|
|
楼主 |
发表于 2025-6-24 04:48
|
显示全部楼层
JTWC/02W/#06/06-23 18Z Prognostic Reasoning
WDPN31 PGTW 232100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 02W (SEPAT) WARNING NR
006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
SUMMARY:
INITIAL POSITION: 28.4N 141.9E
INITIAL INTENSITY: 35 KTS
GEOGRAPHIC REFERENCE: 218 NM NORTH OF IWO TO
MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 17 KTS
SIGNIFICANT WAVE HEIGHT: 17 FEET
SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS A
COMPACT SYSTEM CHARACTERIZE BY WELL-DEFINED LOW-LEVEL BANDING
FEATURES. DURING THE OVERNIGHT HOURS, A BRIEF PERIOD OF ENHANCED
POLEWARD OUTFLOW, SUPPORTED BY THE TROPICAL UPPER TROPOSPHERIC TROUGH
(TUTT) CELL TO THE SOUTHWEST, ALLOWED THE LOW LEVEL CIRCULATION CENTER
(LLCC) TO ALIGN WITH CONVECTION LEADING TO A BRIEF INTENSIFICATION OF
TS 02W. OVER THE PAST COUPLE OF HOURS, CONVECTION HAS LARGELY
DISSIPATED, REVEALING THE INNER, LOW-LEVEL STRUCTURE. IN THE LAST HOUR
HOWEVER, EIR IMAGERY INDICATES CONVECTION REFORMING IN CLOSE PROXIMITY
TO THE LLCC. A 231552Z AMSR2 COLOR ENHANCED 89GHZ
MICROWAVE IMAGE INDICATED SIGNIFICANT SOUTHERLY SHEAR, WITH THE
UPPER-LEVEL CONVECTION AND VORTEX DISPLACED ABOUT 30NM NORTH OF THE
LOW-LEVEL VORTEX CENTER. EARLIER ASCAT DATA FROM AROUND 1400Z
INDICATED A WELL-DEFINED LLCC, AND 35-40 KNOT SURFACE WINDS
EXTENDING OUTWARD ABOUT 100NM IN THE EASTERN HEMISPHERE OF THE
CIRCULATION, WITH THE MAJORITY OF THE ELEVATED WINDS TO BE FOUND IN
THE NORTHEASTERN SECTOR. THE ENVIRONMENT IS MARGINAL. WHILE SSTS
REMAIN WARM, AND DEEP-LAYER SHEAR REMAINS LOW, THE UPPER-LEVEL
PATTERN IS EVOLVING. THE TUTT MOVING AWAY TO THE SOUTHWEST AND
THE SYSTEM MOVING UNDER A COL-REGION, RESULTING IN REDUCED OUTFLOW
ALOFT AND MODERATE MID-LEVEL SOUTHERLY SHEAR.
INITIAL WIND RADII BASIS: PERSISTENCE WITH EARLIER SCATTEROMETER
DATA.
CURRENT STEERING MECHANISM: SOUTHWESTERN PERIPHERY OF A DEEP-LAYER
SUBTROPICAL RIDGE (STR) CENTERED IN THE NORTHERN PACIFIC.
AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.5 - 35 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.0 - 30 KTS
KNES: T3.0 - 45 KTS
CIMSS SATCON: 44 KTS AT 231500Z
CIMSS ADT: 35 KTS AT 231730Z
CIMSS AIDT: 37 KTS AT 231730Z
CIMSS D-MINT: 31 KTS AT 231554Z
CIMSS D-PRINT: 31 KTS AT 231830Z
FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: MARGINAL
VWS: 5-10 KTS
SST: 27-28 CELSIUS
OUTFLOW: WEAK POLEWARD
ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: HIGH
3. FORECAST REASONING.
SIGNIFICANT FORECAST CHANGES: THE END-PHASE TRANSITION HAS BEEN
CHANGED FROM A DISSIPATION SCENARIO TO AN EXTRATROPICAL TRANSITION
(ETT) SCENARIO.
FORECAST DISCUSSION: TS 02W IS PROJECTED TO CONTINUE TRACKING
TOWARDS THE NORTHWEST OVER THE NEXT 24 HOURS, STEERED BY THE
SOUTHWESTERN PERIPHERY OF THE STEERING RIDGE LOCATED IN THE NORTHERN
PACIFIC. BY TAU 24 THE SYSTEM WILL APPROACH THE RIDGE
AXIS, SLOWING DOWN A COUPLE OF KNOTS BETWEEN TAU 24 AND TAU 36 AS
IT MOVES ACROSS THE RIDGE AXIS. SUBSEQUENTLY, IT WILL ACCELERATE ONCE
AGAIN AS IT TURNS NORTHEASTWARD. THE CENTER OF THE TS 02W IS EXPECTED
TO CLIP THE SOUTHERN AND EASTERN EDGE OF THE BOSO PENINSULA BETWEEN
TAUS 36 AND 48 BEFORE ACCELERATING FURTHER INTO THE OPEN WATERS OFF
EASTERN HONSHU THROUGH THE REMAINDER OF THE FORECAST PERIOD. REGARDING
INTENSITY, WITH THE RENEWED DEVELOPMENT OF DEEP CONVECTION, SLIGHT
INTENSIFICATION IS POSSIBLE OVER THE NEXT FEW HOURS, THOUGH THIS IS
NOT SPECIFICALLY CAPTURED IN THE FORECAST. AS
THE SYSTEM MOVES FURTHER POLEWARD OVER THE NEXT 12 TO 24 HOURS, IT
WILL ENCOUNTER AN INCREASINGLY UNFAVORABLE UPPER-LEVEL ENVIRONMENT.
THE 200MB WINDS WILL SHIFT TO NORTHWESTERLY, INDUCING CONVERGENT FLOW
ALOFT AND DEPRIVING THE SYSTEM OF SIGNIFICANT OUTFLOW ALOFT. AS THE
WEAKENED VORTEX APPROACHES THE JAPANESE COAST, IT WILL MOVE NORTH
OF THE 26C ISOTHERM AND BEGIN THE EARLY PHASE OF EXTRATROPICAL
TRANSITION (ETT) AS IT BEGINS TO INTERACT WITH AN APPROACHING
MID-LATITUDE SYSTEM MOVING EASTWARD ACROSS THE SEA OF JAPAN. AS THE
SYSTEM MAKES ITS CLOSEST APPROACH TO YOKOSUKA, IT WILL HAVE BE A
RELATIVELY SHALLOW SYSTEM, WITH 30KT WINDS CONFINED TO THE
EASTERN HEMISPHERE OF THE SYSTEM. ETT IS EXPECTED TO BE COMPLETED
NO LATER THAN TAU 72 TS 02W PUSHES NORTHEASTWARD INTO THE WESTERN
PACIFIC. TS 02W WILL BE WEAKENING AS IT UNDERGOES ETT, AND IT IS
POSSIBLE THAT IT DISSIPATES BELOW THE 25 KNOT WARNING THRESHOLD
PRIOR TO COMPLETING THE ETT.
MODEL DISCUSSION: DETERMINISTIC AND ENSEMBLE TRACK GUIDANCE SHOW
STRONG AGREEMENT, WITH MINIMAL CROSS- OR ALONG-TRACK SPREAD THROUGH
TAU 48. MODELS BEGIN TO DIVERGE AFTER THE SYSTEM ROUNDS THE
RIDGE AXIS WITH SPREAD INCREASING TO OVER 250NM IN BOTH AXES BY THE
END OF THE FORECAST PERIOD. THE JTWC FORECAST IS POSITIONED TO THE
WEST OF THE MULTI-MODEL CONSENSUS MEAN, CLOSELY ALIGNING TO THE ECMWF
DETERMINISTIC TRACKER FOR THE ENTIRE FORECAST PERIOD. A NOTABLE
EXCEPTION TO THE TIGHT GUIDANCE GROUPING IS THE ECMWF-AIFS MODEL,
WHICH TAKES THE REMNANT VORTEX NORTH TOWARDS MISAWA AFTER TAU 48.
INTENSITY GUIDANCE IS FOR THE MOST PART IN GOOD AGREEMENT AS WELL,
WITH THE EXCEPTION OF THE DECAY-SHIPS (BOTH GFS AND NAVGEM) WHICH
INDICATE NEAR-TERM INTENSIFICATION TO NEAR 50 KNOTS. THE REMAINDER
OF THE GUIDANCE PACKAGE SHOWS A SLOW BUT STEADY WEAKENING THROUGH
THE FORECAST, WITH PERIODS OF STEADY-STATE INTENSITY, PARTICULARLY
OVER THE NEXT 36 HOURS. THE JTWC FORECAST IS SET SLIGHTLY LOWER
THAN THE CONSENSUS MEAN THROUGH THE FORECAST PERIOD.
FORECAST CONFIDENCE:
TRACK 0 - 72 HR: HIGH
INTENSITY 0 - 72 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
×
评分
-
查看全部评分
|
楼主: ygsj24
发表于 2025-6-23 23:00
发表于 2025-6-24 02:46
