阿拉伯海北部低压ARB 02(03A) 热带气旋档案

CMG ygsj24 2022-8-12 02:00 870






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IO, 98, 2022081112, , BEST, 0, 222N, 695E, 20, 990, DB,
最后于 2022-8-15 05:40 被ygsj24编辑 ,原因:
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  • ygsj24 CMG
    0 引用 2
    IO, 98, 2022081018,   , BEST,   0, 220N,  721E,  15,  991, DB,   0,    ,    0,    0,    0,    0,    0,    0,   0,   0,   0,   A,   0,    ,   0,   0,     INVEST,  , 
    IO, 98, 2022081100,   , BEST,   0, 220N,  714E,  15,  991, DB,   0,    ,    0,    0,    0,    0,    0,    0,   0,   0,   0,   A,   0,    ,   0,   0,     INVEST,  , 
    IO, 98, 2022081106,   , BEST,   0, 222N,  706E,  15,  990, DB,   0,    ,    0,    0,    0,    0,    0,    0,   0,   0,   0,   A,   0,    ,   0,   0,     INVEST,  , 
    IO, 98, 2022081112,   , BEST,   0, 222N,  695E,  20,  990, DB,   0,    ,    0,    0,    0,    0,  992,   80,  55,   0,   0,   A,   0,    ,   0,   0,     INVEST,  , 
    2022-8-12 02:37 回复
  • ygsj24 CMG
    0 引用 3
    IO, 98, 2022081118,   , BEST,   0, 224N,  682E,  25,  990, TD,   0,    ,    0,    0,    0,    0,  992,   80,  55,   0,   0,   A,   0,    ,   0,   0,     INVEST,  , 
    2022-8-12 04:43 回复
  • ygsj24 CMG
    0 引用 4

          (1) AN AREA OF CONVECTION (INVEST 98A) HAS PERSISTED NEAR 22.2N
    69.5E, APPROXIMATELY 385 NM SOUTHEAST OF KARACHI, PAKISTAN. ANIMATED
    MULTISPECTRAL SATELLITE IMAGERY AND AN 111316Z SSMIS 91GHZ IMAGE DEPICT
    FLARING CONVECTION WRAPPING AROUND A WEAKLY DEFINED LOW LEVEL
    CIRCULATION CENTER (LLCC). THERE IS BROAD ELONGATED CIRCULATION OVER
    LAND WITH 15-20 KNOT WINDS. CURRENT SURFACE OBSERVATIONS SHOW THE
    CIRCULATION IS STILL PARTIALLY OVER LAND BUT IS SLOWLY MOVING OUT OVER
    THE GULF OF KUTCH INTO THE ARABIAN SEA. UPPER LEVEL ANALYSIS INDICATES
    98A IS IN A MARGINALLY FAVORABLE ENVIRONMENT FOR DEVELOPMENT WITH LOW TO
    MODERATE (10-20KT) VERTICAL WIND SHEAR (VWS) OFFSET BY GOOD DIVERGENCE
    ALOFT AND WARM (27-28C) SEA SURFACE TEMPERATURES (SST). GLOBAL MODELS
    ARE IN GOOD AGREEMENT THAT 98A WILL CONTINUE NORTH-NORTHWESTWARD AND
    DEVELOP OVER THE ARABIAN SEA WITH GFS AND ECMWF SHOWING DIFFERENT LEVELS
    OF DEVELOPMENT AND DIFFERENT FORECAST TRACKS. MAXIMUM SUSTAINED SURFACE
    WINDS ARE ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
    ESTIMATED TO BE NEAR 990 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
    SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO
    LOW.
    2022-8-12 04:44 回复
  • ygsj24 CMG
    0 引用 5
    IO, 98, 2022081200,   , BEST,   0, 227N,  661E,  25,  992, TD,   0,    ,    0,    0,    0,    0,  993,  175,  55,   0,   0,   A,   0,    ,   0,   0,     INVEST, S, 
    2022-8-12 04:50 回复
  • ygsj24 CMG
    0 引用 6

          (1) THE AREA OF CONVECTION (INVEST 98A) PREVIOUSLY LOCATED NEAR
    22.2N 69.5E IS NOW LOCATED NEAR 22.6N 66.3E, APPROXIMATELY 141 NM
    WEST-SOUTHWEST OF KARACHI, PAKISTAN. AN AREA OF CONVECTION (INVEST
    98A) PREVIOUSLY LOCATED NEAR 22.2N 69.5E IS NOW LOCATED NEAR 22.6N
    66.3E, APPROXIMATELY 141 NM SOUTH-SOUTHWEST OF KARACHI, PAKISTAN. A
    111706Z SCATTEROMETRY PASS SHOWED A FIELD OF 25-30KT WINDS IN THE
    NORTHWESTERN AND WESTERN SECTORS. ANIMATED MULTISPECTRAL SATELLITE
    IMAGERY REVEALS FLARING CONVECTION WRAPPING AROUND A FULLY OBSCURE
    AND CONSOLIDATING LOW LEVEL CIRCULATION CENTER (LLCC). THE CIRCULATION
    IS BECOMING BETTER DEFINED AND CONVECTION IS DEEPENING. CURRENT
    SURFACE OBSERVATIONS SHOW THE MAJORITY OF THE SYSTEM IS MOSTLY INTO
    THE ARABIAN SEA AND CONTINUES TO TRACK NORTHWESTWARD. UPPER LEVEL
    ANALYSIS INDICATES 98A IS IN A FAVORABLE ENVIRONMENT FOR DEVELOPMENT
    WITH LOW (05-10KT) VERTICAL WIND SHEAR (VWS) OFFSET BY GOOD DIVERGENCE
    ALOFT AND WARM (27-28C) SEA SURFACE TEMPERATURES (SST). GLOBAL MODELS
    ARE GRADUALLY MOVING 98A NORTH-NORTHWESTWARD AND DEVELOPING OVER THE
    ARABIAN SEA NEAR PAKISTAN. MAXIMUM SUSTAINED SURFACE WINDS ARE
    ESTIMATED AT 21 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
    TO BE NEAR 990 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
    TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.
    2022-8-12 04:52 回复
  • ygsj24 CMG
    0 引用 7
    IO, 03, 2022081206,   , BEST,   0, 217N,  657E,  35,  991, TS,  34, NEQ,   65,  100,   75,   60,  995,  175,  50,   0,   0,   A,   0,    ,   0,   0,      THREE, S,  0,    ,    0,    0,    0,    0, TRANSITIONED, ioA82022 to io032022, 
    2022-8-12 06:23 回复
  • ygsj24 CMG
    0 引用 8

    WTIO31 PGTW 120900
    MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
    SUBJ/TROPICAL CYCLONE 03A (THREE) WARNING NR 001//
    RMKS/
    1. TROPICAL CYCLONE 03A (THREE) WARNING NR 001
       01 ACTIVE TROPICAL CYCLONE IN NORTHIO
       MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
       WIND RADII VALID OVER OPEN WATER ONLY
        ---
       WARNING POSITION:
       120600Z --- NEAR 21.7N 65.7E
         MOVEMENT PAST SIX HOURS - 270 DEGREES AT 07 KTS
         POSITION ACCURATE TO WITHIN 060 NM
         POSITION BASED ON CENTER LOCATED BY SATELLITE
       PRESENT WIND DISTRIBUTION:
       MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
                                100 NM SOUTHEAST QUADRANT
                                075 NM SOUTHWEST QUADRANT
                                060 NM NORTHWEST QUADRANT
       REPEAT POSIT: 21.7N 65.7E
        ---
       FORECASTS:
       12 HRS, VALID AT:
       121800Z --- 22.1N 65.2E
       MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT
                                070 NM SOUTHEAST QUADRANT
                                110 NM SOUTHWEST QUADRANT
                                030 NM NORTHWEST QUADRANT
       VECTOR TO 24 HR POSIT: 300 DEG/ 03 KTS
        ---
       24 HRS, VALID AT:
       130600Z --- 22.4N 64.6E
       MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
       RADIUS OF 034 KT WINDS - 020 NM NORTHEAST QUADRANT
                                090 NM SOUTHEAST QUADRANT
                                150 NM SOUTHWEST QUADRANT
                                030 NM NORTHWEST QUADRANT
       VECTOR TO 36 HR POSIT: 015 DEG/ 03 KTS
        ---
       36 HRS, VALID AT:
       131800Z --- 23.0N 64.8E
       MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
        ---
    REMARKS:
    120900Z POSITION NEAR 21.8N 65.6E.
    12AUG22. TROPICAL CYCLONE 03A (THREE), LOCATED APPROXIMATELY 199
    NM SOUTH-SOUTHWEST OF KARACHI, PAKISTAN, HAS TRACKED WESTWARD AT
    07 KNOTS OVER THE PAST SIX HOURS.
    MAXIMUM SIGNIFICANT WAVE HEIGHT AT 120600Z IS 16 FEET. NEXT
    WARNINGS AT 121500Z, 122100Z, 130300Z AND 130900Z.
    //
    NNNN
    WDIO31 PGTW 120900
    MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
    SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03A (THREE) WARNING NR
    001//
    RMKS/
    1. FOR METEOROLOGISTS.
    2. 6 HOUR SUMMARY AND ANALYSIS.
    
    SUMMARY:
       INITIAL POSITION: 21.7N 65.7E
       INITIAL INTENSITY: 35 KTS
       GEOGRAPHIC REFERENCE: 199 NM SOUTH-SOUTHWEST OF KARACHI,
    PAKISTAN
       MOVEMENT PAST 6 HOURS: WESTWARD AT 07 KTS
       SIGNIFICANT WAVE HEIGHT: 16 FEET
    
    SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
    ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A SHEARED
    SYSTEM, WITH DEEP FLARING CONVECTION DISPLACED TO THE WEST OF A
    PARTIALLY OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC). TC 03A HAS
    EMERGED OFF THE GUJARAT PENINSULA AND MOVED WESTWARD UNDER A
    MARGINALLY FAVORABLE UPPER-LEVEL FLOW PATTERN, WHICH ALLOWED FOR A
    BRIEF BURST OF CONVECTIVE DEVELOPMENT AND ORGANIZATION. JTWC HAND
    ANALYSIS OF 120000Z UPPER-LEVEL ATMOSPHERIC MOTION VECTORS (AMVS)
    REVEALED A POINT SOURCE OVER TOP OF THE LLCC, WHICH HAS INDUCED
    RELATIVELY LOW SHEAR, IN THE 10-15 KNOT RANGE. SUBSEQUENT AMVS
    REVEAL THIS POINT SOURCE IS MOVING OFF TO THE WEST OF THE LLCC,
    LEAVING IT VULNERABLE TO INCREASING EASTERLY PRESSURE AND SHEAR,
    ALREADY STARTING TO INCREASE. A 120044Z SSMIS 91GHZ MICROWAVE IMAGE
    REVEALS DISORGANIZED DEEP CONVECTION CURVED CYCLONICALLY IN TOWARDS
    THE CENTER, THROUGHOUT THE WESTERN HEMISPHERE OF THE SYSTEM. THE
    INITIAL POSITION IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON AN
    EXTRAPOLATION OF THE MICROWAVE IMAGERY AND THE PGTW FIX POSITION. A
    120620Z ASCAT-B PARTIAL PASS REVEALED 35-40 KNOT WINDS IN THE
    WESTERN HEMISPHERE OF THE CIRCULATION, LENDING INCREASED
    CONFIDENCE TO THE INITIAL INTENSITY, WHICH IS NUDGED HIGHER THAN
    THE AGENCY DVORAK FIXES. THE SYSTEM LIES IN A MARGINAL ENVIRONMENT
    WITH WARM (28-29C) SSTS, MODERATE VWS (20-25 KTS) AND STRONG
    EQUATORWARD OUTFLOW. THE SYSTEM LIES IN A WEAK STEERING
    ENVIRONMENT, CAUGHT IN A COL REGION BETWEEN A RIDGE OVER THE SAUDI
    PENINSULA, A WESTWARD EXTENSION OF THE STR OVER FAR NORTHERN INDIA
    AND A NEAR EQUATORIAL RIDGE (NER) JUST SOUTHWEST OF SOUTHERN INDIA.
    
    INITIAL WIND RADII BASIS: OBJECTIVE BEST TRACK.
    
    CURRENT STEERING MECHANISM: WEAK STEERING PATTERN.
    
    AGENCY DVORAK AND AUTOMATED FIXES:
       PGTW: T1.5 - 25 KTS
       KNES: T1.5 - 25 KTS
       DEMS: T1.5 - 25 KTS
    
    FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
       VWS: 20-25 KTS
       SST: 28-29 CELSIUS
       OUTFLOW: STRONG EQUATORWARD
       OTHER FACTORS: DRY AIR SOUTHEAST AND NORTH OVER SOUTHERN
    PAKISTAN.
    
    ANALYSIS CONFIDENCE:
       INITIAL POSITION: MEDIUM
       INITIAL INTENSITY: MEDIUM
       INITIAL WIND RADII: MEDIUM
    
    3. FORECAST REASONING.
    
    SIGNIFICANT FORECAST CHANGES: THIS INITIAL PROGNOSTIC REASONING
    MESSAGE ESTABLISHES THE FORECAST PHILOSOPHY.
    
    FORECAST DISCUSSION: TC 03A RAPIDLY DEVELOPED AND INTENSIFIED TO A
    TROPICAL STORM STRENGTH AFTER EMERGING OVER WATER. NOW THAT ITS
    MOVED INTO THE NORTH-CENTRAL NORTH ARABIAN SEA, IT HAS MOVED INTO A
    WEAK STEERING PATTERN, TRAPPED BETWEEN COMPETING STEERING
    INFLUENCES OF A SERIES OF DEEP-LAYER RIDGES TO THE WEST, NORTH AND
    SOUTH. OVER THE NEXT 24 TO 36 HOURS, THE WESTERN EXTENSION OF RIDGE
    TO THE NORTH IS EXPECTED TO RECEDE AND WEAKEN, AND THE SOUTHERN
    RIDGE WILL BECOME THE DOMINANT STEERING MECHANISM, WITH THE RIDGE
    OF THE SAUDI PENINSULA ACTING AS A BLOCK TO MUCH FURTHER WESTWARD
    MOVEMENT. AS THE NER TO THE SOUTH MOVES DRIFTS NORTHWARD, IT WILL
    PUSH TC 03A NORTH AS WELL, WITH THE SYSTEM FORECAST TO SLOWLY MOVE
    NORTHWEST THEN NORTH THROUGH THE FORECAST PERIOD. THE BEST
    ENVIRONMENTAL CONDITIONS ARE OCCURRING NOW OR LIKELY ALREADY COME
    AND GONE, AND THUS THE SYSTEM IS LIKELY TO EXPERIENCE ONLY A VERY
    SHORT WINDOW OF OPPORTUNITY FOR FURTHER INTENSIFICATION, WITH A
    PEAK OF 40 KNOTS POSSIBLE BY TAU 12. THEREAFTER, AS THE UPPER-LEVEL
    POINT SOURCE DISSIPATES AND MOVES AWAY, THE GENERALLY STRONG
    EASTERLY FLOW ALOFT ASSOCIATED WITH THE TROPICAL EASTERLY JET (TEJ)
    WILL MOVE IN ONCE MORE, AND SHEAR THE SYSTEM APART. THIS WILL BE
    ACCOMPANIED BY AN INFLUX OF DRY AND DUSTY AIR FROM THE DESERTS OF
    AFGHANISTAN AND PAKISTAN, WHICH WILL SMOTHER ANY REMNANT
    CONVECTION, LEAVING AN EXPOSED AND STEADILY WEAKENING CIRCULATION
    WHICH IS EXPECTED TO DISSIPATE AS A TROPICAL CYCLONE NO LATER THAN
    TAU 36.
    
    MODEL DISCUSSION: DETERMINISTIC TRACK GUIDANCE IS IN GENERAL
    AGREEMENT, AT LEAST THROUGH THE DURATION OF THE FORECAST, WITH ALL
    CONSENSUS MEMBERS AGREEING ON A SLOW WEST-NORTHWESTWARD TRACK
    THROUGH TAU 24, FOLLOWED BY A SHARP TURN TO THE NORTH-NORTHEAST BY
    TAU 36. SPREAD IS ROUGHLY 140NM BETWEEN THE BULK OF THE MODELS, WITH
    GFS ON THE FAR WEST AND ECMWF ON THE FAR EAST SIDE OF THE ENVELOPE.
    NAVGEM MEANWHILE IS DISCOUNTED AS IT TRACKS THE CIRCULATION BACK
    OVER LAND EAST OF KARACHI BY TAU 36, WHICH IS HIGHLY UNREALISTIC.
    THE JTWC FORECAST LIES CLOSE TO THE CONSENSUS MEAN WITH MEDIUM
    CONFIDENCE. INTENSITY GUIDANCE IS ALSO IN FAIRLY GOOD AGREEMENT,
    WITH HWRF, COAMPS-TC AND DECAY-SHIPS (GFS) INDICATING A PEAK OF 40
    KNOTS AT TAU 12 FOLLOWED BY STEADY WEAKENING TO 30 KNOTS BY TAU 36.
    THE JTWC FORECAST LIES ON THE CONSENSUS MEAN THROUGH TAU 12 AND
    DISSIPATES THE SYSTEM AT 30 KNOTS BAY TAU 36, IN LINE WITH THE BULK
    OF THE GUIDANCE, WITH MEDIUM CONFIDENCE.
    
    FORECAST CONFIDENCE:
       TRACK 0 - 72 HR: MEDIUM
       INTENSITY 0 - 72 HR: MEDIUM//
    NNNN
    2022-8-12 06:24 回复
  • ygsj24 CMG
    0 引用 9
    IO, 03, 2022081212,   , BEST,   0, 220N,  656E,  35,  989, TS,  34, NEQ,    0,  100,   75,   60,  994,  150,  50,   0,   0,   A,   0,    ,   0,   0,      THREE, S, 
    2022-8-13 06:11 回复
  • ygsj24 CMG
    0 引用 10

    WTIO31 PGTW 121500
    MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
    SUBJ/TROPICAL CYCLONE 03A (THREE) WARNING NR 002//
    RMKS/
    1. TROPICAL CYCLONE 03A (THREE) WARNING NR 002   
       01 ACTIVE TROPICAL CYCLONE IN NORTHIO
       MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
       WIND RADII VALID OVER OPEN WATER ONLY
        ---
       WARNING POSITION:
       121200Z --- NEAR 22.0N 65.6E
         MOVEMENT PAST SIX HOURS - 345 DEGREES AT 03 KTS
         POSITION ACCURATE TO WITHIN 060 NM
         POSITION BASED ON CENTER LOCATED BY SATELLITE
       PRESENT WIND DISTRIBUTION:
       MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       RADIUS OF 034 KT WINDS - 000 NM NORTHEAST QUADRANT
                                100 NM SOUTHEAST QUADRANT
                                075 NM SOUTHWEST QUADRANT
                                060 NM NORTHWEST QUADRANT
       REPEAT POSIT: 22.0N 65.6E
        ---
       FORECASTS:
       12 HRS, VALID AT:
       130000Z --- 22.3N 65.2E
       MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       RADIUS OF 034 KT WINDS - 000 NM NORTHEAST QUADRANT
                                070 NM SOUTHEAST QUADRANT
                                110 NM SOUTHWEST QUADRANT
                                040 NM NORTHWEST QUADRANT
       VECTOR TO 24 HR POSIT: 315 DEG/ 03 KTS
        ---
       24 HRS, VALID AT:
       131200Z --- 22.7N 64.8E
       MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
       RADIUS OF 034 KT WINDS - 000 NM NORTHEAST QUADRANT
                                090 NM SOUTHEAST QUADRANT
                                130 NM SOUTHWEST QUADRANT
                                050 NM NORTHWEST QUADRANT
       VECTOR TO 36 HR POSIT: 360 DEG/ 03 KTS
        ---
       36 HRS, VALID AT:
       140000Z --- 23.2N 64.8E
       MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
       WIND RADII VALID OVER OPEN WATER ONLY
       DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER
        ---
    REMARKS:
    121500Z POSITION NEAR 22.1N 65.5E.
    12AUG22. TROPICAL CYCLONE 03A (THREE), LOCATED APPROXIMATELY 185
    NM SOUTH-SOUTHWEST OF KARACHI, PAKISTAN, HAS TRACKED NORTH-
    NORTHWESTWARD AT 03 KNOTS OVER THE PAST SIX HOURS.
    MAXIMUM SIGNIFICANT WAVE HEIGHT AT 121200Z IS 14 FEET. NEXT
    WARNINGS AT 122100Z, 130300Z, 130900Z AND 131500Z.
    //
    NNNN
    WDIO31 PGTW 121500
    MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
    SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 03A (THREE) WARNING NR 
    002//
    RMKS/
    1. FOR METEOROLOGISTS.
    2. 6 HOUR SUMMARY AND ANALYSIS.
    
    SUMMARY:
       INITIAL POSITION: 22.0N 65.6E
       INITIAL INTENSITY: 35 KTS
       GEOGRAPHIC REFERENCE: 185 NM SOUTH-SOUTHWEST OF KARACHI,
    PAKISTAN
       MOVEMENT PAST 6 HOURS: NORTH-NORTHWESTWARD AT 03 KTS
       SIGNIFICANT WAVE HEIGHT: 14 FEET
    
    SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
    ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A PARTIALLY
    EXPOSED LOW LEVEL CIRCULATION CENTER (LLCC), UNDER CIRRUS BLOWOFF
    EMANATING FROM DEEP CONVECTIVE ACTIVITY SHEARED TO THE WEST. TC 03A
    HAS PEAKED, WITH THE EARLIER POINT SOURCE ALOFT WHICH HAD ALLOWED
    FOR A MESOSCALE REDUCTION IN THE SHEAR, HAVING DISSIPATED, REPLACED
    BY THE SEASONAL STRONG TROPICAL EASTERLY JET (TEJ) ASSOCIATED FLOW
    PATTERN. A 121200Z F16 SSMIS 91GHZ MICROWAVE IMAGE REVEALED THE
    LLCC, DEVOID OF ANY SIGNIFICANT CONVECTION, AND LENT HIGH
    CONFIDENCE TO THE INITIAL POSITION. THE INITIAL INTENSITY REMAINS
    SET AT 35 KNOTS BASED IN LARGE PART ON THE CIMSS ADT ESTIMATE, ABOVE
    THE SUBJECTIVE DVORAK INTENSITY ESTIMATES. THE ENVIRONMENT HAS
    BECOME EVER MORE HOSTILE, WITH SHEAR DRAMATICALLY INCREASING TO
    ROUGHLY 30 KNOTS, MORE THAN SUFFICIENT TO OFFSET ANY DOWNSTREAM
    DIVERGENCE ALOFT AND THE WARM SSTS, AND THE FIRST HINTS OF A NOSE
    OF MID-LEVEL DRY AIR PUNCHING IN FROM THE EAST. THE SYSTEM LIES IN
    A WEAK STEERING PATTERN AND IS DRIFTING RATHER AIMLESSLY TO THE
    NORTH.
    
    INITIAL WIND RADII BASIS: PERSISTENCE 
    
    CURRENT STEERING MECHANISM: WEAK STEERING PATTERN IN A COL REGION
    BETWEEN A SUBTROPICAL RIDGE (STR) OVER THE SAUDI PENINSULA, AN
    EXTENSION OF THE STR EXTENDING FROM CENTRAL CHINA TO AFGHANISTAN
    AND A NEAR EQUATORIAL RIDGE (NER) CENTERED SOUTHWEST OF SOUTHERN
    INDIA. 
    
    AGENCY DVORAK AND AUTOMATED FIXES: 
       PGTW: T2.0 - 30 KTS
       KNES: T1.5 - 25 KTS
       DEMS: T1.5 - 25 KTS
       CIMSS ADT: 35 KTS AT 121215Z
    
    FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINALLY
    UNFAVORABLE
       VWS: 25-30 KTS
       SST: 28-29 CELSIUS
       OUTFLOW: MODERATE EQUATORWARD
    
    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: TRAPPED BETWEEN A SERIES OF LOW TO MID-LEVEL
    RIDGES DESCRIBED ABOVE, TC 03A WILL EXHIBIT ERRATIC MOVEMENT
    THROUGH THE DURATION OF THE FORECAST. MEAN MOTION IS EXPECTED TO BE
    NORTH-NORTHWESTWARD AS THE RIDGE EXTENSION TO THE NORTH RECEDES AND
    WEAKENS, AND THE NER PUSHES NORTH TO 10N, MOVING TC 03A NORTHWARD
    AS WELL. BUT SIGNIFICANT DEPARTURES FROM THIS FORECAST ARE POSSIBLE
    DUE TO THE LACK OF A STRONG STEERING MECHANISM. NOW THAT THE SYSTEM
    HAS LOST THE PROTECTION OF THE UPPER-LEVEL POINT SOURCE AND IS
    EXPOSED TO THE FULL FORCE OF THE TEJ WINDS ALOFT, IT IS FORECAST TO
    SLOWLY SUCCUMB TO THE INFLUENCE OF MODERATE TO HIGH VWS AND AN
    INFLUX OF MID-LEVEL DRY AIR PUSHING SOUTH OUT OF PAKISTAN. HOWEVER,
    DUE TO THE STRONG LOW-LEVEL SOUTHWESTERLY MONSOONAL FLOW ALONG THE
    SOUTHERN FLANK OF THE SYSTEM FEEDING STRONG VORTICITY INTO THE
    CIRCULATION, IT WILL TAKE SOME TIME FOR THE SYSTEM TO SPIN DOWN
    BELOW GALE FORCE, EXPECTED TO OCCUR NO LATER THAN TAU 36,
    POTENTIALLY AS EARLY AS TAU 24. 
    
    MODEL DISCUSSION: TRACK GUIDANCE IS IN GENERAL AGREEMENT ON A SLOW
    DRIFT TO THE NORTHWEST THROUGH THE FORECAST PERIOD, WITH GFS TAKING
    THE SYSTEM FURTHEST TO THE WEST WHILE THE ECMWF FURTHEST EAST. THE
    JTWC FORECAST CLOSELY TRACKS THE ECMWF WITH LOW CONFIDENCE DUE TO
    THE VAGARIES ASSOCIATED WITH WEAK STEERING PATTERNS. INTENSITY
    GUIDANCE IS IN RELATIVELY GOOD AGREEMENT, WITH ALL BUT THE
    COAMPS-TC INDICATING A NEAR-TERM INTENSIFICATION TO 40 KNOTS
    FOLLOWED BY SLOW BUT STEADY WEAKENING. THE JTWC FORECAST LIES BELOW
    THE GUIDANCE THROUGH TAU 24 AND LIES ALONG THE CONSENSUS MEAN
    THEREAFTER. CONFIDENCE IN THE INTENSITY FORECAST IS MEDIUM. 
    
    FORECAST CONFIDENCE:
       TRACK 0 - 72 HR: LOW
       INTENSITY 0 - 72 HR: MEDIUM//
    NNNN
    2022-8-13 06:13 回复
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