|
|
楼主 |
发表于 2025-11-26 10:13
|
显示全部楼层
JTWC/33W/#06/11-26 00Z Prognostic Reasoning
WDPN31 PGTW 260300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 33W (KOTO) WARNING NR
006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 12.5N 117.6E
INITIAL INTENSITY: 55 KTS
GEOGRAPHIC REFERENCE: 235 NM WEST-SOUTHWEST OF MANILA,
PHILIPPINES
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 17 KTS
SIGNIFICANT WAVE HEIGHT: 24 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A RAGGED AND
RELATIVELY DISORGANIZED CENTRAL DENSE OVERCAST (CDO) FEATURE, WITH
ISOLATED VORTICAL HOT TOWERS AND OVERSHOOTING TOPS, WHICH ARE
STARTING TO SHOW SIGNS OF ORGANIZING AROUND THE LIKELY VORTEX. A
252254Z SSMIS 91GHZ MICROWAVE IMAGE SUGGESTS A NASCENT MICROWAVE
EYE FEATURE, WITH DEEP CONVECTION TO THE WEST AND SOUTHEAST OF THE
CENTER, STARTING TO WRAP IN TOWARDS THE CENTER. HOWEVER, THERE
APPEARS TO BE A FAIR AMOUNT OF VORTEX TILT TOWARDS THE NORTH WITH
HEIGHT, BASED ON A COMPARISON OF THE 91GHZ AND 37GHZ CHANNELS AND
CONFIRMED BY HAFS-A MODEL CROSS-SECTIONS. THE INITIAL POSITION IS
ASSESSED WITH MEDIUM CONFIDENCE DUE TO THE WIDE DISPERSAL BETWEEN
THE KNES, RJTD AND PGTW FIX POSITIONS. THE INITIAL INTENSITY IS
ASSESSED WITH HIGH CONFIDENCE, BASED ON THE T3.5 DVORAK CURRENT
INTENSITY ESTIMATES FROM BOTH PGTW AND KNES ALONG WITH THE CIMSS
ADT AND AIDT ESTIMATES IN THE 50-59 KNOT RANGE. ENVIRONMENTAL
CONDITIONS REMAIN FAVORABLE, WITH DEEP-LAYER SHEAR STEADILY
DECREASING, OUTFLOW ALOFT IMPROVING AND SSTS REMAINING QUITE WARM.
INITIAL WIND RADII BASIS: PERSISTENCE
CURRENT STEERING MECHANISM: SOUTHWESTERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED OVER THE PHILIPPINE SEA.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T3.5 - 55 KTS
RJTD: T3.0 - 45 KTS
RCTP: T3.0 - 45 KTS
KNES: T3.5 - 55 KTS
CIMSS SATCON: 48 KTS AT 252030Z
CIMSS ADT: 59 KTS AT 260030Z
CIMSS AIDT: 48 KTS AT 260000Z
CIMSS D-MINT: 46 KTS AT 252253Z
CIMSS D-PRINT: 47 KTS AT 260020Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 28-29 CELSIUS
OUTFLOW: STRONG POLEWARD AND EQUATORWARD
ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
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: TROPICAL STORM (TS) 33W HAS SPED UP
CONSIDERABLY OVER THE PAST SIX HOURS, NOW TRUCKING
WEST-NORTHWESTWARD AT 17 KNOTS, AS THE STEERING GRADIENT IS NOW
REACHING ITS STRONGEST. FROM THIS POINT FORWARD HOWEVER, THE SYSTEM
IS EXPECTED TO BEGIN A STEADY SLOW-DOWN AS THE TRAJECTORY FLATTENS
OUT A BIT, TO A MORE WESTWARD TRACK AS THE STEERING RIDGE OVER THE
PHILIPPINE SEA MOVES EASTWARD AND THE SYSTEM BEGINS TO MOVE INTO A
WEAK AND COMPETING STEERING PATTERN. BY TAU 24, THE SYSTEM WILL
SLOW DOWN TO BELOW FIVE KNOTS FORWARD SPEED AS IT RUNS INTO THE
EASTERN SIDE OF A BAND OF STRONG NORTHEASTERLY FLOW ASSOCIATED WITH
A COLD-SURGE STREAMING SOUTHWARD INTO THE SOUTH CHINA SEA (SCS) AND
SIMULTANEOUSLY GETS TRAPPED BETWEEN RIDGING OVER THAILAND, OVER THE
PHILIPPINE SEA AND A NEAR EQUATORIAL RIDGE (NER) TO THE SOUTH.
TRACK SPEEDS WILL CONTINUE TO DECREASE AFTER TAU 24, WITH THE
SYSTEM BECOMING QUASI-STATIONARY AFTER TAU 48. THE SYSTEM WILL
LIKELY DRIFT TOWARDS THE SOUTHWEST, THEN SHIFT TO A MORE NORTHWARD
DRIFT, ALBEIT AT VERY SLOW SPEEDS, AFTER TAU 72, AS THE RIDGE TO
SOUTH BUILDS NORTHWARD AND ENHANCES THE STEERING GRADIENT ALONG THE
EASTERN FLANK OF TS 33W. BY THE END OF THE FORECAST PERIOD, THE
SYSTEM WILL BEGIN TURNING WESTWARD AS THE RIDGE TO THE NORTHWEST
STRENGTHENS AND TAKES OVER THE PRIMARY STEERING INFLUENCE. IN
TERMS OF INTENSITY, THE SYSTEM HAS A SHORT WINDOW OF 24 HOURS OF
FAVORABLE CONDITIONS TO CONTINUE TO INTENSIFY, AND IS EXPECTED TO
REACH A PEAK INTENSITY OF 70 KNOTS BEFORE THE DOOR SLAMS SHUT AND
CONDITIONS RAPIDLY DETERIORATE, WITH RAPIDLY INCREASING SHEAR BEING
THE PRIMARY NEGATIVE DRIVER. THE GREATLY ENHANCED SHEAR WILL LEAD
TO A VORTEX DECOUPLING AND DECAPITATION, AND THE SYSTEM WILL
QUICKLY WEAKEN DOWN TO ABOUT 45 KNOTS AS IT DRIFTS SLOWLY ACROSS
THE SCS. THE WINDOW OF HIGH SHEAR WILL BE SHORT HOWEVER AND SHEAR
WILL DECREASE AGAIN AFTER TAU 72, AND THE SYSTEM SEPARATES FROM THE
COLD SURGE FLOW, ALLOWING FOR A RENEWED VORTEX ALIGNMENT AND
REINTENSIFICATION AFTER TAU 96.
MODEL DISCUSSION: DETERMINISTIC TRACK GUIDANCE HAS COME INTO
SLIGHTLY BETTER AGREEMENT SINCE THE PREVIOUS MODEL RUN, THOUGH IT
REMAINS HIGHLY UNCERTAIN AFTER TAU 48 IN PARTICULAR. UP TO TAU 48,
ALL CONSENSUS MEMBERS ARE IN TIGHT AGREEMENT, BOTH IN THE ALONG-
AND CROSS-TRACK SENSE, BUT THINGS GET A BIT SQUIRRELLY AFTER THIS
POINT. THE MAJORITY OF THE JTWC MODIFIED CONSENSUS (WITHOUT THE
UKMET, UKMET ENSEMBLE AND GALWEM) MEMBERS VERY SLOWLY TRACK THE
SYSTEM SOUTHWESTWARD THEN NORTHWARD THROUGH THE END OF THE FORECAST
PERIOD, WHILE THE ECMWF-AIFS AND GDM MEAN TURN THE SYSTEM NORTHWEST
AT ABOUT DOUBLE THE SPEED. THE RESULT IS A FAIRLY WIDE CROSS-TRACK
SPREAD BETWEEN THE COAST OF VIETNAM AND THE CENTRAL SCS. THE JTWC
FORECAST IS POSITIONED JUST WEST OF THE CONSENSUS MEAN AFTER TAU
72, WITH LOW CONFIDENCE. INTENSITY GUIDANCE REMAINS IN GOOD OVERALL
AGREEMENT, WITH ALL MODELS INDICATING A PEAK OCCURRING AT TAU 24,
WITH A RANGE BETWEEN 60-75 KNOTS, FOLLOWED BY A STEADY WEAKENING
AND THEN REINTENSIFICATION AFTER TAU 96. SEVERAL RI AIDS CONTINUE
TO BE TRIPPED WITH THIS CYCLE, BUT WITH THE LIMITED WINDOW OF
OPPORTUNITY FOR INTENSIFICATION, THE MORE AGGRESSIVE RIPA, RICN AND
RIDE MEMBERS (PEAKING AT 95 KNOTS) ARE CONSIDERED UNLIKELY TO
OCCUR. THE JTWC FORECAST IS PLACED ON THE HIGHER END OF THE
ENVELOPE ACROSS THE MAJORITY OF THE FORECAST, WITH MEDIUM
CONFIDENCE.
FORECAST CONFIDENCE:
TRACK 00-72 HR: MEDIUM
TRACK 72-120 HR: LOW
INTENSITY 00-72 HR: MEDIUM
INTENSITY 72-120 HR: MEDIUM//
NNNN
|
本帖子中包含更多资源
您需要 登录 才可以下载或查看，没有账号？立即注册
×
|
楼主: ygsj24
发表于 2025-11-26 09:48
