最新回复 (38)
-
AXAU01 ADRM 160102 IDD20020 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - NORTHERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 0102 UTC 16/03/2024 Name: Tropical Low Identifier: 09U Data At: 0000 UTC Latitude: 13.8S Longitude: 137.8E Location Accuracy: within 20nm (35 km) Movement Towards: east (094 deg) Speed of Movement: 3 knots (5 km/h) Maximum 10-Minute Wind: 40 knots (75 km/h) Maximum 3-Second Wind Gust: 55 knots (100 km/h) Central Pressure: 992 hPa Radius of 34-knot winds NE quadrant: 100 nm (185 km) Radius of 34-knot winds SE quadrant: Radius of 34-knot winds SW quadrant: Radius of 34-knot winds NW quadrant: 60 nm (110 km) Radius of 48-knot winds NE quadrant: Radius of 48-knot winds SE quadrant: Radius of 48-knot winds SW quadrant: Radius of 48-knot winds NW quadrant: Radius of 64-knot winds: nm ( km) Radius of Maximum Winds: nm ( km) Dvorak Intensity Code: T2.5/2.5/D0.5/12HRS STT:S0.0/06HRS Pressure of outermost isobar: 1004 hPa Radius of outermost closed isobar: 200 nm (370 km) FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure (UTC) : degrees : nm (km): knots(km/h): hPa +06: 16/0600: 14.1S 138.0E: 035 (065): 045 (085): 989 +12: 16/1200: 14.5S 137.8E: 045 (080): 045 (085): 990 +18: 16/1800: 14.8S 137.6E: 050 (095): 050 (095): 986 +24: 17/0000: 15.1S 137.4E: 055 (100): 050 (095): 986 +36: 17/1200: 15.5S 137.2E: 070 (130): 060 (110): 979 +48: 18/0000: 15.8S 137.2E: 090 (165): 070 (130): 970 +60: 18/1200: 16.0S 137.1E: 110 (205): 055 (100): 982 +72: 19/0000: 16.3S 136.5E: 130 (240): 040 (075): 994 +96: 20/0000: 16.6S 134.4E: 145 (270): 020 (035): 1003 +120: 21/0000: 16.6S 131.4E: 205 (380): 020 (035): 1004 REMARKS: Tropical Low 09U is approaching tropical cyclone intensity, with a vigorous low level circulation and convection continuing to develop and wrap around the centre. There is still some evidence of easterly shear operating, with a strong temperature gradient on the eastern side of the central dense overcast, but the low level centre is now located under the convection. Centre location is based on animated satellite imagery, microwave imagery, and radar. Confidence is fair to good. Dvorak analysis: Curved band wrap of 0.4 to 0.5 gives DT 2.5. MET is not yet available with the system having only recently moved over water. FT/CI = 2.5. Objective aids are: ADT 49kt, AiDT 40kt, DPRINT 40kt, DMINT 38kt, MW Sounders 52kt, SATCON 50 kt (all 1-min average). Intensity is analysed at 40 knots, with gales currently restricted to northern quadrants only, which is supported by recent HSCAT scatterometry. Recent motion has been slowly towards the east under the influence of monsoonal flow. Over the next 24 hours, the system is expected to turn to the south and then the south-southwest as mid-level ridging to the east and southwest become the dominant steering influences. This pattern should see the system continue on a south-southwest track, albeit slowly, until it crosses the southwestern Gulf of Carpentaria coast. There is high uncertainty in the timing of this crossing, with guidance ranging from Sunday to Monday. Beyond that, the mid-level ridge to the south is expected to strengthen and steer the system west across inland parts of the Northern Territory through next week. 09U is developing against moderate easterly wind shear, estimated at 15-20 knots from CIMSS upper wind analysis. This is being offset by otherwise favourable conditions; abundant low and mid-level moisture, and high SSTs (30-31C) over the Gulf of Carpentaria. The system is forecast to become a tropical cyclone in the next 6 hours. A southerly track should steer the system away from the monsoonal westerlies into a lighter shear regime over the next 24 hours, and standard development is forecast once it reaches tropical cyclone intensity. This would see it reach category 3 intensity prior to forecast landfall on Monday. However, if the system moves more quickly and hence crosses the coast earlier, it will have less time to develop and the landfall intensity may be lower. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 16/0730 UTC.
Time (ACST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 10 am March 16 tropical low 13.8S 137.8E 35 +6hr 4 pm March 16 1 14.1S 138.0E 65 +12hr 10 pm March 16 1 14.5S 137.8E 80 +18hr 4 am March 17 2 14.8S 137.6E 95 +24hr 10 am March 17 2 15.1S 137.4E 100 +36hr 10 pm March 17 2 15.5S 137.2E 130 +48hr 10 am March 18 3 15.8S 137.2E 165 +60hr 10 pm March 18 2 16.0S 137.1E 205 +72hr 10 am March 19 tropical low 16.3S 136.5E 240 -
WTPS31 PGTW 160300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 19P (NINETEEN) WARNING NR 003// RMKS/ 1. TROPICAL CYCLONE 19P (NINETEEN) WARNING NR 003 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 160000Z --- NEAR 13.9S 137.9E MOVEMENT PAST SIX HOURS - 155 DEGREES AT 04 KTS POSITION ACCURATE TO WITHIN 050 NM POSITION BASED ON CENTER LOCATED BY A COMBINATION OF SATELLITE AND RADAR PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT REPEAT POSIT: 13.9S 137.9E --- FORECASTS: 12 HRS, VALID AT: 161200Z --- 14.4S 138.0E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 200 DEG/ 03 KTS --- 24 HRS, VALID AT: 170000Z --- 15.0S 137.8E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 210 DEG/ 03 KTS --- 36 HRS, VALID AT: 171200Z --- 15.5S 137.5E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 005 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 215 DEG/ 02 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 180000Z --- 15.8S 137.3E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 025 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 245 DEG/ 02 KTS --- 72 HRS, VALID AT: 190000Z --- 16.2S 136.4E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 265 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 200000Z --- 16.4S 134.1E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 160300Z POSITION NEAR 14.0S 137.9E. 16MAR24. TROPICAL CYCLONE 19P (NINETEEN), LOCATED APPROXIMATELY 417 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA, HAS TRACKED SOUTH- SOUTHEASTWARD AT 04 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 160000Z IS 990 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 160000Z IS 18 FEET. NEXT WARNINGS AT 160900Z, 161500Z, 162100Z AND 170300Z. // NNNN
WDPS31 PGTW 160300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 19P (NINETEEN) WARNING NR 003// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 13.9S 137.9E INITIAL INTENSITY: 50 KTS GEOGRAPHIC REFERENCE: 417 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA MOVEMENT PAST 6 HOURS: SOUTH-SOUTHEASTWARD AT 04 KTS SIGNIFICANT WAVE HEIGHT: 18 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TROPICAL CYCLONE (TC) 19S (NINETEEN) CONTINUES TO STEADILY ORGANIZE AND INTENSIFY IN THE GULF OF CARPENTARIA. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS DEEP, PERSISTENT CONVECTION STEADILY ORGANIZING INTO A BETTER DEFINED STRUCTURE, AND OBSCURING THE LOW LEVEL CIRCULATION CENTER (LLCC). A 152202Z SSMIS 91GHZ IMAGE SHOWED A WEAK, NASCENT MICROWAVE EYE-LIKE FEATURE WHICH ALIGNED WITH THE RADAR-DERIVED CENTER OF ROTATION. HOWEVER, ANALYSIS OF THE 36GHZ IMAGE REVEALS A PRONOUNCED VORTEX TILT, INDUCED BY PERSISTENT MID-LEVEL EASTERLY SHEAR. THE INITIAL POSITION WAS ASSESSED WITH MEDIUM CONFIDENCE BASED ON EXTRAPOLATION OF THE LOW EMISSIVITY REGION (LER) IN THE 36GHZ MICROWAVE IMAGE AND THE AGENCY FIX POSITIONS. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON AN AVERAGE OF AGENCY DVORAK INTENSITY ESTIMATES AS WELL AS THE OBJECTIVE ESTIMATES NOTED BELOW. ADDITIONALLY, A HOT OFF THE PRESSES 160027Z ASCAT-B BULLSEYE PASS REVEALED WINDS UP TO 45-50 KNOTS IN THE NORTHERN HEMISPHERE OF THE CIRCULATION, THOUGH WINDS IN THE REMAINDER OF THE CIRCULATION AT 35 KNOTS OR LESS. THE SYSTEM CONTINUES TO STRUGGLE SOMEWHAT AGAINST MODERATE MID-LEVEL EASTERLY SHEAR. ANIMATED WATER VAPOR IMAGERY AND STORM-SCALE ATMOSPHERIC MOTION VECTORS FROM CIMSS CONTINUE TO DEPICT THAT THE PERSISTENT CONVECTION IS GENERATING EASTWARD OUTFLOW WHICH IS PUSHING BACK AGAINST THE SHEAR, BUT THE SYSTEM HAS YET TO TAKE ADVANTAGE OF THE DECREASED MESOSCALE SHEAR VALUES. OTHER THAN THE SHEAR, THE ENVIRONMENT IS FAVORABLE, WTIH VERY WARM SSTS, HIGH OHC AND DECENT POLEWARD OUTFLOW ALOFT. INITIAL WIND RADII BASIS: PERSISTENCE AND ASCAT DATA. CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A MID-LEVEL NEAR EQUATORIAL RIDGE (NER) TO THE EAST-NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.0 - 45 KTS KNES: T3.5 - 55 KTS ADRM: T2.5 - 35 KTS CIMSS SATCON: 51 KTS AT 152203Z CIMSS ADT: 49 KTS AT 152330Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 5-10 KTS SST: 30-31 CELSIUS OUTFLOW: MODERATE POLEWARD ANALYSIS CONFIDENCE: INITIAL POSITION: MEDIUM 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: TC 19S IS FORECAST TO CONTINUE TRACKING EAST-SOUTHEASTWARD THROUGH TAU 12 BEFORE TURNING SOUTH AND EVENTUALLY SOUTHWEST AS THE NER TO THE NORTHEAST STEADILY BUILDS AND EXTENDS TOWARDS THE SOUTHWEST. THE SYSTEM WILL SLOW DOWN AS IT APPROACHES THE COAST AS THE PRIMARY STEERING MECHANISM SHIFTS. AFTER MAKING LANDFALL SHORTLY AFTER TAU 48, THE SYSTEM WILL ACCELERATE ON A WESTWARD TRACK AS IT COMES UNDER THE STEERING INFLUENCE OF A LOW- TO MID-LEVEL SUBTROPICAL RIDGE (STR) LAYING ACROSS CENTRAL AUSTRALIA. IN TERMS OF INTENSITY, THE SYSTEM STILL HAS SOME WORK TO DO TO ORGANIZE A VERTICALLY ALIGNED VORTEX. AS NOTED ABOVE, SIGNS ARE STARTING TO APPEAR THAT THIS IS ALREADY OCCURRING. ASSUMING THE CONVECTION WILL PERSIST FOR ANOTHER 12 HOURS AND CONTINUE TO EXPAND EASTWARD INTO THE FACE OF THE SHEAR, THE SYSTEM SHOULD ACHIEVE AXISYMMETRIZATION AND EMBARK ON A PERIOD OF RAPID INTENSIFICATION. THE FORECAST CALLS FOR RI TO BEGIN IN EARNEST BY TAU 12, WITH THE SYSTEM REACHING A PEAK OF AT LEAST 80 KNOTS BY TAU 36. AN INCREASE OF DRY MID-LEVEL AIR ENTRAINING INTO THE CORE OF THE SYSTEM, ACCOMPANIED BY A REDUCTION IN UPPER-LEVEL OUTFLOW, WILL INHIBIT ADDITIONAL INTENSIFICATION AFTER TAU 36, BUT THE SYSTEM WILL REMAIN A STRONG TC AS IT CROSSES THE SHORE. ONCE THE SYSTEM IS ASHORE, IT WILL RAPIDLY WEAKEN DUE TO TERRAIN EFFECTS AND WILL FULLY DISSIPATE BY TAU 96. MODEL DISCUSSION: NO MAJOR CHANGES ARE OBSERVED THE DETERMINISTIC OR ENSEMBLE TRACK GUIDANCE AS COMPARED TO THE PREVIOUS RUN. ALL CONSENSUS MEMBERS AGREE ON THE OVERALL TRACK SCENARIO, WITH SOME MINOR DIFFERENCES IN THE TIMING AND STRENGTH OF THE TURN TOWARDS THE SOUTHWEST AND IN THE TRACK SPEED AFTER TAU 36. THE TRACK ENVELOPE IS 100NM AT LANDFALL, EXPANDING TO 115NM AT TAU 96, DEFINED BY THE NAVGEM ON THE EAST AND SOUTH, AND THE ECMWF AND GFS ENSEMBLE MEANS ON THE NORTH AND WEST. THE JTWC TRACK FORECAST IS CONSISTENT WITH THE PREVIOUS FORECAST, AND LIES JUST NORTH OF THE CONSENSUS MEAN AND IN LINE WITH THE CONSENSUS IN TERMS OF TRACK SPEED. CONFIDENCE IS MEDIUM DUE TO THE MODEST SPREAD IN THE GUIDANCE MEMBERS AND UNCERTAINTY IN TRACK SPEED. INTENSITY GUIDANCE IS MIXED, WITH THE MESOSCALE MODELS INCLUDING HWRF, HAFS-A, AND COAMPS-TC BASICALLY GIVING UP ON THE SYSTEM AND KEEPING A LID ON INTENSITY, PEAKING OUT BETWEEN 50-65 KNOTS. MEANWHILE THE SHIPS (NAVGEM) RAMPS UP THE PEAK TO 95 KNOTS AT TAU 48, WHILE SEVERAL RAPID INTENSIFICATION (RI) AIDS INCLUDING RIPA, RICN AND FRIA CONTINUE TO TRIGGER. THE JTWC FORECAST LIES WELL ABOVE THE MESOSCALE MODELS AND THE CONSENSUS MEAN, BUT BELOW THE MOST AGGRESSIVE RI AIDS. HOWEVER, IN LIGHT OF THE VERY LARGE SPREAD IN THE GUIDANCE, THE FORECAST IS SET WITH LOW CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: LOW INTENSITY 72-120 HR: LOW// NNNN
最后于 2024-03-16 10:50:00 被ygsj24编辑 ，原因： -
WTPS31 PGTW 160900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 19P (MEGAN) WARNING NR 004// RMKS/ 1. TROPICAL CYCLONE 19P (MEGAN) WARNING NR 004 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 160600Z --- NEAR 14.5S 137.6E MOVEMENT PAST SIX HOURS - 220 DEGREES AT 06 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY A COMBINATION OF SATELLITE AND SYNOPTIC DATA PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT REPEAT POSIT: 14.5S 137.6E --- FORECASTS: 12 HRS, VALID AT: 161800Z --- 15.0S 137.5E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 110 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 200 DEG/ 03 KTS --- 24 HRS, VALID AT: 170600Z --- 15.6S 137.3E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 205 DEG/ 02 KTS --- 36 HRS, VALID AT: 171800Z --- 16.0S 137.1E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 240 DEG/ 02 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 180600Z --- 16.2S 136.7E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 250 DEG/ 03 KTS --- 72 HRS, VALID AT: 190600Z --- 16.6S 135.5E MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND RADIUS OF 034 KT WINDS - 100 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 265 DEG/ 06 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 200600Z --- 16.8S 133.2E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 160900Z POSITION NEAR 14.6S 137.6E. 16MAR24. TROPICAL CYCLONE 19P (MEGAN), LOCATED APPROXIMATELY 409 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA, HAS TRACKED SOUTHWESTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 160600Z IS 987 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 160600Z IS 20 FEET. NEXT WARNINGS AT 161500Z, 162100Z, 170300Z AND 170900Z.// NNNN
WDPS31 PGTW 160900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 19P (MEGAN) WARNING NR 004// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 14.5S 137.6E INITIAL INTENSITY: 50 KTS GEOGRAPHIC REFERENCE: 409 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA MOVEMENT PAST 6 HOURS: SOUTHWESTWARD AT 06 KTS SIGNIFICANT WAVE HEIGHT: 20 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS TROPICAL CYCLONE (TC) 19P (MEGAN) SHOWING DEEP, PERSISTENT CENTRALIZED CONVECTION MOSTLY OBSCURING THE ASSESSED LOW-LEVEL CIRCULATION CENTER (LLCC). TRANSVERSE BANDS ARE OBSERVED ALONG THE NORTHERN PERIPHERY OF THE CIRCULATION WITH CIRRUS FILAMENTS FLOWING EQUATORWARD ALOFT. SPIRAL BANDS OF DEEP CONVECTION FILL OUT THE WESTERN SEMICIRCLE AND SHALLOW BANDING IS OBSERVABLE THROUGHOUT THE EASTERN SEMICIRCLE WRAPPING INTO THE LLCC. THE INITIAL POSITION IS PLACED WITH MEDIUM CONFIDENCE BASED ON SURFACE OBSERVATIONS AND A 160600Z HIMAWARI-9 VISIBLE SATELLITE IMAGE. THE INITIAL INTENSITY OF 50 KTS IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON SURFACE OBSERVATIONS, PERSISTENCE OF A 160022Z METOP-B SCATTEROMETRY IMAGE, AND THE SUBJECTIVE AND OBJECTIVE INTENSITY ESTIMATES LISTED BELOW. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A MID-LEVEL NEAR EQUATORIAL RIDGE (NER) TO THE EAST-NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.0 - 45 KTS KNES: T3.5 - 55 KTS CIMSS SATCON: 51 KTS AT 160437Z CIMSS ADT: 55 KTS AT 160530Z CIMSS AIDT: 44 KTS AT 160730Z CIMSS DPRINT: 44 KTS AT 160600Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 5-10 KTS SST: 30-31 CELSIUS OUTFLOW: MODERATE EQUATORWARD ANALYSIS CONFIDENCE: INITIAL POSITION: MEDIUM INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 19P (MEGAN) IS FORECAST TO TRACK SOUTHWARD (TAU 00 TO TAU 12) TO SOUTH-SOUTHWESTWARD (TAU 12 TO TAU 36) FOLLOWING THE STEERING INFLUENCE OF AN EXTENSION OF A NEAR-EQUATORIAL RIDGE TO THE EAST-NORTHEAST. ALONG-TRACK, A FAVORABLE ENVIRONMENT HAVING LOW (5-10 KTS) VERTICAL WIND SHEAR (VWS), VERY WARM (30-31 C) SEA SURFACE TEMPERATURES, A MOIST MID LEVEL (RELATIVE HUMIDITY NEAR 70 PCT), OFFSET BY LOW TO MODERATE DIVERGENCE ALOFT. OUTFLOW CONDITIONS ALOFT ARE FORECAST TO BECOME WEAKER FROM TAU 00 TO TAU 36, WHICH IS THE MAJOR RESTRAINT ON THE SYSTEM OVER THIS INTERVAL. HOWEVER, WITH ALL OTHER ENVIRONMENTAL FACTORS ASSESSED AS FAVORABLE, THE SYSTEM IS EXPECTED TO INTENSIFY TO NEAR 70 KTS BY TAU 24, WITH A PEAK INTENSITY LIKELY TO BE OBSERVED BETWEEN TAU 24 AND TAU 36. LANDFALL IS ANTICIPATED TO OCCUR BETWEEN TAU 36 AND TAU 48 ALONG THE SOUTHERN COAST OF THE GULF OF CARPENTARIA. DISSIPATION IS ANTICIPATED TO OCCUR PRIOR TO TAU 96 AS THE SYSTEM MOVES INLAND OVER NORTHERN AUSTRALIA. MODEL DISCUSSION: GLOBAL NUMERICAL MODEL GUIDANCE IS IN OVERALL GOOD AGREEMENT REGARDING TRACK, WITH ALL JTWC CONSENSUS MEMBERS SUGGESTING A SOUTHWARD COMPONENT FROM TAU 00 TO TAU 48. AT TAU 48, ALL MEMBERS THEN TRACK THE SYSTEM WEST-SOUTHWESTWARD TO WESTWARD THROUGH TAU 96. A CROSS-TRACK SPREAD OF 96NM IS PRESENT BETWEEN THE ECMWF ENSEMBLE MEAN AND GALWEM BY TAU 48, LEAVING SOME UNCERTAINTY AS TO WHERE ALONG THE SOUTHERN GULF OF CARPENTARIA THE SYSTEM WILL TRACK ASHORE. INTENSITY GUIDANCE INCLUDES INDICATION THAT RAPID INTENSIFICATION MAY BE OBSERVED IN THE NEXT 24 HOURS. THOUGH, THE PROBABILITY OF OCCURRENCE ASSOCIATED WITH THESE AIDS IS NEAR 30 TO 40 PERCENT. INTENSITY CONSENSUS MEMBERS ARE UNIFORM IN NATURE, INDICATING A RISE IN INTENSITY TO A PEAK PRIOR TO TAU 36, FOLLOWED BY A WEAKENING TREND AS THE SYSTEM TRACKS SOUTH OVER LAND. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM TRACK 72 - 96 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72 - 96 HR: MEDIUM// NNNN
最后于 2024-03-17 08:40:00 被ygsj24编辑 ，原因： -
全球热带气旋监测公报
澳大利亚附近海域热带气旋“梅甘”生成
时 间：16日14时（北京时）
海 域：澳大利亚附近海域
命 名：“梅甘”，MEGAN
中心位置：南纬14.5度、东经137.6度
强度等级：二级热带气旋
最大风力：10级（25米/秒，相当于我国的强热带风暴级）
中心气压：985百帕
参考位置：澳大利亚北部地区达尔文东偏南方向约760公里的海面上
变化过程：过去24小时，“梅甘”由8级加强到10级
预报结论：“梅甘”将原地少动或缓慢向南偏西方向移动，强度逐渐加强。
图1 卫星可见光监测图像（北京时间2024年03月16日14时00分）
最后于 2024-03-16 20:00:00 被ygsj24编辑 ，原因： -
AXAU01 ADRM 161316 IDD20020 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - NORTHERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 1316 UTC 16/03/2024 Name: Tropical Cyclone Megan Identifier: 09U Data At: 1200 UTC Latitude: 14.3S Longitude: 137.7E Location Accuracy: within 15nm (30 km) Movement Towards: south southwest (206 deg) Speed of Movement: 2 knots (4 km/h) Maximum 10-Minute Wind: 50 knots (95 km/h) Maximum 3-Second Wind Gust: 70 knots (130 km/h) Central Pressure: 983 hPa Radius of 34-knot winds NE quadrant: 90 nm (165 km) Radius of 34-knot winds SE quadrant: 60 nm (110 km) Radius of 34-knot winds SW quadrant: 60 nm (110 km) Radius of 34-knot winds NW quadrant: 80 nm (150 km) Radius of 48-knot winds NE quadrant: 50 nm (95 km) Radius of 48-knot winds SE quadrant: Radius of 48-knot winds SW quadrant: Radius of 48-knot winds NW quadrant: 50 nm (95 km) Radius of 64-knot winds: nm ( km) Radius of Maximum Winds: 25 nm (45 km) Dvorak Intensity Code: T3.5/3.5/D1.5/24HRS STT:D0.5/06HRS Pressure of outermost isobar: 1002 hPa Radius of outermost closed isobar: 180 nm (335 km) FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure (UTC) : degrees : nm (km): knots(km/h): hPa +06: 16/1800: 14.5S 137.5E: 035 (065): 055 (100): 980 +12: 17/0000: 14.7S 137.4E: 045 (085): 060 (110): 977 +18: 17/0600: 15.0S 137.3E: 050 (095): 060 (110): 977 +24: 17/1200: 15.2S 137.3E: 060 (110): 065 (120): 975 +36: 18/0000: 15.4S 137.2E: 075 (135): 075 (140): 966 +48: 18/1200: 15.6S 136.9E: 095 (180): 075 (140): 966 +60: 19/0000: 16.0S 136.3E: 115 (215): 045 (085): 989 +72: 19/1200: 16.2S 135.4E: 130 (240): 030 (055): 998 +96: 20/1200: 16.1S 132.7E: 145 (265): 020 (035): 1002 +120: 21/1200: 15.8S 130.1E: 170 (320): 020 (035): 1001 REMARKS: Tropical Cyclone Megan has continued to intensify during the evening, reaching category 2 at 1200 UTC east of Groote Eylandt. The LLCC is evident on Gove radar with tightly wrapped inner band curvature providing a good position fix under a large circular cold cloud cover. Recent microwave imagery indicates strongest convection in the northern semicircle and a weak eye feature. Dvorak analysis: DT was not clear as curved band and embedded centre patterns are not applicable. MET and PAT = 3.5 based on a 24h D+ development trend. FT = CI = 3.5. Objective aids are: ADT 57kt, AiDT 45kt, DPRINT 51kt and MW Sounders 60kt (all 1-min average). Intensity is analysed at 50 knots based on Dvorak and objective aids. Tropical Cyclone Megan is moving slowly south, as mid-level ridging to the east eclipsed monsoon flow to the north as the dominant steering influence. This pattern should see the system continue on a south-southwest track, albeit slowly, until it crosses the southwestern Gulf of Carpentaria coast. There is uncertainty in the timing of this crossing, with guidance ranging from Sunday evening to early Tuesday. Beyond that, the mid-level ridge to the south is expected to strengthen and steer the system west across inland parts of the Northern Territory through next week. Tropical Cyclone Megan has developed against moderate but decreasing easterly wind shear, currently estimated at around 15 knots from CIMSS upper wind analysis. This was offset by otherwise favourable conditions; abundant low and mid-level moisture, and high SSTs (30-31C) over the Gulf of Carpentaria and good upper outflow in eastern and northern quadrants. A southerly track should steer the system further away from the monsoonal westerlies into a light shear regime over the next 24 hours, and a standard rate of development is forecast. This would see Megan reach at least category 3 intensity prior to forecast landfall on Monday. However this comes with uncertainty. On one hand, a period of rapid intensification cannot be ruled out given the favourable atmospheric conditions along the forecast track. Another scenario, however, is the system moving more quickly and hence moving closer to land earlier, in which case it will have less time to develop and the landfall intensity may be lower. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 16/1930 UTC.
Time (ACST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 10 pm March 16 2 14.3S 137.7E 30 +6hr 4 am March 17 2 14.5S 137.5E 65 +12hr 10 am March 17 2 14.7S 137.4E 85 +18hr 4 pm March 17 2 15.0S 137.3E 95 +24hr 10 pm March 17 3 15.2S 137.3E 105 +36hr 10 am March 18 3 15.4S 137.2E 135 +48hr 10 pm March 18 3 15.6S 136.9E 180 +60hr 10 am March 19 1 16.0S 136.3E 215 +72hr 10 pm March 19 tropical low 16.2S 135.4E 240 -
-
AXAU01 ADRM 161923 IDD20020 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - NORTHERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 1922 UTC 16/03/2024 Name: Tropical Cyclone Megan Identifier: 09U Data At: 1800 UTC Latitude: 14.3S Longitude: 137.5E Location Accuracy: within 15nm (30 km) Movement Towards: west southwest (248 deg) Speed of Movement: 1 knots (2 km/h) Maximum 10-Minute Wind: 55 knots (100 km/h) Maximum 3-Second Wind Gust: 75 knots (140 km/h) Central Pressure: 981 hPa Radius of 34-knot winds NE quadrant: 90 nm (165 km) Radius of 34-knot winds SE quadrant: 60 nm (110 km) Radius of 34-knot winds SW quadrant: 60 nm (110 km) Radius of 34-knot winds NW quadrant: 80 nm (150 km) Radius of 48-knot winds NE quadrant: 50 nm (95 km) Radius of 48-knot winds SE quadrant: 30 nm (55 km) Radius of 48-knot winds SW quadrant: 30 nm (55 km) Radius of 48-knot winds NW quadrant: 50 nm (95 km) Radius of 64-knot winds: nm ( km) Radius of Maximum Winds: 15 nm (30 km) Dvorak Intensity Code: T4.0/4.0/D1.5/24HRS STT:D0.5/06HRS Pressure of outermost isobar: 1002 hPa Radius of outermost closed isobar: 180 nm (335 km) FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure (UTC) : degrees : nm (km): knots(km/h): hPa +06: 17/0000: 14.5S 137.4E: 030 (060): 060 (110): 977 +12: 17/0600: 14.8S 137.3E: 045 (080): 060 (110): 977 +18: 17/1200: 15.1S 137.2E: 050 (095): 065 (120): 973 +24: 17/1800: 15.3S 137.2E: 060 (110): 070 (130): 969 +36: 18/0600: 15.6S 137.1E: 080 (145): 075 (140): 964 +48: 18/1800: 15.8S 136.7E: 105 (190): 065 (120): 973 +60: 19/0600: 16.1S 136.0E: 120 (220): 035 (065): 994 +72: 19/1800: 16.3S 134.8E: 130 (235): 030 (055): 997 +96: 20/1800: 16.0S 132.0E: 150 (280): 020 (035): 1002 +120: 21/1800: 15.8S 129.6E: 185 (340): 020 (035): 1001 REMARKS: Tropical Cyclone Megan continues to intensify over the Gulf of Carpentaria, to the east of Groote Eylandt. The LLCC is evident on Gove radar with tightly wrapped inner band curvature providing a good position fix under a large circular cold cloud cover. Recent microwave imagery indicates strongest convection in the northern semicircle and a weak eye feature. Dvorak analysis: DT was not clear as curved band and embedded centre patterns are not applicable. MET and PAT = 4.0 based on a 24h D+ development trend. FT = CI = 4.0. Objective aids are: ADT 74kt, AiDT 70kt, DPRINT 56kt, DMINT 58kt, SATCON 64kt and MW Sounders 60kt (all 1-min average). Intensity is analysed at 55 knots based on Dvorak and objective aids. Tropical Cyclone Megan is drifting slowly south, as mid-level ridging to the east eclipsed monsoon flow to the north as the dominant steering influence. This pattern should see the system continue on a south-southwest track, albeit slowly, until it crosses the southwestern Gulf of Carpentaria coast. There is uncertainty in the timing of this crossing, with guidance ranging from Sunday evening to early Tuesday. Beyond that, the mid-level ridge to the south is expected to strengthen and steer the system west across inland parts of the Northern Territory through next week. Tropical Cyclone Megan has developed against moderate but decreasing easterly wind shear, currently estimated at around 15 knots from CIMSS upper wind analysis. This was offset by otherwise favourable conditions; abundant low and mid-level moisture, and high SSTs (30-31C) over the Gulf of Carpentaria and good upper outflow in eastern and northern quadrants. A southerly track should steer the system further away from the monsoonal westerlies into a light shear regime over the next 24 hours, and a standard rate of development is forecast. This would see Megan reach at least category 3 intensity prior to forecast landfall on Monday. However this comes with uncertainty. On one hand, a period of rapid intensification cannot be ruled out given the favourable atmospheric conditions along the forecast track. Another scenario, however, is the system moving more quickly and hence moving closer to land earlier, in which case it will have less time to develop and the landfall intensity may be lower. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 17/0130 UTC.
Time (ACST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 4 am March 17 2 14.3S 137.5E 30 +6hr 10 am March 17 2 14.5S 137.4E 60 +12hr 4 pm March 17 2 14.8S 137.3E 80 +18hr 10 pm March 17 3 15.1S 137.2E 95 +24hr 4 am March 18 3 15.3S 137.2E 110 +36hr 4 pm March 18 3 15.6S 137.1E 145 +48hr 4 am March 19 3 15.8S 136.7E 190 +60hr 4 pm March 19 tropical low 16.1S 136.0E 220 +72hr 4 am March 20 tropical low 16.3S 134.8E 235 -
WTPS31 PGTW 162100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 19P (MEGAN) WARNING NR 006// RMKS/ 1. TROPICAL CYCLONE 19P (MEGAN) WARNING NR 006 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 161800Z --- NEAR 14.4S 137.5E MOVEMENT PAST SIX HOURS - 270 DEGREES AT 01 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON EYE FIXED BY A COMBINATION OF SATELLITE AND RADAR PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 14.4S 137.5E --- FORECASTS: 12 HRS, VALID AT: 170600Z --- 14.6S 137.5E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 205 DEG/ 02 KTS --- 24 HRS, VALID AT: 171800Z --- 15.0S 137.3E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 225 DEG/ 03 KTS --- 36 HRS, VALID AT: 180600Z --- 15.5S 136.8E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 240 DEG/ 03 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 181800Z --- 15.8S 136.2E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 255 DEG/ 04 KTS --- 72 HRS, VALID AT: 191800Z --- 16.2S 134.5E MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND VECTOR TO 96 HR POSIT: 270 DEG/ 08 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 201800Z --- 16.2S 131.2E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 162100Z POSITION NEAR 14.5S 137.5E. 16MAR24. TROPICAL CYCLONE 19P (MEGAN), LOCATED APPROXIMATELY 402 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA, HAS TRACKED WESTWARD AT 01 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 161800Z IS 980 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 161800Z IS 21 FEET. NEXT WARNINGS AT 170300Z, 170900Z, 171500Z AND 172100Z. // NNNN
WDPS31 PGTW 162100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 19P (MEGAN) WARNING NR 006// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 14.4S 137.5E INITIAL INTENSITY: 65 KTS GEOGRAPHIC REFERENCE: 402 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA MOVEMENT PAST 6 HOURS: WESTWARD AT 01 KTS SIGNIFICANT WAVE HEIGHT: 21 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TROPICAL CYCLONE (TC) 19P (MEGAN) HAS RAPIDLY INTENSIFIED OVER THE PAST 24 HOURS OVER THE WESTERN PORTION OF THE GULF OF CARPENTARIA. ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS AN OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC) HIDING UNDER AN EXPANSIVE CENTRAL DENSE OVERCAST (CDO), WITH OVERSHOOTING TOPS POPPING NEAR THE ASSESSED LLCC POSITION. A VERY TIMELY 161605Z AMSR2 PASS REVEALED A WELL-DEFINED MICROWAVE EYE FEATURE IN BOTH THE 37GHZ AND 89GHZ BANDS. ANALYSIS OF BOTH BANDS REVEALS THAT THE EYE IS NEARLY VERTICALLY STACKED AT THIS POINT, WITH ONLY A MINIMAL AMOUNT OF WESTERLY TILT WITH HEIGHT. THIS INDICATES THAT THE SYSTEM HAS AXISYMMETRIZED OVER THE PAST 12-24 HOURS. ADDITIONALLY THE COLOR ENHANCED 37GHZ IMAGE REVEALS A SOLID CYAN RING FEATURE, AN INDICATOR OF POSSIBLE RAPID INTENSIFICATION (RI) IN THE NEAR-TERM. OVER THE PAST 12 HOURS, RADAR DATA HAS SUGGESTED THE LLCC HAS BECOME NEARLY QUASI-STATIONARY OR IS EVEN DRIFTING BACK EAST-NORTHEASTWARD, THOUGH BEING ON THE EDGE OF THE RADAR COVERAGE OF BOTH THE GOVE AIRPORT AND MORNINGTON ISLAND RADARS, CONFIDENCE IN THE RADAR DATA IS RATHER LOW. BASED STRICTLY ON THE ABOVE MENTIONED MICROWAVE DATA AND ANALYSIS OF THE OVERALL TRENDS IN STORM MOTION, THE INITIAL POSITION WAS ASSESSED WITH HIGH CONFIDENCE. THE INITIAL INTENSITY WAS ASSESSED WITH MEDIUM CONFIDENCE, IN LINE WITH THE KNES AND ADRM DVORAK INTENSITY ESTIMATES, THE SATELLITE CONSENSUS AND THE DPRINT, BUT BELOW THE ADT AND AIDT ESTIMATES WHICH HAVE JUMPED SIGNIFICANTLY HIGHER OVER THE PAST COUPLE OF HOURS. ANALYSIS OF ANIMATED WATER VAPOR IMAGERY AND CIMSS TC-SCALE ATMOSPHERIC MOTION VECTORS SHOWS THAT WHILE THE DEEP LAYER SHEAR REMAINS IN THE MODERATE RANGE (15-20 KTS), THE PERSISTENT CONVECTIVE ACTIVITY HAS SUCCESSFULLY PUSHED BACK AGAINST THE SHEAR, WITH OUTFLOW FILAMENTS EXTENDING WELL TO THE EAST AS WELL AS NOW EXPANDING BOTH EQUATORWARD AND TO A LESSER EXTENT POLEWARD. SSTS ARE VERY WARM AND OHC IS HIGH, PROVIDING AMPLE ENERGY FOR FURTHER INTENSIFICATION. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF AN EXTENSION OF THE NEAR EQUATORIAL RIDGE (NER) CENTERED TO THE NORTHEAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T3.5 - 55 KTS KNES: T4.0 - 65 KTS ADRM: T4.0 - 65 KTS CIMSS SATCON: 64 KTS AT 161546Z CIMSS ADT: 74 KTS AT 161730Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 15-20 KTS SST: 30-31 CELSIUS OUTFLOW: MODERATE POLEWARD AND EQUATORWARD ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: MEDIUM INITIAL WIND RADII: MEDIUM 3. FORECAST REASONING. SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO THE FORECAST FROM THE PREVIOUS WARNING. FORECAST DISCUSSION: TC 19P HAS SLOWED SIGNIFICANTLY OVER THE PAST SIX HOURS OR SO AS THE NER TO THE NORTHEAST HAS WEAKENED SLIGHTLY, RELAXING THE STEERING GRADIENT. OVER THE NEXT 12 HOURS, THE NER IS FORECAST TO BUILD ONCE MORE, WHICH WILL STRENGTHEN THE STEERING INFLUENCE, AND PUSH TC 19P BACK ON A SOUTHWESTWARD TRACK TOWARDS THE COAST NEAR CENTRE ISLAND. TRACK SPEEDS ARE EXPECTED TO REMAIN FAIRLY SLOW, ONLY INCREASING TO ABOUT THREE KNOTS BY TAU 36. LANDFALL IS CURRENTLY EXPECTED JUST WEST OF CENTRE ISLAND AROUND TAU 40. AFTER MOVING INLAND AND WEAKENING, THE SYSTEM WILL COME UNDER THE STEERING INFLUENCE OF A BUILDING SUBTROPICAL RIDGE (STR) OVER SOUTHERN AUSTRALIA AND RACE OFF TO THE WEST THROUGH THE END OF THE FORECAST PERIOD. IN TERMS OF INTENSITY, THE SYSTEM HAS CLEARLY BEEN SUCCESSFUL IN PUSHING BACK AGAINST THE MODERATE EASTERLY SHEAR, GENERATING A MESOSCALE LOW-SHEAR ENVIRONMENT WHICH HAS ALLOWED FOR RAPID AXISYMMETRIZATION. THE LATEST MICROWAVE IMAGERY SUGGESTS THIS PROCESS HAS COMPLETED AND THE PRESENCE OF A CYAN RING INDICATES THAT RI IS LIKELY IN THE OFFING IN THE NEAR-TERM. OUTFLOW ALOFT IS NOT GREAT BUT GOOD ENOUGH, WHILE SSTS AND OHC VALUES ARE VERY SUPPORTIVE, HENCE THE FORECAST CALLS FOR THE SYSTEM TO UNDERGO RI OVER THE NEXT 24 HOURS, REACHING A PEAK OF 90 KNOTS. BY TAU 36, SHEAR IS EXPECTED TO INCREASE SHARPLY AS NORTHEASTERLY CONVERGENT FLOW ALOFT IS ANTICIPATED TO PUSH DOWN ON THE SYSTEM. HOWEVER, THE SYSTEM IS FORECAST TO MAINTAIN INTENSITY THROUGH LANDFALL AS THE SHEAR WILL NOT HAVE ENOUGH TIME TO SIGNIFICANTLY WEAKEN THE SYSTEM BEFORE IT MOVES INLAND. AFTER LANDFALL THE SYSTEM WILL RAPIDLY WEAKEN AND DISSIPATE OVER NORTH-CENTRAL AUSTRALIA NO LATER THAN TAU 72. MODEL DISCUSSION: DETERMINISTIC TRACK GUIDANCE DID NOT PICK UP ON THE ERRATIC MOTION SEEN OVER THE PAST 6 TO 12 HOURS AND FOR THE MOST PART, THE BULK OF THE GUIDANCE CONTINUES TO SHOW AN ACCELERATING TRACK TOWARDS THE COASTLINE. GFS IS THE FASTEST OF THE CONSENSUS MODELS, INDICATING LANDFALL BY TAU 24, CLOSELY FOLLOWED BY THE HAFS-A, HWRF AND COAMPS-TC. THE ECMWF HAS THE LLCC OVER LAND BY TAU 36 WHILE THE REMAINDER OF THE TRACK GUIDANCE DOES NOT SHOW LANDFALL UNTIL TAU 60. CROSS-TRACK SPREAD AT TAU 48 IS 150NM BETWEEN THE FAR OUTLIERS, NAVGEM AND GALWEM. DISCOUNTING THESE, THE REMAINDER OF THE GUIDANCE IS CONFINED TO A 40NM WIDE ENVELOPE. HOWEVER, THE FACT THAT THE MODELS HAVE NOT PICKED UP ON THE ERRATIC MOTION OVER THE PAST FEW HOURS SUGGESTS THAT THEY ARE TAKING THE SYSTEM TOO QUICKLY TO THE COAST. THE JTWC FORECAST LIES JUST NORTH OF THE CONSENSUS MEAN AT ROUGHLY THE SAME SPEED, BUT CONFIDENCE IS MEDIUM DUE TO THE UNCERTAINTY IN THE NEAR-TERM TRACK SPEED. IN THE EXTENDED FORECAST, CONFIDENCE REMAINS MEDIUM ONLY DUE TO THE SHORT-TERM FORECAST CONFIDENCE, AS ALL OF THE GUIDANCE INDICATES AN ACCELERATING TRACK TOWARDS THE WEST AFTER LANDFALL. INTENSITY GUIDANCE REMAINS SOMEWHAT MIXED WITH THE MESOSCALE MODELS (HWRF, HAFS-A, COAMPS-TC) ALL SHOWING LITTLE TO NO INTENSIFICATION PRIOR TO LANDFALL, WHILE THE SHIPS GUIDANCE ALONG WITH SEVERAL RI AIDS INCLUDING RIPA, RICN, FRIA, CHR4 AND RI35 ALL INDICATE STRONG INTENSIFICATION. PEAK INTENSITIES RANGE BETWEEN 65 AND 115 KNOTS. THE JTWC FORECAST ROUGHLY CONFORMS WITH THE RI25 AND SHIPS-GFS GUIDANCE WITH MEDIUM CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN
最后于 2024-03-17 12:00:01 被ygsj24编辑 ，原因： -
AXAU01 ADRM 170104 IDD20020 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - NORTHERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 0104 UTC 17/03/2024 Name: Tropical Cyclone Megan Identifier: 09U Data At: 0000 UTC Latitude: 14.8S Longitude: 137.4E Location Accuracy: within 10nm (20 km) Movement Towards: south southwest (201 deg) Speed of Movement: 3 knots (5 km/h) Maximum 10-Minute Wind: 60 knots (110 km/h) Maximum 3-Second Wind Gust: 85 knots (155 km/h) Central Pressure: 978 hPa Radius of 34-knot winds NE quadrant: 90 nm (165 km) Radius of 34-knot winds SE quadrant: 60 nm (110 km) Radius of 34-knot winds SW quadrant: 60 nm (110 km) Radius of 34-knot winds NW quadrant: 80 nm (150 km) Radius of 48-knot winds NE quadrant: 50 nm (95 km) Radius of 48-knot winds SE quadrant: 30 nm (55 km) Radius of 48-knot winds SW quadrant: 30 nm (55 km) Radius of 48-knot winds NW quadrant: 40 nm (75 km) Radius of 64-knot winds: nm ( km) Radius of Maximum Winds: 20 nm (35 km) Dvorak Intensity Code: T4.0/4.0/D1.5/24HRS STT:S0.0/06HRS Pressure of outermost isobar: 1002 hPa Radius of outermost closed isobar: 180 nm (335 km) FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure (UTC) : degrees : nm (km): knots(km/h): hPa +06: 17/0600: 15.1S 137.4E: 030 (055): 065 (120): 973 +12: 17/1200: 15.3S 137.3E: 040 (075): 070 (130): 969 +18: 17/1800: 15.5S 137.2E: 050 (095): 075 (140): 965 +24: 18/0000: 15.7S 137.1E: 060 (115): 080 (150): 960 +36: 18/1200: 15.9S 136.8E: 080 (145): 075 (140): 965 +48: 19/0000: 16.3S 136.2E: 100 (185): 040 (075): 991 +60: 19/1200: 16.5S 135.2E: 115 (210): 030 (055): 996 +72: 20/0000: 16.5S 133.8E: 120 (225): 025 (045): 998 +96: 21/0000: 16.1S 130.7E: 150 (280): 020 (035): 1000 +120: 22/0000: 16.0S 128.1E: 195 (360): 020 (035): 1002 REMARKS: Tropical Cyclone Megan continues to intensify over the Gulf of Carpentaria, to the southeast of Groote Eylandt. Convection remains vigorous and closely associated with the system centre. Satellite microwave imagery depicts a partial eyewall wrapped mostly around the centre. Confidence in the centre position is good based on satellite imagery plus Gove and Mornington Island radars. Dvorak analysis: DT based on a combination of visible CDO with a 110 nmi diameter, and a curved band of 0.8 wrap with 0.5 added to the T number for a white or colder band. Both patterns yield DT 4.0. MET is 4.0 based on a 24 hour D+ trend with no PT adjustment. FT = CI = 4.0. Objective aids are: ADT 79kt, AiDT 80kt, DPRINT 67kt, DMINT 58kt, SATCON 78kt and MW Sounders 65kt (all 1-min average). Intensity is analysed at 60 knots based on subjective Dvorak, objective aids, and model guidance. Tropical Cyclone Megan is drifting slowly south, with mid-level ridging to the east as the dominant steering influence. This should see the system continue on a slow south-southwest track, albeit slowly, until it crosses the southwestern Gulf of Carpentaria coast. There is uncertainty in the timing of this crossing, with guidance ranging from Sunday evening to early Tuesday morning. Beyond that, the mid-level ridge to the south is expected to strengthen and steer the system west across inland parts of the Northern Territory as a tropical low through next week. Tropical Cyclone Megan has developed against moderate easterly wind shear, currently estimated at around 15-20 knots from CIMSS upper wind analysis. This has been offset by otherwise favourable conditions; abundant low and mid-level moisture, and high SSTs (30-31C) over the Gulf of Carpentaria, plus good upper outflow in the southeastern and northern quadrants. A southerly track should move the system further into the lighter shear regime over the next 24 hours, and a standard rate of development is therefore expected to continue. This would see Megan reach at least high category 3 intensity prior to forecast landfall on Monday. However this comes with uncertainty. On one hand, a period of rapid intensification cannot be ruled out given the favourable atmospheric conditions along the forecast track. Another scenario, however, is the system moving more quickly and hence moving closer to land earlier, in which case it will have less time to develop and the landfall intensity may be lower. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 17/0730 UTC.
Time (ACST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 10 am March 17 2 14.8S 137.4E 20 +6hr 4 pm March 17 3 15.1S 137.4E 55 +12hr 10 pm March 17 3 15.3S 137.3E 75 +18hr 4 am March 18 3 15.5S 137.2E 95 +24hr 10 am March 18 3 15.7S 137.1E 115 +36hr 10 pm March 18 3 15.9S 136.8E 145 +48hr 10 am March 19 1 16.3S 136.2E 185 +60hr 10 pm March 19 tropical low 16.5S 135.2E 210 +72hr 10 am March 20 tropical low 16.5S 133.8E 225 -
WTPS31 PGTW 170300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 19P (MEGAN) WARNING NR 007// RMKS/ 1. TROPICAL CYCLONE 19P (MEGAN) WARNING NR 007 01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 170000Z --- NEAR 14.9S 137.4E MOVEMENT PAST SIX HOURS - 190 DEGREES AT 05 KTS POSITION ACCURATE TO WITHIN 030 NM POSITION BASED ON EYE FIXED BY A COMBINATION OF SATELLITE AND RADAR PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 000 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 065 NM NORTHEAST QUADRANT 045 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 065 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 075 NM SOUTHWEST QUADRANT 105 NM NORTHWEST QUADRANT REPEAT POSIT: 14.9S 137.4E --- FORECASTS: 12 HRS, VALID AT: 171200Z --- 15.4S 137.2E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 120 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 215 DEG/ 02 KTS --- 24 HRS, VALID AT: 180000Z --- 15.8S 136.9E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 130 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 230 DEG/ 02 KTS --- 36 HRS, VALID AT: 181200Z --- 16.1S 136.5E MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND RADIUS OF 064 KT WINDS - 035 NM NORTHEAST QUADRANT 035 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 035 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 130 NM NORTHEAST QUADRANT 140 NM SOUTHEAST QUADRANT 140 NM SOUTHWEST QUADRANT 130 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 245 DEG/ 04 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 190000Z --- 16.4S 135.8E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 265 DEG/ 06 KTS --- 72 HRS, VALID AT: 200000Z --- 16.6S 133.5E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER LAND --- REMARKS: 170300Z POSITION NEAR 15.0S 137.4E. 17MAR24. TROPICAL CYCLONE 19P (MEGAN), LOCATED APPROXIMATELY 405 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA, HAS TRACKED SOUTHWARD AT 05 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 170000Z IS 968 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 170000Z IS 22 FEET. NEXT WARNINGS AT 170900Z, 171500Z, 172100Z AND 180300Z. // NNNN
WDPS31 PGTW 170300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 19P (MEGAN) WARNING NR 007// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 14.9S 137.4E INITIAL INTENSITY: 80 KTS GEOGRAPHIC REFERENCE: 405 NM EAST-SOUTHEAST OF DARWIN, AUSTRALIA MOVEMENT PAST 6 HOURS: SOUTHWARD AT 05 KTS SIGNIFICANT WAVE HEIGHT: 22 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TROPICAL CYCLONE 19P (MEGAN) HAS CONTINUED TO RAPIDLY INTENSIFY OVER THE ZESTY WATERS OF THE SOUTHERN GULF OF CARPENTARIA. AFTER ACHIEVING A VERTICALLY ALIGNED VORTEX THIS MORNING, THE SYSTEM HAS CONTINUED TO DEVELOP A STRONGER INNER-CORE OF DEEP CONVECTION, THOUGH AS OF YET HAS NOT FORMED AN EYE FEATURE IN EITHER THE VISIBLE OR INFRARED CHANNELS. THE LATEST ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS VERY DENSE INNER-CORE CONVECTIVE ACTIVITY, WITH OVERSHOOTING TOPS AND CLOUD TOP TEMPERATURES AS LOW AS -94C. ADDITIONALLY, AN EXTREMILY POTENT INNER-CORE LIGHTNING BURST IS ONGOING, WHICH IS A STRONG INDICATOR OF ADDITIONAL INTENSIFICATION IN THE OFFING. A 161958Z SSMIS 91GHZ MICROWAVE IMAGE REVEALED A WELL-DEFINED MICROWAVE EYE, THOUGH THE EYE IN THE 37GHZ BAND HAD A MUCH WEAKER REPRESENTATION. REGARDLESS, TRACKING OF THE EYE FEATURE SHOWED THAT THE SYSTEM MADE A SMALL CLOCKWISE LOOP BETWEEN 1200Z AND 2000Z AND IS NOW TRACKING TOWARDS THE SOUTHEAST. THE INITIAL POSITION WAS ASSESSED WITH MEDIUM CONFIDENCE, UNDER THE COLDEST CLOUD TOPS IN THE EIR WITH SUPPORT FROM RADAR POSITIONING DATA. THE INITIAL INTENSITY WAS ASSESSED WITH MEDIUM CONFIDENCE, ON THE HIGHER END OF THE AVAILABLE OBJECTIVE AND SUBJECTIVE FIXES NOTED BELOW. THE ENVIRONMENT REMAINS FAVORABLE, WITH LOW TO MODERATE EASTERLY ENVIRONMENTAL SHEAR, VERY WARM SSTS, HIGH OHC AND MODERATE WESTWARD AND EQUATORWARD OUTFLOW. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: WESTERN PERIPHERY OF A WEAK NEAR EQUATORIAL RIDGE (NER) TO THE EAST. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.0 - 65 KTS KNES: T4.5 - 77 KTS ADRM: T4.0 - 65 KTS CIMSS SATCON: 74 KTS AT 170000Z CIMSS ADT: 79 KTS AT 162330Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 10-15 KTS SST: 30-31 CELSIUS OUTFLOW: MODERATE EQUATORWARD OTHER FACTORS: MODERATE WESTWARD OUTFLOW. 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: TC 19P HAS COMPLETED A TIGHT CLOCKWISE LOOP OVER THE PAST SIX HOURS, HAVE ABSCONDED BRIEFLY IN A WEAK STEERING ENVIRONMENT. BUT NOW IT HAS PICKED UP SOME SPEED, HEADED TOWARDS THE SOUTHWEST COAST OF THE GULF OF CARPENTARIA, ALONG THE WESTERN SIDE OF A MID-LEVEL NER CENTERED TO THE NORTHEAST. THE NER IS EXPECTED TO WEAKEN SOMEWHAT OVER THE NEXT 12 TO 24 HOURS, WHICH WILL LOOSEN THE STEERING GRADIENT BY A NOTCH OR TWO, THUS ALLOWING TC 19P TO SLOW DOWN TO 2-3 KNOTS AS IT APPROACHES THE COAST. LANDFALL IS EXPECTED AROUND TAU 24 IN THE VICINITY OF THE SIR EDWARD PELLEW GROUP. AFTER LANDFALL, TRACK SPEEDS WILL REMAIN LOW OR EVEN SLOW A BIT MORE AS A WEAKNESS DEVELOPS IN THE MID-LEVEL RIDGE PATTERN. AFTER TAU 48 THE SYSTEM WILL BEGIN TO ACCELERATE WESTWARD AS IT COMES UNDER THE INFLUENCE OF A BUILDING SUBTROPICAL RIDGE (STR) TO THE SOUTH. IN TERMS OF INTENSITY, THE SYSTEM HAS CONTINUED TO RAPIDLY INTENSIFY, EVEN IN THE FACE OF MODERATE EASTERLY ENVIRONMENTAL SHEAR. NO SIGNIFICANT CHANGES ARE EXPECTED IN THE OVERALL ENVIRONMENT OVER THE NEXT 12 TO 18 HOURS, THUS THE SYSTEM IS FORECAST TO CONTINUE TO INTENSIFY, UP TO A PEAK OF 95 KNOTS BY TAU 12. THE SYSTEM WILL MAINTAIN THIS PEAK INTENSITY THROUGH LANDFALL EVEN AFTER DEEP-LAYER ENVIRONMENTAL SHEAR ALONG WITH A BURST OF CONVERGENT NORTHEASTERLY FLOW ALOFT, MOVES IN AROUND TAU 18. ONCE ASHORE HOWEVER, THE SYSTEM WILL QUICKLY WEAKEN AND ULTIMATELY DISSIPATE OVER NORTH-CENTRAL AUSTRALIA BY TAU 72. MODEL DISCUSSION: DETERMINISTIC TRACK GUIDANCE IS IN GOOD AGREEMENT AND HAS IMPROVED SINCE THE PREVIOUS RUN, WITH NO SIGNIFICANT OUTLIERS AT THIS TIME. THE TRACK SPREAD HAS REDUCED TO JUST 100NM BY THE END OF THE FORECAST PERIOD. HOWEVER, TRACK SPEED IS THE MORE DOMINANT CONCERN AND THERE IS A SIGNIFICANT AMOUNT OF ALONG-TRACK SPREAD, PARTICULARLY IN THE FIRST 36 HOURS OF THE FORECAST. THE JTWC FORECAST TRACKS CLOSE TO THE CONSENSUS MEAN IN BOTH DIRECTION AND SPEED, BUT CONFIDENCE IS ONLY MEDIUM DUE TO THE POSSIBILITY OF A FASTER SPEED OF ADVANCE IN THE FIRST 36 HOURS OF THE FORECAST. INTENSITY GUIDANCE REMAINS MIXED, WITH THE MESOSCALE MODELS (HWRF, HAFS-A, AND COAMPS-TC) STUBBORNLY REFUSING TO ACKNOWLEDGE THE POSSIBILITY OF ADDITIONAL INTENSIFICATION, AS THEY HAVE BEEN DOING SINCE YESTERDAY. THE MESOSCALE MOELS ALL SHOW THE SYSTEM MAINTAINING INTENSITY TO TAU 12 THEN FALLING OFF SHARPLY THEREAFTER. MEANWHILE, THE SHIPS GUIDANCE (BOTH GFS AND NAVGEM) SHOW AN ADDITIONAL 15-20 KNOTS OF INTENSIFICATION, PEAKING AT 100 KTS, WHILE THE FRIA, RICN, RIPA AND RI25 TO RI 35 RAPID INTENSIFICATION AIDS CONTINUE TO TRIGGER, PEAKING THE SYSTEM NEAR 125 KNOTS BY TAU 24. IF THE SYSTEM HAD MORE TIME OVER WATER, THE RI PEAKS MIGHT BE REALISTIC, BUT WITH REALISTICALLY NO MORE THAN 12 HOURS OF OPEN WATERS, THE JTWC FORECAST PEAKS AT 95 KNOTS. FORECAST CONFIDENCE: TRACK 0 - 72 HR: MEDIUM INTENSITY 0 - 72 HR: MEDIUM// NNNN
最后于 2024-03-17 11:30:00 被ygsj24编辑 ，原因：