMERICAL MODELS ARE IN GOOD AGREEMENT THROUGHOUT THE FORECAST PERIOD.
THERE ARE SLIGHT VARIATIONS REGARDING THE COMPLETION OF THE RECURVE,
CREATING SOME ALONG TRACK DIFFERENCES. THE JTWC FORECAST TRACK IS PLACED
NEAR THE MULTI-MODEL CONSENSUS, SUPPORTING OVERALL GOOD CONFIDENCE IN
THE JTWC TRACK FORECAST.//
NNNN

TD 25W: FORECAST TO PEAK NEAR 60KTS IN 36/48H
TD 25W: FORECAST TO PEAK NEAR 60KTS IN 36/48H
WDPN32 PGTW 060300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 25W (NAKRI) WARNING
NR 02//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 25W (NAKRI), LOCATED APPROXIMATELY 477 NM EAST-
SOUTHEAST OF DA NANG, VIETNAM, HAS TRACKED SOUTH-SOUTHEASTWARD AT 03
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) DEPICTS CYCLING CONVECTION STILL DISPLACED WEST AND EAST
OF A CONSOLIDATING LOW LEVEL CIRCULATION CENTER. THE INITIAL INTENSITY
IS SET AT 30 KTS BASED ON DVORAK CURRENT INTENSITY ESTIMATES RANGING
FROM T1.5 (25 KTS) TO T2.5 (35 KTS) FROM KNES, PGTW, AND RJTD
RESPECTIVELY. EXCELLENT POLEWARD OUTFLOW TAPPING INTO THE MIDLATITUDE
JET TO THE NORTH AND LOW TO MODERATE (10-15 KT) VERTICAL WIND SHEAR
ARE ENABLING SLOW CONSOLIDATION AND DEVELOPMENT. TD 25W HAS BEEN
SLOWLY MEANDERING SOUTHEASTWARD IN THE SOUTH CHINA SEA IN A WEAK
STEERING ENVIRONMENT.
3. FORECAST REASONING.
   A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM
THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
   B. TD 25W IS FORECAST TO DRIFT SLOWLY EASTWARD IN THE NEXT 36 HOURS
IN AN AMBIGUOUS STEERING ENVIRONMENT. IT WILL GRADUALLY INTENSIFY TO A
PEAK OF 60 KTS AT TAU 36 DUE TO THE ROBUST POLEWARD OUTFLOW AND WARM
(29 DEGREES CELSIUS) SEA SURFACE TEMPERATURES, WHICH WILL BE OFFSET BY
MODERATE VWS, WHICH WILL LIMIT TOTAL INTENSIFICATION POTENTIAL. THERE
IS HIGH UNCERTAINTY IN THIS PORTION OF THE FORECAST TRACK. THE UKMET
ENSEMBLE TURNS 25W TO THE NORTH IN THE NEAR TERM, WHILE GFS, THE GFS
ENSEMBLE, AND THE ECMWF ENSEMBLE TURN 25W SLOWLY TO THE SOUTH IN THE
NEAR TERM, WITH THE ECMWF ENSEMBLE THE SOUTHERNMOST OUTLIER. HOWEVER,
THE SYSTEM WILL BE MOVING SLOWLY, OR EVEN BECOME QUASISTATIONARY
DURING THIS PERIOD, SO DESPITE DIFFERENCES IN THE MODELS, FORECAST
TRACK ERROR SHOULD BE LOW. ALL MODELS THEN REFLECT A WESTWARD TURN AND
ACCELERATION AFTER TAU 36 AS A SUBTROPICAL RIDGE BUILDS IN TO THE WEST
AND BECOMES THE DOMINANT STEERING FEATURE. THE GFS SOLUTION IS
SIGNIFICANTLY SLOWER THAN THE MULTIMODEL CONSENSUS IN ALONG-TRACK
SPEED AFTER TAU 36. THE JTWC FORECAST TRACK FAVORS THE SOUTHERN
SOLUTION AND IS PLACED JUST SOUTH OF THE MULTIMODEL CONSENSUS, TOWARDS
THE ECMWF AND GFS SOLUTIONS, WITH LOW CONFIDENCE.
C. AFTER TAU 72, ALL MODELS AGREE ON A WESTWARD TRACK TOWARDS VIETNAM.
TD 25W IS FORECAST TO MAKE LANDFALL AFTER TAU 96. IT WILL BEGIN A
GRADUAL WEAKENING TREND AFTER TAU 72 AS UPPER LEVEL DIVERGENCE
DECREASES, AND THEN WEAKEN MORE RAPIDLY DUE TO LAND INTERACTION AFTER
TAU 96. THERE IS HIGH CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST
TRACK.//
NNNN

TC 05A: NOW BELOW TYPHOON INTENSITY AND WEAKENING
TC 05A: NOW BELOW TYPHOON INTENSITY AND WEAKENING
REMARKS:
060300Z POSITION NEAR 19.8N 66.7E.
06NOV19. TROPICAL CYCLONE (TC) 05A (MAHA), LOCATED APPROXIMATELY 303
NM SOUTH OF KARACHI, PAKISTAN, HAS TRACKED EASTWARD AT 13 KNOTS (KTS)
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR) SATELLITE
IMAGERY REVEALS A DEGRADED CONVECTIVE STRUCTURE WHICH HAS BEGUN TO
SHEAR. WATER VAPOR IMAGERY SHOWS DRY AIR WRAPPING INTO THE CENTER OF
TC 05A. THE INITIAL POSITION IS SET WITH GOOD CONFIDENCE, SUPPORTED BY
A 052327Z SSMI 85 GHZ COLORPCT MICROWAVE IMAGE.  THE INITIAL INTENSITY
IS SET AT 60 KTS WITH GOOD CONFIDENCE, PLACED BETWEEN A 052124Z SATCON
ESTIMATE OF 49 KTS AND MULTI-AGENCY DVORAK CURRENT INTENSITY ESTIMATES
OF T4.0 (65 KTS) FROM PGTW AND DEMS, BASED ON THE WEAKENING STRUCTURE
AND DEEP CONVECTION. ANALYSIS OF THE ENVIRONMENT INDICATES HIGH (25-30
KTS) VERTICAL WIND SHEAR, GOOD POLEWARD OUTFLOW, AND WARM (27 CELSIUS)
SEA SURFACE TEMPERATURES (SST). TC 05A IS BEING PULLED EASTWARD BY THE
UPPER LEVEL WESTERLY FLOW WHICH HAS EXTENDED SOUTH INTO THE ARABIAN
SEA VIA TROUGHING. THIS WESTERLY FLOW BRIEFLY ENHANCED THE OUTFLOW;
HOWEVER, THE CONVERGENT WESTERLIES ALOFT AND INCREASING VWS WILL
QUICKLY ERODE THE SYSTEM THROUGH THE REMAINDER OF THE FORECAST PERIOD.
DISSIPATION IS ANTICIPATED BY TAU 36. THE JTWC TRACK FORECAST IS
PLACED NEAR MODEL CONSENSUS WITH NAVGEM AS AN OUTLIER TO THE NORTH
THROUGH TAU 36. NAVGEM, UKMET ENSEMBLE, AND GEFS SUPPORT AN ALTERNATE
MODEL SOLUTION WHERE THE TRACK IS EXTENDED AND TC 05A TURNS
SOUTHWESTWARD AFTER TAU 48, RETURNING TO THE ARABIAN SEA. THE OFFICIAL
JTWC FORECAST TRACK STILL FAVORS THE EASTWARD SOLUTION WITH
DISSIPATION AT TAU 36 AS IT IS MORE DYNAMICALLY SUPPORTED. MAXIMUM
SIGNIFICANT WAVE HEIGHT AT 060000Z IS 33 FEET. NEXT WARNINGS AT
060900Z, 061500Z, 062100Z AND 070300Z.//
NNNN

23W: TROPICAL CYCLONE FORMATION ALERT OVER THE BAY OF BENGAL
23W: TROPICAL CYCLONE FORMATION ALERT OVER THE BAY OF BENGAL
WTIO21 PGTW 060400
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (REMNANTS 23W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 15.2N 88.5E TO 12.4N 89.5E 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 25 TO 30 KNOTS. METSAT IMAGERY AT 060000Z
INDICATES THAT A CIRCULATION CENTER IS LOCATED NEAR 13.0N 89.3E. THE
SYSTEM IS MOVING WESTWARD AT 04 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (REMNANTS 23W) PREVIOUSLY LOCATED
NEAR 13.4N 90.0E IS NOW LOCATED NEAR 13.0N 89.3E, APPROXIMATELY 575
NM SOUTH-SOUTHWEST OF CHITTAGONG, BANGLADESH. ANIMATED MULTISPECTRAL
SATELLITE IMAGERY (MSI) SHOWS LOW LEVEL TURNING UNDERNEATH A CIRRUS
SHIELD. A 051548Z METOP-B ASCAT IMAGE DEPICTS A CIRCULATION WITH AN
AREA OF 30-35 KNOT WINDS IN THE WESTERN SEMI-CIRCLE. UPPER LEVEL
ANALYSIS REVEALS GOOD POLEWARD OUTFLOW AND MODERATE (20 KT) VERTICAL
WIND SHEAR. THE SEA SURFACE TEMPERATURE IS FAVORABLE AT 27-28
DEGREES CELSIUS. NUMERICAL MODELS ARE IN GOOD AGREEMENT, SHOWING
DEVELOPMENT AND INTENSIFICATION WITHIN THE NEXT 24 HOURS AS THE
SYSTEM TRACKS SLOWLY NORTH-NORTHWESTWARD. THE ECMWF ENSEMBLE IS THE
CURRENT MODEL OUTLIER AS IT MAINTAINS A MORE WESTERN TRACK. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 25 TO 30 KNOTS. MINIMUM SEA
LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1003 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
070400Z.//
NNNN

STY 24W: TRACK AND INTENSITY GUIDANCE
STY 24W: TRACK AND INTENSITY GUIDANCE

TD 25W: TRACK AND INTENSITY GUIDANCE
TD 25W: TRACK AND INTENSITY GUIDANCE

TC 05A: TRACK AND INTENSITY GUIDANCE
TC 05A: TRACK AND INTENSITY GUIDANCE

ex 23W: TRACK AND INTENSITY GUIDANCE
ex 23W: TRACK AND INTENSITY GUIDANCE
Rédigé par PATRICK HOAREAU le Mercredi 6 Novembre 2019 à 09:08