WESTERN PACIFIC:Typhoon 06W(JANGMI) forecast to peak at CAT 2 US within 36h and track very close to OKINAWA by 48h/301030 UTC /

WDPN31 PGTW 300900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 06W (JANGMI) WARNING NR 013//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
   INITIAL POSITION: 18.3N 129.6E
   INITIAL INTENSITY: 65 KTS
   GEOGRAPHIC REFERENCE: 502 NM SOUTH-SOUTHEAST OF KADENA AB
   MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 11 KTS
   SIGNIFICANT WAVE HEIGHT: 33 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A BROAD,
IRREGULAR LOW LEVEL CIRCULATION CENTER (LLCC), WITH A WAVENUMBER 4
ASYMMETRY PATTERN. THE MSI SHARPLY DEPICTS AT LEAST THREE
WELL-DEFINED MESOVORTICES ALONG THE INNER EDGE OF THE EYEWALL, WITH
A WEAKER FOURTH MESOVORTEX, IMPARTING A QUASI-QUADRILATERAL EYEWALL
GEOMETRY. THE RADIUS OF MAXIMUM WINDS (RMW) AND EYEWALL DIAMETER HAVE
DECREASED SLIGHTLY, FROM 70 NM TO 60 NM, BASED ON ANALYSIS OF EARLIER 
SYNTHETIC APERTURE RADAR (SAR) DATA AND CURRENT MSI OBSERVATIONS. THE 
INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE, PLACED IN THE 
CENTROID OF THE MESOVORTICES SEEN IN THE ANIMATED MSI. THE INITIAL 
INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE, BASED ON A BLEND OF 
SUBJECTIVE AGENCY DVORAK CURRENT INTENSITY ESTIMATES, INFORMED BY 
CIMSS SATCON AND D-PRINT GUIDANCE. CIMSS ADT AND AIDT ESTIMATES ARE 
SIGNIFICANTLY UNDERESTIMATED, DUE TO THEIR UTILIZATION OF THE CURVED 
BAND METHOD RATHER THAN THE EYE TECHNIQUE EMPLOYED BY THE OTHER 
AGENCIES, AS WELL AS THE LARGE SIZE OF THE SYSTEM. ENVIRONMENTAL 
CONDITIONS ARE GENERALLY FAVORABLE FOR ADDITIONAL INTENSIFICATION, BY 
LOW DEEP-LAYER VERTICAL WIND SHEAR (VWS), WARM SEA SURFACE 
TEMPERATURES (SSTS), AND MODERATE RADIAL OUTFLOW. HOWEVER, THE BROAD 
MORPHOLOGY OF THE INNER CORE, THE WAVENUMBER-4 ASYMMETRIES, AND THE 
PATHWAY OVER A POCKET OF LOW (40-50 KJ PER SQUARE CENTIMETER) OCEAN 
HEAT CONTENT (OHC) WILL ACT AS A PRIMARY CONSTRAINT ON THE 
INTENSIFICATION RATE.

INITIAL WIND RADII BASIS: SAR DATA 

CURRENT STEERING MECHANISM: SOUTHWESTERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) POSITIONED NEAR IWO TO. 

AGENCY DVORAK AND AUTOMATED FIXES: 
   PGTW: T4.0 - 65 KTS
   RJTD: T3.0 - 45 KTS
   RCTP: T3.5 - 55 KTS
   KNES: T4.0 - 65 KTS
   CIMSS SATCON: 57 KTS AT 300630Z
   CIMSS ADT: 31 KTS AT 300630Z
   CIMSS AIDT: 41 KTS AT 300630Z
   CIMSS D-MINT: 53 KTS AT 300408Z
   CIMSS D-PRINT: 65 KTS AT 300600Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
   VWS: 10-15 KTS
   SST: 29-30 CELSIUS
   OUTFLOW: MODERATE RADIAL

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: TYPHOON (TY) 06W (JANGMI) CONTINUES ITS
NORTHWESTWARD TRAJECTORY ALONG THE SOUTHWESTERN PERIMETER OF THE
DEEP-LAYER STR CENTERED NEAR IWO TO. NO SIGNIFICANT CHANGE IN THE
OVERALL STEERING PATTERN IS EXPECTED OVER THE NEXT 24 TO 36 HOURS.
BEGINNING NEAR TAU 36, THE SYSTEM WILL DECELERATE IN FORWARD 
TRANSLATION SPEED AS IT APPROACHES THE STR AXIS AND TURNS NORTHWARD 
TOWARDS OKINAWA. TY 06W IS FORECAST TO ROUND THE RIDGE AXIS JUST 
SOUTH OF OKINAWA NEAR 010600Z, THEN BEGIN A STEADY ACCELERATION 
TOWARDS THE NORTHEAST THROUGH TAU 96. THE FORECAST CALLS FOR THE 
CENTER OF TY 06W TO TRACK JUST WEST OF THE NORTHERN RYUKYU ISLAND 
CHAIN, THEN TURN NORTHEASTWARD TO THE SOUTH OF KYUSHU AND REMAIN 
OFFSHORE OF SHIKOKU AND HONSHU THROUGH THE FORECAST PERIOD, THOUGH A 
CLOSE APPROACH TO THE SOUTHERN BOSO PENINSULA IS EXPECTED NEAR TAU 
96. A SLIGHT DECELERATION IS EXPECTED BY THE END OF THE FORECAST 
PERIOD AS THE STR WEAKENS AND DISPLACES SOUTHWESTWARD, ATTENUATING 
THE STEERING GRADIENT. REGARDING INTENSITY, THE SYSTEM IS 
CONSOLIDATING AT A GRADUAL RATE, WITH A STEADY REDUCTION IN RMW 
OBSERVED OVER THE LAST 10 HOURS. HOWEVER, THE SYSTEM RETRAINS A 
MULTI-VORTEX ASYMMETRY, WHICH WILL INHIBIT RAPID CONSOLIDATION OF THE 
INNER CORE. THE MAJORITY OF THE MESOSCALE MODELS INDICATE CORE 
CONSOLIDATION WITHIN THE NEXT 24 TO 36 HOURS; HOWEVER, BY THIS 
TIMEFRAME, THE SYSTEM WILL BE TRANSITIONING OVER A SHARP OCEANIC 
THERMAL GRADIENT, THEREBY RAPIDLY DIMINISHING THE THERMODYNAMIC 
SUPPORT REQUISITE FOR RAPID INTENSIFICATION. NONETHELESS, AN 
ADDITIONAL 15-20 KNOTS OF INTENSIFICATION OVER THE NEXT 24 HOURS IS 
REASONABLE PRIOR TO THE SYSTEM ENCOUNTERING COOLER WATERS. TY 06W 
WILL THEREFORE REACH A PEAK INTENSITY OF 85 KNOTS BY TAU 24, THEN 
MAINTAIN INTENSITY FOR APPROXIMATELY 12 HOURS BEFORE COMMENCING A 
GRADUAL WEAKENING TREND THROUGH THE REMAINDER OF THE FORECAST. THE 
SYSTEM WILL BEGIN EXTRATROPICAL TRANSITION (ETT) AS IT APPROACHES ITS 
CLOSEST POINT OF APPROACH (CPA) TO YOKOSUKA, AND COMPLETE TRANSITION 
AS A STORM-FORCE EXTRATROPICAL LOW BY TAU 120.

MODEL DISCUSSION: THE PHYSICS-BASED MODELS AND THE AI-BASED MODELS
HAVE BEGUN TO CONVERGE ON A COMMON TRACK SOLUTION, WITH THE DISTINCT 
BIFURCATIONS OBSERVED IN EARLIER MODEL RUNS NOW RESOLVED. THE AI-
BASED MODELS ARE PRIMARILY POSITIONED ALONG THE EASTERN EDGE OF THE 
ENVELOPE, WHILE THE DETERMINISTIC NWP MODELS OCCUPY THE WESTERN SIDE 
OF THE CONSENSUS MEAN. THROUGH THE CPA TO OKINAWA (TAU 48), CROSS-
TRACK SPREAD HAS DECREASED TO JUST 70 NM BETWEEN THE GFS AND UKMET 
ENSEMBLE MEANS ON THE WEST SIDE, AND THE EC-AIFS AND GDM FNV3 ON THE 
EAST SIDE, WITH MINIMAL ALONG-TRACK SPREAD. BY TAU 72, CROSS-TRACK 
SPREAD INCREASES TO 100 NM, AND ALONG-TRACK UNCERTAINTY BEGINS TO 
MANIFEST BETWEEN THE FASTER AI-BASED MODELS AND SLOWER DETERMINISTIC 
GUIDANCE. BY THE TERMINATION OF THE FORECAST PERIOD, CROSS-TRACK 
SPREAD INCREASES TO NEARLY 200 NM, WHILE ALONG-TRACK SPREAD INCREASES 
TO 250 NM BETWEEN THE LAGGING GFS AND ACCELERATED AI-BASED GUIDANCE. 
THE JTWC FORECAST IS POSITIONED NEAR THE EXPERIMENTAL SUPER-ENSEMBLE 
(A COHORT OF FIVE ENSEMBLE MODELS) TRACKER AND SLIGHTLY FASTER THAN 
THE TRADITIONAL CONSENSUS MEAN, WITH A HIGH DEGREE OF FORECAST 
CONFIDENCE. INTENSITY GUIDANCE REMAINS DIVERGENT. THE MESOSCALE 
MODELS (HWRF, HAFS-A, COTC, CTCX) INDICATE MINIMAL ADDITIONAL 
INTENSIFICATION, PEAKING BETWEEN 70-80 KNOTS. THE DECAY-SHIPS 
GUIDANCE PEAKS AT 85 KNOTS, IN AGREEMENT WITH THE GDM FNV3 MODEL. 
ADDITIONALLY, MULTIPLE RAPID INTENSIFICATION (RI) AIDS CONTINUE TO 
TRIGGER, BUT THE THERMODYNAMIC AND STRUCTURAL ENVIRONMENT DOES NOT 
SUPPORT RI CONDITIONS. IT IS HIGHLY IMPROBABLE THAT THE SYSTEM 
POSSESSES THE CAPACITY TO ATTAIN 110-120 KNOTS IN THE NEXT 36 HOURS 
AS INDICATED BY THE RI GUIDANCE. THE JTWC FORECAST IS PLACED FIVE 
KNOTS HIGHER THAN THE CONSENSUS MEAN THROUGH THE FORECAST PERIOD, 
WITH MEDIUM CONFIDENCE. 

FORECAST CONFIDENCE:
   TRACK 00-72 HR: HIGH
   TRACK 72-120 HR: HIGH
   INTENSITY 00-72 HR: MEDIUM
   INTENSITY 72-120 HR: MEDIUM//
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Platform: SENTINEL-1A
Acquisition Date: 2026-05-29 21:13:22 UTC
Storm Name: WP062026 / JANGMI
Storm ID: WP06
Storm Center Longitude: 130.681
Storm Center Latitude: 16.866
Incidence Angle (Degrees): 31.395
Quadrant 1 NE VMax (kts): 70.69
Quadrant 2 SE VMax (kts): 66.91
Quadrant 3 SW VMax (kts): 57.42
Quadrant 4 NW VMax (kts): 62.05
RMax (nmi): 54.00 - 82.00