ZCZC MIATCDEP1 ALL TTAA00 KNHC DDHHMM Hurricane Trudy Discussion Number 17 NWS National Hurricane Center Miami FL EP212026 900 AM CST Sat Oct 17 2026 Trudy is slowly becoming better organized. The hurricane is producing a large central dense overcast with cloud tops colder than -80C, and curved bands of overshooting tops in the CDO indicate an eyewall is present underneath it. The various satellite intensity estimates are starting to increase, but not enough yet to support raising the intensity. Thus, the initial intensity remains 80 kt. The hurricane is moving a little faster toward the northwest, 325/9 kt. A continued northwestward motion is expected during the next day or so as a weak low- to mid-level ridge builds over eastern Mexico. This general motion should continue for the next 36 h or so, bringing the center of Trudy very close to the coast of west-central Mexico. Thereafter, as Trudy weakens and becomes steered mainly by low-level flow, a turn toward the west and west-northwest is expected, taking the cyclone away from the coast. The new track forecast has only minor adjustments from the previous forecast, with the center making its closest approach to the coast of Mexico around 36-48 h. Now that Trudy is over water with a higher oceanic heat content, some strengthening is possible. However, moderate vertical shear, dry air entrainment, and increasing land interaction could limit how much strengthening may occur. After 24 h or so, increasing southwesterly shear and decreasing mid-level moisture near the cyclone are likely to cause steady to rapid weakening even when the center would be moving away from the coast of Mexico. Current expectations are that the system will stop producing convection between 72-96 h and decay to a remnant low pressure, and the global models forecast the circulation to weaken to a trough by 120 h. The new intensity forecast has some tweaks from the previous forecast, and it lies near the upper edge of the intensity guidance envelope. KEY MESSAGES: 1. Trudy could strengthen some during the next 12 hours or so as it approaches the coast of southwestern and west-central Mexico this weekend, bringing an increasing risk of storm surge, damaging winds, and flooding rain. Hurricane Warnings and Watches, as well as Tropical Storm Warnings and Watches, are currently in effect for portions of the coast, and additional watches and warnings may be required. 2. Heavy rainfall associated with Trudy will impact the southwest Mexican coast between Guerrero and Nayarit through the weekend. This rainfall may produce life-threatening flooding and mudslides this weekend along and near the southwest Mexican coast in Michoacán, Colima, and Jalisco, especially in areas along steep terrain. 3. Large swells are affecting portions of the coast of southwestern Mexico and will spread northward through the weekend, causing life-threatening surf and rip current conditions. FORECAST POSITIONS AND MAX WINDS INIT 17/1500Z 16.6N 103.9W 80 KT 90 MPH 12H 18/0000Z 17.7N 104.8W 90 KT 105 MPH 24H 18/1200Z 19.1N 105.7W 90 KT 105 MPH 36H 19/0000Z 20.1N 106.4W 85 KT 100 MPH 48H 19/1200Z 20.7N 107.0W 65 KT 75 MPH 60H 20/0000Z 20.9N 107.5W 45 KT 50 MPH 72H 20/1200Z 20.9N 108.2W 35 KT 40 MPH 96H 21/1200Z 21.7N 109.4W 25 KT 30 MPH...POST-TROP/REMNT LOW 120H 22/1200Z...DISSIPATED $$ Forecaster Beven NNNN

WDPN32 PGTW 171500 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TYPHOON 29W (CHAMPI) WARNING NR 013// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 12.6N 146.1E INITIAL INTENSITY: 120 KTS GEOGRAPHIC REFERENCE: 96 NM SOUTHEAST OF ANDERSEN AFB MOVEMENT PAST 6 HOURS: WESTWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 42 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: THE OVERALL STRUCTURE OF TY 29W IN ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY HAS DETERIORATED OVER THE PAST SIX HOURS, AS THE THE PREVIOUSLY CLOUD-FREE, PINHOLE EYE HAS FILLED IN DUE TO AN ONGOING EYEWALL REPLACEMENT CYCLE (ERC). THE EYE REMAINS DETECTABLE IN EIR IMAGERY, AND APPEARS TO BE SLIGHTLY LARGER THAN SIX HOURS AGO. HOWEVER, THE EYE TEMPERATURES ARE VERY COLD (APPROXIMATELY -50C). ANIMATED RADAR IMAGERY FROM GUAM SHOWS THAT THE EYE TOOK A A TEMPORARY WEST-SOUTHWESTWARD TROCHOIDAL JOG OVER THE PAST SIX HOURS; HOWEVER, THE INTEGRATED MOTION VECTOR REMAINS STABLE AT 280 DEGREES AT 14 KNOTS BASED ON THE BEST TRACK. OVER THE PAST TWO HOURS, THE SYSTEM HAS RESUMED A WEST-NORTHWESTWARD HEADING AMID TROCHOIDAL OSCILLATION. RADAR DATA CLEARLY RESOLVES A CONCENTRIC EYEWALL MORPHOLOGY, HIGHLIGHTED BY A THICKENING INNER EYEWALL, A DISTINCT RADAR MOAT, AND A SECONDARY OUTER EYEWALL SITUATED APPROXIMATELY 30 NM DISTANT FROM THE GEOMETRIC CENTER-STRONG STRUCTURAL SIGNATURES CONFIRMING ERC PROGRESSION. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE BASED ON THE RADAR EYE FIXES. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE. ALTHOUGH THE EYE HAS FILLED WITHIN THE PAST TWO HOURS, THE SYSTEM LIKELY ATTAINED PEAK INTENSITY IMMEDIATELY PRIOR TO ERC INITIATION, WITH SURFACE WIND ENERGETICS TEMPORARILY LAGGING THE STRUCTURAL EVOLUTION. THIS IS REINFORCED BY CONCURRENT SUBJECTIVE AND OBJECTIVE SATELLITE ESTIMATES, WHICH CONVERGE AT 120 KNOTS. THE ENVIRONMENT REMAINS HIGHLY CONDUCIVE INDEPENDENT OF CORE-SCALE ERC DYNAMICS, SUPPORTED BY LOW DEEP-LAYER VWS, EXTREMELY WARM SSTS (29- 30C), AND VIGOROUS RADIAL OUTFLOW ALOFT. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SOUTHERN PERIPHERY OF A DEEP-LAYER SUBTROPICAL RIDGE (STR) FAR TO THE NORTH. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T6.5 - 127 KTS RJTD: T6.0 - 115 KTS CIMSS ADT: 112 KTS AT 171130Z CIMSS AIDT: 122 KTS AT 171130Z CIMSS D-MINT: 120 KTS AT 171033Z CIMSS D-PRINT: 122 KTS AT 171130Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: HIGHLY FAVORABLE VWS: 10-15 KTS SST: 29-30 CELSIUS OUTFLOW: STRONG RADIAL OTHER FACTORS: EQUATORWARD OUTFLOW CHANNEL; EYEWALL REPLACEMENT CYCLE (ERC). ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TYPHOON (TY) 29W IS TRACKING WESTWARD IN THE AGGREGATE, ALTHOUGH ERRATIC TROCHOIDAL MOTION IS PROJECTED TO PERSIST PENDING COMPLETION OF THE ERC. THE EXACT FREQUENCY AND AMPLITUDE OF THIS MOTION, WHICH REMAIN HIGHLY UNCERTAIN, WILL GOVERN THE PRECISE CPA AND TRACK GEOMETRY WHEN PASSING GUAM. THE CYCLONE WILL TRANSIT THE SOUTHERN TIP OF GUAM WITHIN THE NEXT SIX TO EIGHT HOURS. THE CORE WILL THEN VEER PROGRESSIVELY NORTHWESTWARD AS THE STR TO THE NORTH SLIDES EASTWARD, REPLACED BY A SECONDARY HIGH-PRESSURE CELL TRANSLATING RAPIDLY WEST-TO-EAST TO THE NORTH. BY TAU 96, THE STR WILL POSITION SOUTHEAST OF HONSHU, DEVELOPING A BROAD WEAKNESS OVER THE EAST CHINA SEA. CONSEQUENTLY, TY 29W WILL DECELERATE SHARPLY WHILE MAINTAINING A GENERAL NORTHWESTWARD HEADING PAST TAU 96 AS THE STEERING GRADIENT RELAXES. REGARDING INTENSITY: THE ACTIVE ERC INTRODUCES COMPETING THERMODYNAMIC AND STRUCTURAL INFLUENCES. SP…

WDPS31 PGTW 170900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 01P (WATI) WARNING NR 003// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 13.2S 163.2W INITIAL INTENSITY: 60 KTS GEOGRAPHIC REFERENCE: 442 NM EAST OF PAGO PAGO MOVEMENT PAST 6 HOURS: SOUTH-SOUTHEASTWARD AT 12 KTS SIGNIFICANT WAVE HEIGHT: 24 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A COMPACT INNER CORE OF DEEP CONVECTION WITH SLIGHTLY ASYMMETRIC SPIRAL BANDING FEATURES WRAPPING CONCENTRICALLY INTO AN OBSCURED LOW-LEVEL CIRCULATION CENTER (LLCC). A 170441Z WSF-M COLOR-ENHANCED 37GHZ MICROWAVE PASS REVEALED A WELL-DEFINED MICROWAVE EYE SIGNATURE, CHARACTERIZED BY A CYAN RING ENCIRCLING THE EYE AND DEEP CONVECTIVE CORES ALONG THE WESTERN AND NORTHERN FLANKS OF THE INNER CORE. THE INITIAL POSITION IS ASSESSED WITH HIGH CONFIDENCE, DERIVED FROM A SHORT-RANGE EXTRAPOLATION OF THE MICROWAVE EYE SIGNATURE. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE, HEDGED SLIGHTLY HIGHER THAN SUBJECTIVE AGENCY DVORAK FIXES (35-55 KTS) IN DEFERENCE TO THE CIMSS D-PRINT ESTIMATE (60 KTS), WHICH IS DEEMED MORE REPRESENTATIVE OF THE CONSOLIDATED CORE. ENVIRONMENTAL CONDITIONS ARE FAVORABLE FOR CONTINUED DEVELOPMENT, CHARACTERIZED BY WEAK DEEP-LAYER VERTICAL WIND SHEAR (VWS), WARM SEA SURFACE TEMPERATURES (SSTS), AND ROBUST POLEWARD OUTFLOW ALOFT. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: SOUTHWESTERN PERIPHERY OF A DEEP-LAYER SUBTROPICAL RIDGE (STR) TO THE NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.5 - 55 KTS PHFO: T2.5 - 35 KTS NFFN: T3.5 - 55 KTS CIMSS SATCON: 54 KTS AT 170740Z CIMSS ADT: 45 KTS AT 170540Z CIMSS AIDT: 42 KTS AT 170540Z CIMSS D-MINT: 46 KTS AT 170443Z CIMSS D-PRINT: 60 KTS AT 170710Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 0-5 KTS SST: 27-28 CELSIUS OUTFLOW: STRONG POLEWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: LOW 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 01P (WATI) EXHIBITED ERRATIC, LOOPING MOTION EARLIER IN THE DAY TODAY, BUT SINCE 00Z, HAS STEADIED UP ON A SOUTHEASTWARD TRAJECTORY BASED ON MULTIPLE MICROWAVE IMAGE PASSES. THE SYSTEM IS FORECAST TO ACCELERATE SOUTHEASTWARD ALONG THE SOUTHWESTERN FLANK OF THE STR THROUGHOUT THE ENTIRETY OF THE FORECAST PERIOD. REGARDING INTENSITY: TC 01P RESIDES WITHIN A CONDUCIVE ENVIRONMENT AND IS PROJECTED TO INTENSIFY STEADILY, REACHING A PEAK INTENSITY OF 75 KNOTS NEAR TAU 24. SHOULD INNER-CORE CONSOLIDATION ACCELERATE RAPIDLY, AN ONSET OF RAPID INTENSIFICATION (RI) REMAINS A POSSIBILITY, POTENTIALLY DRIVING PEAK SURFACE WINDS TOWARD 80-85 KNOTS. BY TAU 24, HOWEVER, DEEP-LAYER VWS IS PROJECTED TO INCREASE SHARPLY, INITIATING A WEAKENING TREND THAT WILL PERSIST THROUGH THE BALANCE OF THE FORECAST. TC 01P WILL PASS SOUTH OF THE 26C ISOTHERM WITHIN 36 HOURS, AND THIS WILL ACCELERATE THE DECAY RATE. BY TAU 60, THE CYCLONE WILL BEGIN TO INTERACT WITH A BAROCLINIC ZONE TO THE SOUTH, PHASING WITH THE POLAR JET STREAM TO INITIATE FRONTOGENESIS AND MARKING THE START OF EXTRATROPICAL TRANSITION (ETT). COMPLETED TRANSITION TO A COLD-CORE GALE IS FORECAST NLT TAU 72. MODEL DISCUSSION: TRACK GUIDANCE IS IN STRONG AGREEMENT ON THE OVERALL TRACK, WITH ALL CONSENSUS MEMBERS SUPPORTING A SOUTHEASTWARD TRACK THROUGH THE FORECAST PERIOD. CROSS-TRACK SPREAD GRADUALLY INCREASES TO 300 NM BY TAU 120. GALWEM DEFINES THE WESTERN (INNER) PERIPHERY OF THE GUIDANCE ENVELOPE, WHILE THE DETERMINISTIC GFS COVERS THE EASTERN BOUNDARY. THE AI MODELS, DETERMINISTIC ECMWF, …