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AXAU01 APRF 201930 IDW27600 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 1930 UTC 20/03/2024 Name: Tropical Cyclone Neville Identifier: 08U Data At: 1800 UTC Latitude: 17.7S Longitude: 107.9E Location Accuracy: within 20nm (35 km) Movement Towards: west (270 deg) Speed of Movement: 8 knots (14 km/h) Maximum 10-Minute Wind: 50 knots (95 km/h) Maximum 3-Second Wind Gust: 70 knots (130 km/h) Central Pressure: 989 hPa Radius of 34-knot winds NE quadrant: 30 nm (55 km) Radius of 34-knot winds SE quadrant: 50 nm (95 km) Radius of 34-knot winds SW quadrant: 50 nm (95 km) Radius of 34-knot winds NW quadrant: 30 nm (55 km) Radius of 48-knot winds NE quadrant: Radius of 48-knot winds SE quadrant: 20 nm (35 km) Radius of 48-knot winds SW quadrant: 20 nm (35 km) Radius of 48-knot winds NW quadrant: 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: 1006 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: 21/0000: 17.7S 107.0E: 030 (060): 060 (110): 983 +12: 21/0600: 17.8S 106.0E: 040 (075): 065 (120): 979 +18: 21/1200: 17.7S 105.1E: 045 (085): 065 (120): 979 +24: 21/1800: 17.6S 103.9E: 050 (090): 070 (130): 976 +36: 22/0600: 17.7S 101.2E: 055 (105): 070 (130): 977 +48: 22/1800: 18.3S 98.4E: 075 (140): 070 (130): 974 +60: 23/0600: 19.3S 95.2E: 095 (180): 065 (120): 978 +72: 23/1800: 20.4S 92.4E: 120 (225): 055 (100): 985 +96: 24/1800: 21.8S 87.6E: 170 (315): 035 (065): 998 +120: 25/1800: 24.5S 85.7E: 205 (380): 030 (055): 1000 REMARKS: Tropical Cyclone Neville has intensified in the past 6-12 hours. Position well defined on EIR assisted by ASCAT at 15UTC and earlier microwave imagery 1122UTC SSMIS. Microwave imagery has shown an impressive eye signature. Intensity estimated at 50kn based upon ASCAT-B at 1455UTC HiRES solution supported by SATCON, balanced between Dvorak / microwave patterns (higher) and earlier scatterometer/radiometer winds (lower). Indeed winds from HSCAT 1006UTC, AMSR2 0626UTC and earlier ASCAT at 0227 and 0139 UTC did not show gales when the cloud features would have suggested higher winds. Dvorak analysis: DT =4.0 based on EIR eye pattern (MG surround adjusted down for MG/LG eye) and 1.0+ curved band and adjusted MET=4.0 based on D 24h trend, with +0.5 PAT adjustment. FT/CI=4.0. Recent objective guidance is mixed : SATCON 55kn; ADT 51kn CI=3.3 but raw numbers based on eye pattern are 4.5-5.5; AiDT 40kn and DPRINT 63kn (all 1-min average). Wind structure is based on ASCAT with maximum winds and gale extent to the south, and RMW=15nm. Neville is pouched in a moist environment surrounded by dry air. CIMSS upper wind analyses indicate that vertical shear has reduced to 10-15kn NE'ly. The strong microwave signature would indicate a stronger system but cloud tops are not so cold perhaps reflecting the moderate ocean temperatures (~27C). An upper trough to the south has also increased poleward outflow aloft over the last 24 hours. Further intensification is forecast in line with most NWP guidance although there is considerable spread as to the extent of this. The forecast track takes it over slightly cooler waters which is an impediment to rapid development. Otherwise the low vertical wind shear should protect the inner circulation from penetration of the surrounding dry air. A more well-defined eye would lead to a more rapid intensification but moderate cloud top temperatures would suggest that a category 4 peak is not likely. A steering ridge to the south should ensure a consistent westerly track but in the longer term the ridge should weaken and Neville is forecast to recurve to the southwest and weaken as it moves over cooler SSTs and is possibly affected by increasing vertical wind shear. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 21/0130 UTC.
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Time (AWST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 2 am March 21 2 17.7S 107.9E 35 +6hr 8 am March 21 2 17.7S 107.0E 60 +12hr 2 pm March 21 3 17.8S 106.0E 75 +18hr 8 pm March 21 3 17.7S 105.1E 85 +24hr 2 am March 22 3 17.6S 103.9E 90 +36hr 2 pm March 22 3 17.7S 101.2E 105 +48hr 2 am March 23 3 18.3S 98.4E 140 +60hr 2 pm March 23 3 19.3S 95.2E 180 +72hr 2 am March 24 2 20.4S 92.4E 225 -
WTXS31 PGTW 202100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 033// RMKS/ 1. TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 033 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 201800Z --- NEAR 17.9S 107.9E MOVEMENT PAST SIX HOURS - 265 DEGREES AT 09 KTS POSITION ACCURATE TO WITHIN 060 NM POSITION BASED ON CENTER LOCATED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT REPEAT POSIT: 17.9S 107.9E --- FORECASTS: 12 HRS, VALID AT: 210600Z --- 17.8S 105.9E MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 270 DEG/ 10 KTS --- 24 HRS, VALID AT: 211800Z --- 17.8S 103.7E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 070 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 265 DEG/ 12 KTS --- 36 HRS, VALID AT: 220600Z --- 18.0S 101.1E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 110 NM SOUTHEAST QUADRANT 110 NM SOUTHWEST QUADRANT 090 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 260 DEG/ 14 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 221800Z --- 18.5S 98.3E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 050 NM NORTHEAST QUADRANT 060 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT 130 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 100 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 245 DEG/ 14 KTS --- 72 HRS, VALID AT: 231800Z --- 20.7S 92.8E MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT 120 NM SOUTHEAST QUADRANT 120 NM SOUTHWEST QUADRANT 080 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 250 DEG/ 11 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 241800Z --- 22.1S 88.5E MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 080 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 100 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 235 DEG/ 09 KTS --- 120 HRS, VALID AT: 251800Z --- 24.3S 85.3E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 202100Z POSITION NEAR 17.9S 107.4E. 20MAR24. TROPICAL CYCLONE 18S (NEVILLE), LOCATED APPROXIMATELY 438 NM NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED WESTWARD AT 09 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 201800Z IS 989 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 201800Z IS 19 FEET. NEXT WARNINGS AT 210900Z AND 212100Z. // NNNN
WDXS31 PGTW 202100 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 033// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 17.9S 107.9E INITIAL INTENSITY: 60 KTS GEOGRAPHIC REFERENCE: 438 NM NORTHWEST OF LEARMONTH, AUSTRALIA MOVEMENT PAST 6 HOURS: WESTWARD AT 09 KTS SIGNIFICANT WAVE HEIGHT: 19 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY DEPICTS TROPICAL CYCLONE(TC) 18S WITH A RAGGED, PINHOLE EYE FEATURE AND WELL-DEFINED CONVECTIVE CLOUD BANDS WRAPPING INTO THE CENTER. BASED ON MICROWAVE IMAGERY, IT APPEARS THAT THE VORTEX IS WELL ORGANIZED IN THE UPPER-LEVELS BUT DOES NOT FULLY EXTEND TO THE LOW LEVELS AS DEPICTED IN AN EARLIER 201124Z 37GHZ SSMIS IMAGE. THE SYSTEM IS CURRENTLY BEING STEERED ON THE NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE SOUTH. CURRENTLY THE SYSTEM IS IN FAVORABLE SEA SURFACE TEMPERATURES (SST) OF 26C. MILD AMOUNTS OF VERTICAL WIND SHEAR (VWS) FROM THE NORTHEAST SLIGHTLY CHALLENGE THE VORTEX. THE MOIST CORE IS CURRENTLY SELF-SUSTAINING WHILE SWADDLED BY DRY AIR THAT HAS YET TO PENETRATE THE CORE. UPPER-LEVEL OUTFLOW IS RADIAL, BUT RELATIVELY CONSTRAINED TO THE IMMEDIATE VICINITY OF THE SYSTEM, WITH NO OUTFLOW CHANNELS. THE INITIAL POSITION WAS ASSESSED WITH HIGH CONFIDENCE BASED ON ANIMATED EIR DEPICTING A CLEAR UPPER-LEVEL CORE SURROUNDED BY BANDING. THE INITIAL INTENSITY WAS ASSESSED WITH HIGH CONFIDENCE BASED ON A 201454Z ULTRA-HIGH RESOLUTION (UHR) METOP-B WIND SPEED PRODUCT DEPICTING 50-60KT WINDS IN THE NORTHERN HEMISPHERE. INITIAL WIND RADII BASIS: SCATTEROMETER DATA CURRENT STEERING MECHANISM: THE NORTHERN PERIPHERY OF A STR TO THE SOUTH. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.0 - 65 KTS KNES: T4.5 - 77 KTS DEMS: T3.5 - 55 KTS APRF: T4.0 - 65 KTS CIMSS SATCON: 58 KTS AT 201900Z CIMSS ADT: 51 KTS AT 201800Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 10-15 KTS SST: 26-27 CELSIUS OUTFLOW: MODERATE RADIAL ANALYSIS CONFIDENCE: INITIAL POSITION: HIGH INITIAL INTENSITY: HIGH 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 18S IS FORECAST TO CONTINUE TO TRACK WEST THROUGH TAU 36 BEFORE CURVING TO THE WEST-SOUTHWEST AS IT BEGINS TO ROUND THE STR THROUGH THE END OF THE FORECAST PERIOD. IN TERMS OF INTENSITY, THE SYSTEM IS FORECAST TO REMAIN IN A SELF-SUSTAINING MOIST POCKET SURROUNDED BY DRY AIR, ALLOWING THE SYSTEM TO SUSTAIN GRADUAL INTENSIFICATION FOR THE FIRST 24 HOURS. BY TAU 24, THE JET MAXIMUM TO THE SOUTH IS FORECAST TO AMPLIFY UPPER-LEVEL DIVERGENCE AND SIGNIFICANTLY IMPROVE POLEWARD OUTFLOW, LEADING TO MORE RAPID INTENSIFICATION THROUGH TAU 48. AFTER 48 HOURS, VWS IS FORECAST TO INCREASE TO MODERATE AND HIGH LEVELS, COUNTERING THE IMPROVEMENT OF POLEWARD OUTFLOW, AND CAUSING DRY AIR TO SMOTHER THE VORTEX. THERE IS A POTENTIAL FOR A BRIEF PERIOD OF SUBTROPICAL INFLUENCE ON TC 18S, AS IT INTERACTS WITH A MID-LATITUDE UPPER-LEVEL TROUGH. THE SYSTEM WILL LIKELY BEGIN THE EARLY PHASES OF SUBTROPICAL TRANSITION (STT) BETWEEN TAU 96 AND TAU 120, BUT IT IS EXPECTED TO COMPLETELY DISSIPATE BEFORE STT CAN COMPLETE. MODEL DISCUSSION: DETERMINISTIC MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGH TAU 72 THAT TC 18S WILL CONTINUE TO CURVE WEST AND THEN SLOWLY WEST-SOUTHWEST AS IT ROUNDS A STR TO THE SOUTH. HOWEVER, IN THE LATER PORTION OF THE FORECAST, THE MODEL GUIDANCE DIVERGES SHARPLY, WITH THE GALWEM AND UKMET TRACKING THE SYSTEM ALMOST DUE WEST THROUGH THE END OF THE FORECAST, WHILE THE GFS DIVES SHARPLY SOUTHWARD, LEADING TO A 630NM SPREAD BY TAU 120. THE JTWC FORECAST LIES JUST SOUTH OF THE MULTI-MODEL CONSENSUS MEAN, WITH HIGH CONFIDENCE THROUGH TAU 72, TRENDING TO LOW CONFIDENCE IN THE EXTENDED FORECAST. THE JTWC INTENSITY GUIDANCE IS IN GOOD AGREEMENT AS WELL THAT THERE WILL BE INTENSIFICATION THROUGH TAU 48 BEFORE WEAKENING, BUT THERE IS DISAGREEMENT IN TERMS OF EXACTLY HOW MUCH. HWRF REFLECTS A PEAK OF 105KTS, BUT GFS ONLY FORECASTS A PEAK OF 70KTS. COAMPS-TC IS THE ONLY STARK OUTLIER AND FORECASTS THAT THE SYSTEM WILL NOT INTENSIFY AT ALL AND COMPLETELY DISSIPATE BY TAU 96. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: LOW INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN
最后于 2024-03-21 06:00:00 被ygsj24编辑 ，原因： -
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AXAU01 APRF 210126 IDW27600 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 0126 UTC 21/03/2024 Name: Severe Tropical Cyclone Neville Identifier: 08U Data At: 0000 UTC Latitude: 17.9S Longitude: 106.9E Location Accuracy: within 15nm (30 km) Movement Towards: west southwest (258 deg) Speed of Movement: 10 knots (18 km/h) Maximum 10-Minute Wind: 65 knots (120 km/h) Maximum 3-Second Wind Gust: 90 knots (165 km/h) Central Pressure: 982 hPa Radius of 34-knot winds NE quadrant: 40 nm (75 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: 50 nm (95 km) Radius of 48-knot winds NE quadrant: 20 nm (35 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: 30 nm (55 km) Radius of 64-knot winds: nm ( km) Radius of Maximum Winds: 15 nm (30 km) Dvorak Intensity Code: T4.5/4.5/D2.0/24HRS STT:D0.5/06HRS Pressure of outermost isobar: 1008 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: 21/0600: 17.9S 105.9E: 030 (055): 065 (120): 981 +12: 21/1200: 17.8S 104.9E: 040 (070): 070 (130): 977 +18: 21/1800: 17.8S 103.7E: 045 (080): 075 (140): 974 +24: 22/0000: 17.7S 102.5E: 050 (090): 080 (150): 970 +36: 22/1200: 18.0S 99.7E: 060 (110): 085 (155): 963 +48: 23/0000: 18.7S 96.5E: 085 (155): 085 (155): 963 +60: 23/1200: 19.7S 93.4E: 100 (190): 070 (130): 976 +72: 24/0000: 20.7S 90.6E: 125 (230): 060 (110): 983 +96: 25/0000: 22.1S 85.8E: 180 (330): 030 (055): 1003 +120: 26/0000: 25.8S 86.0E: 225 (415): 030 (055): 1001 REMARKS: Severe Tropical Cyclone Neville has intensified in the past 6-12 hours through the diurnally favourable period. Position well defined on EIR assisted by SSMIS microwave pass at ~2230UTC. Microwave imagery has shown an impressive eye signature. In the three hours up to 0000UTC Neville had a well-defined eye which has been obscured closer to analysis time. Intensity estimated at 65kn based upon subjective Dvorak and recent DPRINT whilst also supported by ADT raw values. Dvorak analysis: DT =4.5 based on EIR eye pattern 3-hour average (DG surround no adjustment OW/LG eye). This is consistent with MET=4.0 based on D+ 24h trend, with +0.5 PAT adjustment. FT/CI=4.5. Recent objective guidance is mixed : SATCON 58kn; ADT 55kn CI=3.3 but raw numbers based on eye pattern are 4.5-5.5; AiDT 49kn and DPRINT 71kn (all 1-min average). Wind structure has been adjusted for recent extension in NW quadrant with deeper convection, but otherwise is maintained from previous analysis with no significant change in structure in microwave or EIR satellite to suggest a change. Maximum winds and gale extent to the south, and RMW=15nm. Neville is pouched in a moist environment surrounded by dry air. CIMSS upper wind analyses indicate that vertical shear has reduced to 10-15kn NE'ly. Further intensification is forecast in line with most NWP guidance although there is considerable spread as to the extent of this. The forecast track takes it over slightly cooler waters which is an impediment to rapid development. Otherwise the low vertical wind shear should protect the inner circulation from penetration of the surrounding dry air. A more well-defined eye would lead to a more rapid intensification but moderate cloud top temperatures would suggest that a category 4 peak is not likely. A steering ridge to the south should ensure a consistent westerly track but in the longer term the ridge should weaken and Neville is forecast to turn to the southwest and then southeast by which time it is forecast to weaken rapidly as it moves over cooler SSTs and is affected by increasing vertical wind shear. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 21/0730 UTC.
Time (AWST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 8 am March 21 3 17.9S 106.9E 30 +6hr 2 pm March 21 3 17.9S 105.9E 55 +12hr 8 pm March 21 3 17.8S 104.9E 70 +18hr 2 am March 22 3 17.8S 103.7E 80 +24hr 8 am March 22 3 17.7S 102.5E 90 +36hr 8 pm March 22 3 18.0S 99.7E 110 +48hr 8 am March 23 3 18.7S 96.5E 155 +60hr 8 pm March 23 3 19.7S 93.4E 190 +72hr 8 am March 24 2 20.7S 90.6E 230 -
WTXS31 PGTW 210300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 034// RMKS/ 1. TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 034 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 210000Z --- NEAR 17.9S 106.7E MOVEMENT PAST SIX HOURS - 270 DEGREES AT 11 KTS POSITION ACCURATE TO WITHIN 040 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT REPEAT POSIT: 17.9S 106.7E --- FORECASTS: 12 HRS, VALID AT: 211200Z --- 17.9S 104.4E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 265 DEG/ 10 KTS --- 24 HRS, VALID AT: 220000Z --- 18.0S 102.2E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 265 DEG/ 13 KTS --- 36 HRS, VALID AT: 221200Z --- 18.3S 99.5E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 255 DEG/ 14 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 230000Z --- 19.0S 96.6E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 070 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 250 DEG/ 13 KTS --- 72 HRS, VALID AT: 240000Z --- 20.8S 91.5E MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 000 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 040 NM NORTHEAST QUADRANT 070 NM SOUTHEAST QUADRANT 060 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 245 DEG/ 10 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 250000Z --- 22.5S 87.7E MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 120 HR POSIT: 205 DEG/ 12 KTS --- 120 HRS, VALID AT: 260000Z --- 26.7S 85.3E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 210300Z POSITION NEAR 17.9S 106.1E. 21MAR24. TROPICAL CYCLONE 18S (NEVILLE), LOCATED APPROXIMATELY 493 NM WEST-NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED WESTWARD AT 11 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 210000Z IS 983 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210000Z IS 24 FEET. NEXT WARNINGS AT 210900Z, 211500Z, 212100Z AND 220300Z. // NNNN
WDXS31 PGTW 210300 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 034// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 17.9S 106.7E INITIAL INTENSITY: 70 KTS GEOGRAPHIC REFERENCE: 493 NM WEST-NORTHWEST OF LEARMONTH, AUSTRALIA MOVEMENT PAST 6 HOURS: WESTWARD AT 11 KTS SIGNIFICANT WAVE HEIGHT: 24 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: TROPICAL CYCLONE (TC) 19S (NEVILLE) CONTINUES TO INTENSIFY IN THE OPEN WATERS NORTHWEST OF LEARMOUTH. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A COMPACT STORM, WITH FLARING DEEP CONVECTION PARTIALLY SURROUNDING A CYCLING EYE FEATURE. THE MOST RECENT ENHANCED INFRARED (EIR) SATELLITE LOOP SHOWS THAT THE EYE WAS VERY WELL-DEFINED AROUND 2230Z, WHEN THE OBJECTIVE FIX ESTIMATES PEAKED, THEN FILLED IN BY THE 210000Z HOUR BEFORE ONCE AGAIN STARTING TO APPEAR AS OF 210130Z. A 202237Z SSMIS 91GHZ MICROWAVE IMAGE SHOWED A WELL-DEFINED MICROWAVE EYE FEATURE, WITH A SEGMENTED EYEWALL, BROKEN IN THE NORTHEAST QUADRANT WHICH FACES THE SHEAR VECTOR. THE INITIAL POSITION WAS ASSESSED WITH HIGH CONFIDENCE BASED ON THE RAGGED EYE FEATURE IN THE EIR AND EXTRAPOLATION OF THE AFOREMENTIONED MICROWAVE EYE. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE, HEDGED SLIGHTLY BELOW THE CONSENSUS OF AGENCY FIXES AT T4.5 (77 KTS) IN LIGHT OF THE SLIGHTLY LOWER DPRINT ESTIMATE OF 71 KTS. ADT AND AIDT VALUES HAVE BEEN DISCOUNTED DUE TO THE LARGE VARIABILITY SEEN IN THE RAW ESTIMATES WHICH ARE DRIVEN BY THE SMALL SIZE OF THE INNER CORE AND THE VARIABILITY IN THE EYE STRUCTURE. ANALYSIS REVEALS A FAVORABLE ENVIRONMENT, WITH LOW VWS, WARM SSTS AND GOOD RADIAL OUTFLOW. DRY AIR SURROUNDS THE SYSTEM, BUT LIKE A JOEY, TC NEVILLE REMAINS SAFELY TUCKED IN A POUCH OF MOISTURE, NURTURING AND SUPPORTING IT. OUTFLOW IS GOOD OVERALL BUT REMAINS CONSTRAINED TO THE IMMEDIATE SURROUNDINGS WITH NO OUTFLOW CHANNELS. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE SOUTH. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T4.5 - 77 KTS KNES: T4.5 - 77 KTS APRF: T4.5 - 77 KTS CIMSS ADT: 55 KTS AT 202330Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 5-10 KTS SST: 27-28 CELSIUS OUTFLOW: MODERATE RADIAL 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 19S IS FORECAST TO CONTINUE TRACKING WESTWARD OVER THE NEXT 24 HOURS ALONG THE NORTHERN SIDE OF AN EAST-WEST ORIENTED STR TO THE SOUTH. AFTER TAU 36, THE SYSTEM WILL BEGIN TO TRACK WEST-SOUTHWEST, THEN SOUTHWEST THROUGH TAU 96, BEFORE TURNING SOUTHWARD BY THE END OF THE FORECAST, AS IT ROUNDS THE STR AXIS. IN TERMS OF INTENSITY, WHILE THE SYSTEM REMAINS EXTREMELY COMPACT, OUTFLOW ALOFT IS LIMITED IN AREAL EXTENT AND THE SYSTEM IS CUT-OFF FROM ANY SIGNIFICANT OUTFLOW MECHANISMS, IT IS FORECAST TO CONTINUE INTENSIFYING STEADILY FOR THE NEXT 12 TO 24 HOURS. BY TAU 36, THE SYSTEM BEGINS TO TAP INTO A DIVERGENT POLEWARD OUTFLOW CHANNEL, AHEAD OF 200MB TROUGH APPROACHING FROM THE WEST. THIS WILL ALLOW FOR A BURST OF INTENSIFICATION UP TO THE PEAK OF AT LEAST 95 KTS BY TAU 36. BY TAU 72, SHEAR AND CONVERGENCE ALOFT IS FORECAST TO DRAMATICALLY INCREASE AS THE SYSTEM MOVES INTO THE LEFT-REAR ENTRANCE REGION OF A 100 KT JET MAX TO THE SOUTH, RESULTING IN A RAPID DECAPITATION OF THE VORTEX. THOUGH THE SYSTEM WILL BEGIN THE EARLY PHASES OF SUBTROPICAL TRANSITION (STT) BY TAU 96, THE SYSTEM IS FORECAST TO RAPIDLY WEAKEN AND DISSIPATE BEFORE COMPLETING STT. MODEL DISCUSSION: DETERMINISTIC TRACK GUIDANCE IS IN GENERAL AGREEMENT ON THE OVERALL TRACK SCENARIO, BUT DIFFERS IN THE TIMING AND STRENGTH OF THE TURN SOUTHWARD. THE GFS AND THE GEFS ENSEMBLE MEAN LEAD THE PACK IN TURNING THE SYSTEM SHARPLY SOUTHWARD AT TAU 96, THEN ACCELERATING SOUTHEASTWARD TO A POSITION NEAR 35S. MEANWHILE THE GALWEM AND UKMET TRACK THE SYSTEM SLOWLY WEST-SOUTHWEST, LEADING TO A 1100NM SPREAD IN POSSIBLE TRACK SOLUTIONS BY TAU 120. THE REMAINDER OF THE CONSENSUS MEMBERS INCLUDING NAVGEM, AND ECMWF ARE MUCH CLOSER TO THE CONSENSUS MEAN TRACK. THE JTWC FORECAST LIES SOUTH AND EAST OF THE CONSENSUS, BUT HEDGED TOWARDS THE ECMWF TRACK. THROUGH TAU 72, CONFIDENCE IS FAIRLY GOOD BUT QUICKLY DEGRADES TO LOW DUE TO THE HIGH UNCERTAINTY IN THE TRACKERS TO TAU 120. INTENSITY GUIDANCE IS BECOMING MORE UNCERTAIN, WITH THE BULK OF THE GUIDANCE NOW SUGGESTING LIMITED ADDITIONAL INTENSIFICATION THROUGH TAU 60, FOLLOWED BY RAPID WEAKENING THEREAFTER. THE ONLY OUTLIER IS THE HAFS-A WHICH SHOWS A PEAK OF 110 KTS AT TAU 48. THE JTWC FORECAST IS 10 KTS HIGHER THAN THE CONSENSUS WITH MEDIUM CONFIDENCE. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: LOW INTENSITY 0 - 72 HR: MEDIUM INTENSITY 72-120 HR: MEDIUM// NNNN
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全球热带气旋监测公报
澳大利亚附近海域三级强热带气旋“纳维尔”生成
时 间：21日08时（北京时）
海 域：澳大利亚附近海域
命 名：“纳维尔”，NEVILLE
中心位置：南纬17.9度、东经106.9度
强度等级：三级强热带气旋
最大风力：12级（33米/秒，相当于我国的台风级）
中心气压：982百帕
参考位置：科科斯群岛东偏南方向约1250公里的洋面上
变化过程：“纳维尔”生成并加强到12级
预报结论：“纳维尔”将以每小时15-20公里的速度向偏西方向移动，强度逐渐加强。
图1 卫星红外监测图像（北京时间2024年03月21日08时00分）
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AXAU01 APRF 210700 IDW27600 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 0700 UTC 21/03/2024 Name: Severe Tropical Cyclone Neville Identifier: 08U Data At: 0600 UTC Latitude: 17.9S Longitude: 105.8E Location Accuracy: within 15nm (30 km) Movement Towards: west (270 deg) Speed of Movement: 10 knots (19 km/h) Maximum 10-Minute Wind: 70 knots (130 km/h) Maximum 3-Second Wind Gust: 100 knots (185 km/h) Central Pressure: 976 hPa Radius of 34-knot winds NE quadrant: 40 nm (75 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: 50 nm (95 km) Radius of 48-knot winds NE quadrant: 25 nm (45 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: 30 nm (55 km) Radius of 64-knot winds: nm ( km) Radius of Maximum Winds: 15 nm (30 km) Dvorak Intensity Code: T4.5/4.5/D1.5/24HRS STT:S0.0/06HRS Pressure of outermost isobar: 1006 hPa Radius of outermost closed isobar: 160 nm (295 km) FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure (UTC) : degrees : nm (km): knots(km/h): hPa +06: 21/1200: 17.8S 104.8E: 030 (055): 075 (140): 971 +12: 21/1800: 17.7S 103.6E: 040 (075): 085 (155): 963 +18: 22/0000: 17.7S 102.4E: 045 (085): 090 (165): 959 +24: 22/0600: 17.8S 101.0E: 055 (100): 095 (175): 954 +36: 22/1800: 18.3S 98.0E: 065 (125): 095 (175): 952 +48: 23/0600: 19.2S 94.8E: 085 (160): 090 (165): 957 +60: 23/1800: 20.3S 91.9E: 110 (200): 070 (130): 973 +72: 24/0600: 21.0S 89.1E: 135 (250): 050 (095): 988 +96: 25/0600: 22.7S 85.0E: 195 (360): 030 (055): 1002 +120: 26/0600: 27.1S 87.2E: 290 (535): 030 (055): 1000 REMARKS: Severe Tropical Cyclone Neville continues to show signs of development. Although it has shown a fluctuating eye there has been a greater extent of cold cloud tops associated with the system centre and convection today. Position well defined on VIS and EIR. Microwave imagery has shown an impressive eye signature in deep convection, however no high resolution low level (36-37 GHz) passes have scanned the system recently. In the three hours up to 0600UTC Neville had an eye surrounded by very cold cloud tops (black to white in the Dvorak scale). This eye has been obscured closer to analysis time. Intensity estimated at 70kn based upon subjective Dvorak and recent DPRINT, in addition to a trend forecast from this morning as the system has shown an increase in convection both in terms of spatial (surrounding the system including the weaker modelled northern side) and deeper with a larger extent of colder cloud tops. Dvorak analysis: DT =4.5 based on EIR eye pattern/VIS curved band 3-hour average. This is consistent with MET/PAT=4.5 based on D+ 24h trend. FT/CI=4.5. Objective guidance is very limited: No recent SATCON; ADT struggling to resolve the correct scene (uniform/embedded) 53kn CI=3.4; AiDT 45kn. The DPRINT 76kn (1-min average) objective guidance is consistent with analysis. Wind structure has the hurricane force (>64kn) winds extending to all quadrants due to the deep convection wrapping that has been observed over the past 3-6 hours. Otherwise structure is largely maintained from previous forecasts with slight asymmetry present favouring winds on the southern side. RMW=15nm. Neville is pouched in a moist environment surrounded by dry air. CIMSS upper wind analyses indicate that vertical shear has reduced to 10-12kn NE'ly. Further intensification is forecast in line with most NWP guidance although there is considerable spread as to the extent of this. Also worth noting that model guidance is not analysing Neville to be as strong at model initialisation which is likely to impact the intensity forecast from models. The main inhibiting factors for rapid intensification are relatively weak upper outflow and only moderate SSTs. Factors in favour of rapid intensification are small system size and low shear environment which protects the system from the surrounding dry air. A more well-defined eye could lead to a more rapid intensification and the development of colder cloud tops during the diurnally less favourable period today suggests that intensification to category 4 is now more likely than not. Category 5 intensity could be reached later on Friday or early Saturday, however is deemed unlikely. A steering ridge to the south should ensure a consistent westerly track but in the longer term the ridge should weaken and Neville is forecast to turn to the southwest and then southeast. As it moves to the south it is forecast to weaken rapidly as it moves over cooler SSTs and is affected by increasing vertical wind shear and begins to ingest the surrounding dry air. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 21/1330 UTC.
Time (AWST) Intensity Category Latitude
(decimal deg.)Longitude
(decimal deg.)Estimated Position
Accuracy (km)0hr 2 pm March 21 3 17.9S 105.8E 30 +6hr 8 pm March 21 3 17.8S 104.8E 55 +12hr 2 am March 22 3 17.7S 103.6E 75 +18hr 8 am March 22 4 17.7S 102.4E 85 +24hr 2 pm March 22 4 17.8S 101.0E 100 +36hr 2 am March 23 4 18.3S 98.0E 125 +48hr 2 pm March 23 4 19.2S 94.8E 160 +60hr 2 am March 24 3 20.3S 91.9E 200 +72hr 2 pm March 24 2 21.0S 89.1E 250 -
WTXS31 PGTW 210900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 035// RMKS/ 1. TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 035 01 ACTIVE TROPICAL CYCLONE IN SOUTHIO MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE WIND RADII VALID OVER OPEN WATER ONLY --- WARNING POSITION: 210600Z --- NEAR 17.8S 105.7E MOVEMENT PAST SIX HOURS - 275 DEGREES AT 10 KTS POSITION ACCURATE TO WITHIN 020 NM POSITION BASED ON EYE FIXED BY SATELLITE PRESENT WIND DISTRIBUTION: MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT 015 NM SOUTHEAST QUADRANT 015 NM SOUTHWEST QUADRANT 015 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 025 NM SOUTHEAST QUADRANT 025 NM SOUTHWEST QUADRANT 030 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 055 NM SOUTHEAST QUADRANT 045 NM SOUTHWEST QUADRANT 060 NM NORTHWEST QUADRANT REPEAT POSIT: 17.8S 105.7E --- FORECASTS: 12 HRS, VALID AT: 211800Z --- 17.8S 103.4E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 080 NM SOUTHEAST QUADRANT 070 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 24 HR POSIT: 265 DEG/ 13 KTS --- 24 HRS, VALID AT: 220600Z --- 17.9S 100.7E MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 050 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 050 NM NORTHWEST QUADRANT VECTOR TO 36 HR POSIT: 260 DEG/ 14 KTS --- 36 HRS, VALID AT: 221800Z --- 18.3S 97.8E MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT 020 NM SOUTHEAST QUADRANT 020 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT 030 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 100 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 48 HR POSIT: 255 DEG/ 15 KTS --- EXTENDED OUTLOOK: 48 HRS, VALID AT: 230600Z --- 19.1S 94.7E MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT WIND RADII VALID OVER OPEN WATER ONLY RADIUS OF 064 KT WINDS - 000 NM NORTHEAST QUADRANT 010 NM SOUTHEAST QUADRANT 010 NM SOUTHWEST QUADRANT 010 NM NORTHWEST QUADRANT RADIUS OF 050 KT WINDS - 020 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 030 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 060 NM NORTHEAST QUADRANT 090 NM SOUTHEAST QUADRANT 080 NM SOUTHWEST QUADRANT 040 NM NORTHWEST QUADRANT VECTOR TO 72 HR POSIT: 250 DEG/ 14 KTS --- 72 HRS, VALID AT: 240600Z --- 20.8S 89.0E MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATING AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER RADIUS OF 050 KT WINDS - 000 NM NORTHEAST QUADRANT 040 NM SOUTHEAST QUADRANT 040 NM SOUTHWEST QUADRANT 000 NM NORTHWEST QUADRANT RADIUS OF 034 KT WINDS - 030 NM NORTHEAST QUADRANT 050 NM SOUTHEAST QUADRANT 050 NM SOUTHWEST QUADRANT 020 NM NORTHWEST QUADRANT VECTOR TO 96 HR POSIT: 250 DEG/ 12 KTS --- LONG RANGE OUTLOOK: --- 96 HRS, VALID AT: 250600Z --- 22.3S 84.3E MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT WIND RADII VALID OVER OPEN WATER ONLY DISSIPATED AS A SIGNIFICANT TROPICAL CYCLONE OVER WATER --- REMARKS: 210900Z POSITION NEAR 17.8S 105.1E. 21MAR24. TROPICAL CYCLONE 18S (NEVILLE), LOCATED APPROXIMATELY 545 NM WEST-NORTHWEST OF LEARMONTH, AUSTRALIA, HAS TRACKED WESTWARD AT 10 KNOTS OVER THE PAST SIX HOURS. MINIMUM CENTRAL PRESSURE AT 210600Z IS 972 MB. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 210600Z IS 27 FEET. NEXT WARNINGS AT 211500Z, 212100Z, 220300Z AND 220900Z.// NNNN
WDXS31 PGTW 210900 MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI// SUBJ/PROGNOSTIC REASONING FOR TROPICAL CYCLONE 18S (NEVILLE) WARNING NR 035// RMKS/ 1. FOR METEOROLOGISTS. 2. 6 HOUR SUMMARY AND ANALYSIS. SUMMARY: INITIAL POSITION: 17.8S 105.7E INITIAL INTENSITY: 85 KTS GEOGRAPHIC REFERENCE: 545 NM WEST-NORTHWEST OF LEARMONTH, AUSTRALIA MOVEMENT PAST 6 HOURS: WESTWARD AT 10 KTS SIGNIFICANT WAVE HEIGHT: 27 FEET SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION: ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS TROPICAL CYCLONE (TC) 18S WITH PERSISTENT DEEP CONVECTION OVER ASSESSED LOW-LEVEL CIRCULATION CENTER (LLCC) ALONG WITH A DIMPLED RAGGED EYE FEATURE AND WELL-DEFINED CONVECTIVE BANDING WRAPPING INTO THE SYSTEM. THE CURRENT ENVIRONMENT IS ASSESSED AS FAVORABLE CHARACTERIZED BY MODERATE RADIAL OUTFLOW ALOFT, LOW (0-5 KTS) VERTICAL WIND SHEAR (VWS), AND WARM (27- 28 C) SEA SURFACE TEMPERATURES. MODELS SUGGEST THAT THE CORE OF THE VORTEX HAS REMAINED MOIST AND IS SUCCESSFULLY RESISTING DRY AIR ENTRAINMENT. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON A 210600Z HIMAWARI-9 VISIBLE (1KM) SATELLITE IMAGE. THE INITIAL INTENSITY IS ASSESSED WITH MEDIUM CONFIDENCE BASED ON THE SUBJECTIVE AND OBJECTIVE INTENSITY ESTIMATES LISTED BELOW. INITIAL WIND RADII BASIS: PERSISTENCE CURRENT STEERING MECHANISM: NORTHERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) TO THE SOUTH. AGENCY DVORAK AND AUTOMATED FIXES: PGTW: T5.0 - 90 KTS KNES: T5.5 - 102 KTS APRF: T4.5 - 77 KTS CIMSS DPRINT: 84 KTS AT 210700Z FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE VWS: 0-5 KTS SST: 27-28 CELSIUS OUTFLOW: MODERATE RADIAL 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 18S IS FORECAST TO CONTINUE ON A WESTWARD TRACK UNTIL TAU 24 AS IT TRACKS ALONG THE NORTHERN PERIPHERY OF THE STR TO THE SOUTH. AFTER TAU 24, THE SYSTEM IS FORECAST TO BEGIN A SOUTHWESTWARD TRACK AS IT STARTS TO ROUND THE NORTHWESTERN PERIPHERY OF THE STR. THE SYSTEM IS EXPECTED TO CONTINUE THE SOUTHWESTWARD TRACK THROUGH THE REMAINDER OF THE FORECAST INTERVAL. REGARDING THE JTWC INTENSITY FORECAST, TC 18S IS FORECAST TO INTENSIFY TO A PEAK OF 95 KTS AROUND TAU 12 AND MAINTAIN THAT INTENSITY THROUGH TAU 24 DUE PRIMARILY TO AN INCREASE IN OUTFLOW ALOFT AND THE PERSISTENCE OF LOW VWS. AFTER TAU 24, VWS VALUES BEGIN TO RISE TO AROUND 15 KTS AND THE SYSTEM IS EXPECTED TO START DEGRADING. TC 18S IS, AS A RESULT, FORECAST TO BE 90 KTS NEAR TAU 36 AND 85 KTS NEAR TAU 48. AFTER TAU 48, DRY AIR BEGINS TO ENTRAIN INTO THE SYSTEM AND VWS IS EXPECTED TO INCREASE TO 25-30 KTS DUE TO PROXIMITY TO THE UPPER-LEVEL JET WHICH WILL AID TO QUICKLY WEAKEN THE SYSTEM. TC 18S IS FORECAST TO WEAKEN TO 60 KTS NEAR TAU 72 AND EVENTUALLY DISSIPATE TO 30 KTS BY TAU 96. MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT THROUGH TAU 72 WITH A 250 NM CROSS-TRACK SPREAD AT TAU 72. GUIDANCE BEGINS TO SPREAD AFTERWARDS AND THE CROSS-TRACK SPREAD INCREASES TO 350 NM AT TAU 96 AS THE MODELS VARY ON THE SHARPNESS OF THE TURN AROUND THE STR. THEREFORE, THE JTWC TRACK FORECAST IS ASSESSED WITH HIGH CONFIDENCE THROUGH TAU 72 AND MEDIUM CONFIDENCE FOR THE REMAINDER OF THE FORECAST. THE JTWC INTENSITY FORECAST IS ASSESSED WITH OVERALL LOW CONFIDENCE DUE TO TECHNICAL DIFFICULTIES PREVENTING RECENT DATA FROM GFS, HWRF, AND HAFS-A BEING INCORPORATED INTO THE MODEL GUIDANCE FOR THIS WARNING. FORECAST CONFIDENCE: TRACK 0 - 72 HR: HIGH TRACK 72-120 HR: MEDIUM INTENSITY 0 - 72 HR: LOW INTENSITY 72-120 HR: LOW// NNNN
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全球热带气旋监测公报
“纳维尔”向偏西方向移动
时 间：21日14时（北京时）
海 域：澳大利亚附近海域
命 名：“纳维尔”，NEVILLE
中心位置：南纬17.9度、东经105.8度
强度等级：三级强热带气旋
最大风力：12级（35米/秒，相当于我国的台风级）
中心气压：976百帕
参考位置：科科斯群岛东偏南方向约1150公里的洋面上
变化过程：过去24小时，“纳维尔”由8级加强到12级
预报结论：“纳维尔”将以每小时15-20公里的速度向偏西方向移动，强度还将有所增强。
图1 卫星红外监测图像（北京时间2024年03月21日14时00分）
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