CLICK ON THE IMAGERIES BELOW TO GET THEM ENLARGED
JTWC IS ISSUING 6 HOURLY WARNINGS AND 3 HOURLY SATELLITE BULLETINS ON 12W. 3 HOURLY SATELLITE BULLETINS ARE ISSUED ON 94W
WESTERN PACIFIC: TY 12W(DOLPHIN). WARNING 34 ISSUED BY JTWC @ 04/0900 UTC
PROGNOSTIC REASONING
WDPN31 PGTW 040900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W (DOLPHIN) WARNING NR 034//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 25.3N 141.9E
INITIAL INTENSITY: 115 KTS
GEOGRAPHIC REFERENCE: 44 NM NORTHEAST OF IWO TO
MOVEMENT PAST 6 HOURS: WESTWARD AT 11 KTS
SIGNIFICANT WAVE HEIGHT: 52 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
TYPHOON (TY) 12W (DOLPHIN) HAS UNDERGONE A REMARKABLE TRANSFORMATION
OVER THE PAST 6-12 HOURS, WITH THE INNER CORE EXPERIENCING A
REINCARNATION OF SORTS. A SERIES OF MICROWAVE IMAGES BETWEEN 032200Z
AND 040413Z, INCLUDING A GMI AND AMSR2 PASS, REVEALED THAT THE OUTER
RING OF CONVECTION LOCATED APPROXIMATELY 100NM DISTANT FROM THE CENTER
HAS BEGUN TO FRAGMENT AND WEAKEN, PARTICULARLY ON THE WESTERN SIDE.
THE OVERALL WEAKENING OF THE OUTER RING OF CONVECTION HAS ALLOWED THE
INNER CORE TO STEADILY CONSOLIDATE, WITH THE 040413Z AMSR2 89H
MICROWAVE IMAGE DEPICTING A FULLY ENCLOSED INNER EYEWALL. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A 15NM WIDE, CLOUD-FREE
EYE PASSING DIRECTLY OVER THE ISLAND OF NORTH IWO TO. EYE TEMPERATURES
HAVE INCREASED RAPIDLY OVER THE PAST TWO HOURS AND ARE CURRENTLY
ESTIMATED AT 14C. CLOUD TOP TEMPERATURES HAVE ALSO COOLED
SIGNIFICANTLY OVER THE PAST 12 HOURS BUT ARE NOW BEGINNING TO LEVEL
OFF AND EVEN WARM SLIGHTLY. ANIMATED WATER VAPOR IMAGERY DEPICTS
VIGOROUS RADIAL OUTFLOW AS WELL AS A STRONG POLEWARD OUTFLOW CHANNEL
INTO THE BASE OF AN UPPER-LEVEL TROUGH WHICH EXTENDS FROM NORTH OF TY
12W FAR OFF TO THE NORTHEAST. THE SYSTEM HAS EXHIBITED SOME TROCHOIDAL
MOTION OVER THE PAST SIX HOURS, BUT IN THE LAST THREE HOURS HAS
STABILIZED ONTO A DUE WESTWARD TRACK. THE INITIAL POSITION IS ASSESSED
WITH HIGH CONFIDENCE BASED ON THE EYE FEATURE IN THE MSI AND
EXTRAPOLATION OF THE MICROWAVE EYE IN THE AMSR2 IMAGE NOTED ABOVE. THE
INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE, BIASED TOWARDS
THE T6.0 DVORAK CURRENT INTENSITY ESTIMATES FROM PGTW, RJTD AND RCTP
AS WELL AS THE 117 KNOT ESTIMATE FROM CIMSS ADT. ENVIRONMENTAL
CONDITIONS ARE FAVORABLE. THE SYSTEM IS MOVING OVER THE WARMEST WATERS
IN THE WESTERN PACIFIC, THOUGH THE DEPTH OF THE WARM LAYER IS
RELATIVELY SHALLOW, GENERATING LOW OHC. UPPER-LEVEL OUTFLOW REMAINS
STRONG AND DEEP-LAYER SHEAR IS LOW, THOUGH MODEL-BASED SOUNDINGS
SUGGEST A SLIGHTLY HIGHER AMOUNT OF NORTHWESTERLY SHEAR IN THE
UPPERLEVELS OF THE ATMOSPHERE, WHICH SEEMS TO BE EVIDENT IN THE
OVERALL SATELLITE APPEARANCE.
INITIAL WIND RADII BASIS: SCATTEROMETER DATA
CURRENT STEERING MECHANISM: SOUTHEASTERN FLANK OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED IN THE SEA OF JAPAN.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T6.0 - 115 KTS
RJTD: T6.0 - 115 KTS
RCTP: T6.0 - 115 KTS
KNES: T5.5 - 102 KTS
CIMSS SATCON: 100 KTS AT 040530Z
CIMSS ADT: 117 KTS AT 040600Z
CIMSS AIDT: 109 KTS AT 040600Z
CIMSS D-MINT: 104 KTS AT 040413Z
CIMSS D-PRINT: 90 KTS AT 040640Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG RADIAL
OTHER FACTORS: SLIGHTLY ELEVATED NORTHWESTERLY SHEAR IN THE
400-150MB LEVEL; UPWELLING OF COOLER SUBSURFACE WATERS.
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: HIGH
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TY 12W IS FORECAST TO CONTINUE TRACKING
WESTWARD AT A NEARLY CONSTANT SPEED, ALONG THE SOUTHERN FLANK OF A
DEEP-LAYER STR, CENTERED ANOMALOUSLY IN THE SEA OF JAPAN. THE
SYSTEM WILL BEGIN TO SLOW DOWN AFTER TAU 60, AS A STRONG
UPPER-LEVEL TROUGH MOVES INTO NORTHEASTERN MANCHURIA AND BEGINS TO
ERODE THE STR FROM THE WEST. BY TAU 72 TO TAU 84, THE TROUGH WILL
HAVE ERODED THE STR ENOUGH FOR A WEAKNESS TO DEVELOP OVER THE
KOREAN PENINSULA, AND THIS WEAKNESS WILL HAVE A SIGNIFICANT IMPACT
ON THE LONG-RANGE FORECAST FOR TY 12W. ALL FOUR PRIMARY GLOBAL
MODELS DEPICT THE WEAKNESS WITH THE SAME ORIENTATION, STRENGTH AND
TIMING. HOWEVER, THE MODELS ARE BEGINNING TO SHOW MAJOR DIFFERENCES
IN THE OVERALL IMPACT ON TY 12W. THE GFS HAS SHIFTED AGGRESSIVELY
SINCE THE PREVIOUS RUN, NOW SHOWING THE SYSTEM STALLING PRIOR TO
REACHING OKINAWA THEN TURNING NORTH BY TAU 120, JOINING THE NAVGEM
AND JGSM MODELS IN THIS DEPICTION. THE ECMWF AND THE MAJORITY OF THE
ENSEMBLES SUPPORT A STEADY WESTWARD, ALBEIT WITH SIGNIFICANT
SLOWING, THROUGH THE END OF THE FORECAST PERIOD. THE NAVGEM AND
JGSM HAVE KNOWN POLEWARD BIASES IN THESE SCENARIOS, WHERE AS THE GFS
EXHIBITS LESS OF A BIAS. HOWEVER, THE PREPONDERANCE OF THE MODELS
(DETERMINISTIC, ENSEMBLE AND AI) SUPPORT PERSISTENCE OF THE WESTWARD
TRACK THROUGH TAU 120, AS THE WEAKNESS IN THE RIDGE DOES NOT APPEAR AT
THIS TIME TO BE STRONG ENOUGH TO INFLUENCE TY 12W TO TRACK NORTHWARD
AS PRONOUNCED AS. THE FORECAST CALLS FOR LANDFALL ON OKINAWA SHORTLY
AFTER TAU 72. THOUGH SOMEWHAT DELAYED, THE SYSTEM HAS COMPLETED THE
FOURTH EYEWALL REPLACEMENT CYCLE (ERC) AND HAS REINTENSIFIED WITH A
RENEWED VIGOR. THE SYSTEM IS EXPECTED TO BRIEFLY REACH 120 KNOTS
WITHIN THE NEXT FEW HOURS, BUT THIS FIFTH PEAK INTENSITY WILL BE
SHORT-LIVED. ALREADY, THE EYE IS SHOWING SIGNS OF ENLARGING AND THE
MSI AND INFRARED IMAGERY SUGGEST A LARGER EYEWALL IS BEGINNING TO
FORM. ADDITIONALLY, DUE TO THE EXTREMELY LARGE SIZE OF THE SYSTEM,
OCEANIC UPWELLING IS OCCURRING ACROSS A WIDE REGION, RESULTING IN A
GENERAL COOLING OF SSTS ALONG THE TRACK. ALL MESOSCALE MODELS SUPPORT
A SLOWLY BUT STEADILY ENLARGING INNER CORE AS THE SYSTEM PROGRESSES
WESTWARD, SUPPORTING A SLOW STEP-WISE WEAKENING, AS DEPICTED IN THE
JTWC FORECAST. HOWEVER, THE SYSTEM IS EXPECTED TO REMAIN A SIGNIFICANT
TYPHOON AS IT CROSSES THE RYUKYU ISLANDS AND IMPACTS OKINAWA.
MODEL DISCUSSION: UP TO TAU 60, THE TRACK CONSENSUS, AS WELL AS THE
ENSEMBLE MEANS, ARE TIGHTLY CONSTRAINED TO A VERY NARROW ENVELOPE,
WITH MINIMAL CROSS- OR ALONG-TRACK UNCERTAINTY. THE JTWC FORECAST IS
PLACED NEAR THE MULTI-MODEL CONSENSUS MEAN AS WELL AS THE AI CONSENSUS
MEAN WITH HIGH CONFIDENCE. AFTER TAU 60, THE GUIDANCE BEGINS TO
DIVERGE RAPIDLY. AS DISCUSSED ABOVE, THE GFS, NAVGEM AND JGSM ALL
DEPART FROM THE TIGHTLY CONSTRAINED MODEL ENVELOPE, INITIALLY MOVING
SOUTHWESTWARD, SLOWING DOWN TO NEARLY QUASI-STATIONARY SPEEDS, AND
THEN RAPIDLY TURN NORTHWARD AFTER TAU 72, ENDING UP BETWEEN AMAMI
OSHIMA AND YAKUSHIMA BY TAU 120. THE REMAINDER OF THE DETERMINISTIC
MODELS (ECMWF, GALWEM, UKMET), THE GEFS, AND ECENS ENSEMBLE MEANS, AS
WELL AS ALL AVAILABLE AI MODEL TRACKERS, MOVE THE SYSTEM WESTWARD INTO
THE EAST CHINA SEA, WITH STEADILY DECREASING SPEED. THE JTWC FORECAST
IS PLACED NORTH OF THE ECMWF, BUT SOUTH OF THE GEFS AND ECENS MEANS,
CLOSE TO THE AI CONSENSUS MEAN. THE JTWC EXPERIMENTAL SUPER ENSEMBLE
SHOWS A TIGHT MEMBER ENVELOPE THROUGH TAU 72, WITH INCREASED MEMBER
DISPERSION THEREAFTER, WITH A FOCUS ON A NORTHWARD TURN AFTER TAU 96.
CONFIDENCE IN THE EXTENDED FORECAST IS MEDIUM IN LIGHT OF THE
INCREASED UNCERTAINTY IN THE ENSEMBLE MEMBERS AND RECENT SHIFT IN
SEVERAL OF THE MODEL TRACKERS. INTENSITY GUIDANCE IS FOR THE MOST PART
IN GOOD AGREEMENT. THE ONLY MODEL SHOWING INTENSIFICATION IS CTCX,
WHILE THE REMAINDER OF THE CONSENSUS DEPICTS A GRADUAL WEAKENING
THROUGH THE FORECAST PERIOD, SUPPORTING THE JTWC FORECAST WITH MEDIUM
CONFIDENCE.
FORECAST CONFIDENCE:
TRACK 00-72 HR: HIGH
TRACK 72-120 HR: MEDIUM
INTENSITY 00-72 HR: MEDIUM
INTENSITY 72-120 HR: LOW//
NNNN
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 12W (DOLPHIN) WARNING NR 034//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 25.3N 141.9E
INITIAL INTENSITY: 115 KTS
GEOGRAPHIC REFERENCE: 44 NM NORTHEAST OF IWO TO
MOVEMENT PAST 6 HOURS: WESTWARD AT 11 KTS
SIGNIFICANT WAVE HEIGHT: 52 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
TYPHOON (TY) 12W (DOLPHIN) HAS UNDERGONE A REMARKABLE TRANSFORMATION
OVER THE PAST 6-12 HOURS, WITH THE INNER CORE EXPERIENCING A
REINCARNATION OF SORTS. A SERIES OF MICROWAVE IMAGES BETWEEN 032200Z
AND 040413Z, INCLUDING A GMI AND AMSR2 PASS, REVEALED THAT THE OUTER
RING OF CONVECTION LOCATED APPROXIMATELY 100NM DISTANT FROM THE CENTER
HAS BEGUN TO FRAGMENT AND WEAKEN, PARTICULARLY ON THE WESTERN SIDE.
THE OVERALL WEAKENING OF THE OUTER RING OF CONVECTION HAS ALLOWED THE
INNER CORE TO STEADILY CONSOLIDATE, WITH THE 040413Z AMSR2 89H
MICROWAVE IMAGE DEPICTING A FULLY ENCLOSED INNER EYEWALL. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A 15NM WIDE, CLOUD-FREE
EYE PASSING DIRECTLY OVER THE ISLAND OF NORTH IWO TO. EYE TEMPERATURES
HAVE INCREASED RAPIDLY OVER THE PAST TWO HOURS AND ARE CURRENTLY
ESTIMATED AT 14C. CLOUD TOP TEMPERATURES HAVE ALSO COOLED
SIGNIFICANTLY OVER THE PAST 12 HOURS BUT ARE NOW BEGINNING TO LEVEL
OFF AND EVEN WARM SLIGHTLY. ANIMATED WATER VAPOR IMAGERY DEPICTS
VIGOROUS RADIAL OUTFLOW AS WELL AS A STRONG POLEWARD OUTFLOW CHANNEL
INTO THE BASE OF AN UPPER-LEVEL TROUGH WHICH EXTENDS FROM NORTH OF TY
12W FAR OFF TO THE NORTHEAST. THE SYSTEM HAS EXHIBITED SOME TROCHOIDAL
MOTION OVER THE PAST SIX HOURS, BUT IN THE LAST THREE HOURS HAS
STABILIZED ONTO A DUE WESTWARD TRACK. THE INITIAL POSITION IS ASSESSED
WITH HIGH CONFIDENCE BASED ON THE EYE FEATURE IN THE MSI AND
EXTRAPOLATION OF THE MICROWAVE EYE IN THE AMSR2 IMAGE NOTED ABOVE. THE
INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE, BIASED TOWARDS
THE T6.0 DVORAK CURRENT INTENSITY ESTIMATES FROM PGTW, RJTD AND RCTP
AS WELL AS THE 117 KNOT ESTIMATE FROM CIMSS ADT. ENVIRONMENTAL
CONDITIONS ARE FAVORABLE. THE SYSTEM IS MOVING OVER THE WARMEST WATERS
IN THE WESTERN PACIFIC, THOUGH THE DEPTH OF THE WARM LAYER IS
RELATIVELY SHALLOW, GENERATING LOW OHC. UPPER-LEVEL OUTFLOW REMAINS
STRONG AND DEEP-LAYER SHEAR IS LOW, THOUGH MODEL-BASED SOUNDINGS
SUGGEST A SLIGHTLY HIGHER AMOUNT OF NORTHWESTERLY SHEAR IN THE
UPPERLEVELS OF THE ATMOSPHERE, WHICH SEEMS TO BE EVIDENT IN THE
OVERALL SATELLITE APPEARANCE.
INITIAL WIND RADII BASIS: SCATTEROMETER DATA
CURRENT STEERING MECHANISM: SOUTHEASTERN FLANK OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED IN THE SEA OF JAPAN.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T6.0 - 115 KTS
RJTD: T6.0 - 115 KTS
RCTP: T6.0 - 115 KTS
KNES: T5.5 - 102 KTS
CIMSS SATCON: 100 KTS AT 040530Z
CIMSS ADT: 117 KTS AT 040600Z
CIMSS AIDT: 109 KTS AT 040600Z
CIMSS D-MINT: 104 KTS AT 040413Z
CIMSS D-PRINT: 90 KTS AT 040640Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 29-30 CELSIUS
OUTFLOW: STRONG RADIAL
OTHER FACTORS: SLIGHTLY ELEVATED NORTHWESTERLY SHEAR IN THE
400-150MB LEVEL; UPWELLING OF COOLER SUBSURFACE WATERS.
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: HIGH
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.
FORECAST DISCUSSION: TY 12W IS FORECAST TO CONTINUE TRACKING
WESTWARD AT A NEARLY CONSTANT SPEED, ALONG THE SOUTHERN FLANK OF A
DEEP-LAYER STR, CENTERED ANOMALOUSLY IN THE SEA OF JAPAN. THE
SYSTEM WILL BEGIN TO SLOW DOWN AFTER TAU 60, AS A STRONG
UPPER-LEVEL TROUGH MOVES INTO NORTHEASTERN MANCHURIA AND BEGINS TO
ERODE THE STR FROM THE WEST. BY TAU 72 TO TAU 84, THE TROUGH WILL
HAVE ERODED THE STR ENOUGH FOR A WEAKNESS TO DEVELOP OVER THE
KOREAN PENINSULA, AND THIS WEAKNESS WILL HAVE A SIGNIFICANT IMPACT
ON THE LONG-RANGE FORECAST FOR TY 12W. ALL FOUR PRIMARY GLOBAL
MODELS DEPICT THE WEAKNESS WITH THE SAME ORIENTATION, STRENGTH AND
TIMING. HOWEVER, THE MODELS ARE BEGINNING TO SHOW MAJOR DIFFERENCES
IN THE OVERALL IMPACT ON TY 12W. THE GFS HAS SHIFTED AGGRESSIVELY
SINCE THE PREVIOUS RUN, NOW SHOWING THE SYSTEM STALLING PRIOR TO
REACHING OKINAWA THEN TURNING NORTH BY TAU 120, JOINING THE NAVGEM
AND JGSM MODELS IN THIS DEPICTION. THE ECMWF AND THE MAJORITY OF THE
ENSEMBLES SUPPORT A STEADY WESTWARD, ALBEIT WITH SIGNIFICANT
SLOWING, THROUGH THE END OF THE FORECAST PERIOD. THE NAVGEM AND
JGSM HAVE KNOWN POLEWARD BIASES IN THESE SCENARIOS, WHERE AS THE GFS
EXHIBITS LESS OF A BIAS. HOWEVER, THE PREPONDERANCE OF THE MODELS
(DETERMINISTIC, ENSEMBLE AND AI) SUPPORT PERSISTENCE OF THE WESTWARD
TRACK THROUGH TAU 120, AS THE WEAKNESS IN THE RIDGE DOES NOT APPEAR AT
THIS TIME TO BE STRONG ENOUGH TO INFLUENCE TY 12W TO TRACK NORTHWARD
AS PRONOUNCED AS. THE FORECAST CALLS FOR LANDFALL ON OKINAWA SHORTLY
AFTER TAU 72. THOUGH SOMEWHAT DELAYED, THE SYSTEM HAS COMPLETED THE
FOURTH EYEWALL REPLACEMENT CYCLE (ERC) AND HAS REINTENSIFIED WITH A
RENEWED VIGOR. THE SYSTEM IS EXPECTED TO BRIEFLY REACH 120 KNOTS
WITHIN THE NEXT FEW HOURS, BUT THIS FIFTH PEAK INTENSITY WILL BE
SHORT-LIVED. ALREADY, THE EYE IS SHOWING SIGNS OF ENLARGING AND THE
MSI AND INFRARED IMAGERY SUGGEST A LARGER EYEWALL IS BEGINNING TO
FORM. ADDITIONALLY, DUE TO THE EXTREMELY LARGE SIZE OF THE SYSTEM,
OCEANIC UPWELLING IS OCCURRING ACROSS A WIDE REGION, RESULTING IN A
GENERAL COOLING OF SSTS ALONG THE TRACK. ALL MESOSCALE MODELS SUPPORT
A SLOWLY BUT STEADILY ENLARGING INNER CORE AS THE SYSTEM PROGRESSES
WESTWARD, SUPPORTING A SLOW STEP-WISE WEAKENING, AS DEPICTED IN THE
JTWC FORECAST. HOWEVER, THE SYSTEM IS EXPECTED TO REMAIN A SIGNIFICANT
TYPHOON AS IT CROSSES THE RYUKYU ISLANDS AND IMPACTS OKINAWA.
MODEL DISCUSSION: UP TO TAU 60, THE TRACK CONSENSUS, AS WELL AS THE
ENSEMBLE MEANS, ARE TIGHTLY CONSTRAINED TO A VERY NARROW ENVELOPE,
WITH MINIMAL CROSS- OR ALONG-TRACK UNCERTAINTY. THE JTWC FORECAST IS
PLACED NEAR THE MULTI-MODEL CONSENSUS MEAN AS WELL AS THE AI CONSENSUS
MEAN WITH HIGH CONFIDENCE. AFTER TAU 60, THE GUIDANCE BEGINS TO
DIVERGE RAPIDLY. AS DISCUSSED ABOVE, THE GFS, NAVGEM AND JGSM ALL
DEPART FROM THE TIGHTLY CONSTRAINED MODEL ENVELOPE, INITIALLY MOVING
SOUTHWESTWARD, SLOWING DOWN TO NEARLY QUASI-STATIONARY SPEEDS, AND
THEN RAPIDLY TURN NORTHWARD AFTER TAU 72, ENDING UP BETWEEN AMAMI
OSHIMA AND YAKUSHIMA BY TAU 120. THE REMAINDER OF THE DETERMINISTIC
MODELS (ECMWF, GALWEM, UKMET), THE GEFS, AND ECENS ENSEMBLE MEANS, AS
WELL AS ALL AVAILABLE AI MODEL TRACKERS, MOVE THE SYSTEM WESTWARD INTO
THE EAST CHINA SEA, WITH STEADILY DECREASING SPEED. THE JTWC FORECAST
IS PLACED NORTH OF THE ECMWF, BUT SOUTH OF THE GEFS AND ECENS MEANS,
CLOSE TO THE AI CONSENSUS MEAN. THE JTWC EXPERIMENTAL SUPER ENSEMBLE
SHOWS A TIGHT MEMBER ENVELOPE THROUGH TAU 72, WITH INCREASED MEMBER
DISPERSION THEREAFTER, WITH A FOCUS ON A NORTHWARD TURN AFTER TAU 96.
CONFIDENCE IN THE EXTENDED FORECAST IS MEDIUM IN LIGHT OF THE
INCREASED UNCERTAINTY IN THE ENSEMBLE MEMBERS AND RECENT SHIFT IN
SEVERAL OF THE MODEL TRACKERS. INTENSITY GUIDANCE IS FOR THE MOST PART
IN GOOD AGREEMENT. THE ONLY MODEL SHOWING INTENSIFICATION IS CTCX,
WHILE THE REMAINDER OF THE CONSENSUS DEPICTS A GRADUAL WEAKENING
THROUGH THE FORECAST PERIOD, SUPPORTING THE JTWC FORECAST WITH MEDIUM
CONFIDENCE.
FORECAST CONFIDENCE:
TRACK 00-72 HR: HIGH
TRACK 72-120 HR: MEDIUM
INTENSITY 00-72 HR: MEDIUM
INTENSITY 72-120 HR: LOW//
NNNN
Ensemble Track Ellipses
AI Model Track Forecasts
Multiplatform Tropical Cyclone MSLP and Maximum Winds
Digital Dvorak
Bias Correction of Subjective Dvorak
DVORAK ANALYSIS @0830 UTC
TPPN11 PGTW 040905
A. TYPHOON 12W (DOLPHIN)
B. 04/0830Z
C. 25.33N
D. 141.32E
E. ONE/GK2A
F. T6.0/6.0/D1.5/24HRS STT: S0.0/03HRS
G. IR/EIR
H. REMARKS: 01A/PBO EYE/ANMTN. WMG EYE SURROUNDED BY LG YIELDS AN
E# OF 5.0. ADDED 1.0 EYE ADJUSTMENT FOR B, TO YIELD A DT OF 6.0.
MET YIELDS 5.5. PT YIELDS 6.0. DBO DT.
I. ADDITIONAL POSITIONS:
04/0352Z 25.28N 142.33E AMS2
04/0748Z 25.40N 141.42E MMWI
BALMER
A. TYPHOON 12W (DOLPHIN)
B. 04/0830Z
C. 25.33N
D. 141.32E
E. ONE/GK2A
F. T6.0/6.0/D1.5/24HRS STT: S0.0/03HRS
G. IR/EIR
H. REMARKS: 01A/PBO EYE/ANMTN. WMG EYE SURROUNDED BY LG YIELDS AN
E# OF 5.0. ADDED 1.0 EYE ADJUSTMENT FOR B, TO YIELD A DT OF 6.0.
MET YIELDS 5.5. PT YIELDS 6.0. DBO DT.
I. ADDITIONAL POSITIONS:
04/0352Z 25.28N 142.33E AMS2
04/0748Z 25.40N 141.42E MMWI
BALMER
Platform: RCM-3 Acquisition Date: 2026-08-04 08:42:31 UTC
Platform: RCM-3
Acquisition Date: 2026-08-04 08:42:31 UTC
Storm Name: WP122026 / DOLPHIN
Storm ID: WP12
Storm Center Longitude: 141.200
Storm Center Latitude: 25.340
Incidence Angle (Degrees): 44.555
Quadrant 1 NE VMax (kts): 114.60
Quadrant 2 SE VMax (kts): 100.01
Quadrant 3 SW VMax (kts): 99.93
Quadrant 4 NW VMax (kts): 110.24
RMax (nmi): 8.00 - 12.00
Acquisition Date: 2026-08-04 08:42:31 UTC
Storm Name: WP122026 / DOLPHIN
Storm ID: WP12
Storm Center Longitude: 141.200
Storm Center Latitude: 25.340
Incidence Angle (Degrees): 44.555
Quadrant 1 NE VMax (kts): 114.60
Quadrant 2 SE VMax (kts): 100.01
Quadrant 3 SW VMax (kts): 99.93
Quadrant 4 NW VMax (kts): 110.24
RMax (nmi): 8.00 - 12.00
WESTERN PACIFIC: INVEST 94W TCFA ISSUED BY JTWC @0700 UTC
WTPN21 PGTW 040700
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 94W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 135 NM RADIUS OF 16.9N 119.4E 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 17 TO 22 KNOTS. METSAT IMAGERY AT 040600Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 16.9N 119.4E. THE SYSTEM IS
MOVING WESTWARD AT 02 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 94W) PREVIOUSLY LOCATED NEAR
17.7N 121.8E IS NOW LOCATED NEAR 16.9N 119.4E, APPROXIMATELY 63 NM
SOUTHWEST OF VIGAN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
DEPICTS AN OBSCURED NASCENT LOW LEVEL CIRCULATION CENTER (LLCC) ALONG
THE WESTERN COASTLINE OF LUZON THAT FEATURES CONVECTIVE BANDING ALONG
THE SOUTH-WESTERN PERIPHERY OF THE CIRCULATION. STRONG WEST-
SOUTHWESTERLY FLOW IS CLEARLY SEEN FLOWING INTO WESTERN LUZON, ROUGHLY
FROM LINGAYEN GULF SOUTHWARDS. ENVIRONMENTAL ANALYSIS REVEALS FAVORABLE
CONDITIONS FOR TROPICAL CYCLONE DEVELOPMENT, AS THE SYSTEM IS POSITIONED
WITHIN A POCKET OF LOW VERTICAL WIND SHEAR (10-15KTS), WARM SEA SURFACE
(29 TO 30 C), AND GOOD EQUATORWARD OUTFLOW. GFS IS THE ONLY
DETERMINISTIC MODEL CURRENTLY DEPICTING CONSOLIDATION OF 94W IN THE NEXT
24 HOURS, SHOWING THE WESTERLY WINDS SOUTH OF LINGAYEN GULF QUICKLY
TURNING NORTHWARD DUE TO TERRAIN FORCING, AND WRAPPING INTO THE QUICKLY
DEVELOPING CENTER. MEANWHILE, THE ECMWF KEEPS THE CENTER CLOSER TO SHORE
AND DOES NOT CONSOLIDATE THE CIRCULATION OR WRAP THE SOUTHERLY WINDS UP
THE EAST SIDE DUE TO THE PROXIMITY TO LAND. ENSEMBLE MODELS BOTH AGREE
ON THE FURTHER DEVELOPMENT INTO A TROPICAL DEPRESSION AND A GENERAL
EASTWARD TRACK BACK OVER LUZON AFTER 24-36 HOURS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 17 TO 22 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1006 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
050700Z.//
NNNN
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 94W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 135 NM RADIUS OF 16.9N 119.4E 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 17 TO 22 KNOTS. METSAT IMAGERY AT 040600Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 16.9N 119.4E. THE SYSTEM IS
MOVING WESTWARD AT 02 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 94W) PREVIOUSLY LOCATED NEAR
17.7N 121.8E IS NOW LOCATED NEAR 16.9N 119.4E, APPROXIMATELY 63 NM
SOUTHWEST OF VIGAN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
DEPICTS AN OBSCURED NASCENT LOW LEVEL CIRCULATION CENTER (LLCC) ALONG
THE WESTERN COASTLINE OF LUZON THAT FEATURES CONVECTIVE BANDING ALONG
THE SOUTH-WESTERN PERIPHERY OF THE CIRCULATION. STRONG WEST-
SOUTHWESTERLY FLOW IS CLEARLY SEEN FLOWING INTO WESTERN LUZON, ROUGHLY
FROM LINGAYEN GULF SOUTHWARDS. ENVIRONMENTAL ANALYSIS REVEALS FAVORABLE
CONDITIONS FOR TROPICAL CYCLONE DEVELOPMENT, AS THE SYSTEM IS POSITIONED
WITHIN A POCKET OF LOW VERTICAL WIND SHEAR (10-15KTS), WARM SEA SURFACE
(29 TO 30 C), AND GOOD EQUATORWARD OUTFLOW. GFS IS THE ONLY
DETERMINISTIC MODEL CURRENTLY DEPICTING CONSOLIDATION OF 94W IN THE NEXT
24 HOURS, SHOWING THE WESTERLY WINDS SOUTH OF LINGAYEN GULF QUICKLY
TURNING NORTHWARD DUE TO TERRAIN FORCING, AND WRAPPING INTO THE QUICKLY
DEVELOPING CENTER. MEANWHILE, THE ECMWF KEEPS THE CENTER CLOSER TO SHORE
AND DOES NOT CONSOLIDATE THE CIRCULATION OR WRAP THE SOUTHERLY WINDS UP
THE EAST SIDE DUE TO THE PROXIMITY TO LAND. ENSEMBLE MODELS BOTH AGREE
ON THE FURTHER DEVELOPMENT INTO A TROPICAL DEPRESSION AND A GENERAL
EASTWARD TRACK BACK OVER LUZON AFTER 24-36 HOURS. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 17 TO 22 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 1006 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
050700Z.//
NNNN
WESTERN PACIFIC: INVEST 96W
