簽到天數: 868 天 [LV.10]以壇為家III
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jrchang5|2019-3-24 11:43
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BoM 24/00Z、03Z定強為澳式C3上限，近中心最大風速為85kts(155km/h)。
依最新的雷達降水回波圖所示，風眼眼牆已抵達西澳西北部海岸，中心即將登陸。
IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0054 UTC 24/03/2019
Name: Severe Tropical Cyclone Veronica
Identifier: 19U
Data At: 0000 UTC
Latitude: 20.3S
Longitude: 117.7E
Location Accuracy: within 15 nm [30 km]
Movement Towards: south southeast [160 deg]
Speed of Movement: 5 knots [10 km/h]
Maximum 10-Minute Wind: 85 knots [155 km/h]
Maximum 3-Second Wind Gust: 120 knots [220 km/h]
Central Pressure: 952 hPa
Radius of 34-knot winds NE quadrant: 110 nm [205 km]
Radius of 34-knot winds SE quadrant: 80 nm [150 km]
Radius of 34-knot winds SW quadrant: 90 nm [165 km]
Radius of 34-knot winds NW quadrant: 100 nm [185 km]
Radius of 48-knot winds NE quadrant: 65 nm [120 km]
Radius of 48-knot winds SE quadrant: 55 nm [100 km]
Radius of 48-knot winds SW quadrant: 65 nm [120 km]
Radius of 48-knot winds NW quadrant: 65 nm [120 km]
Radius of 64-knot winds: 35 nm
Radius of Maximum Winds: 25 nm [45 km]
Dvorak Intensity Code: T5.0/5.0/S0.0/24HRS STT:S0.0/06HRS
Pressure of outermost isobar: 1000 hPa
Radius of outermost closed isobar: 140 nm [260 km]
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+06: 24/0600: 20.7S 117.8E: 025 [050]: 085 [155]: 950
+12: 24/1200: 20.9S 117.9E: 040 [070]: 075 [140]: 958
+18: 24/1800: 21.0S 117.8E: 050 [095]: 055 [100]: 970
+24: 25/0000: 21.0S 117.7E: 065 [120]: 050 [095]: 980
+36: 25/1200: 21.0S 117.2E: 085 [155]: 035 [065]: 992
+48: 26/0000: 21.2S 115.9E: 105 [190]: 030 [055]: 997
+60: 26/1200: : : :
+72: 27/0000: : : :
+96: 28/0000: : : :
+120: 29/0000: : : :
REMARKS:
Severe TC Veronica has maintained a high-end category 3 status over the past 6
to 8 hours. The strongest convection overnight was persistently in the
southwest quadrant, though convection has increased in the southeast and
southern flanks of the system in the last 3 hours. Veronica continues to display
a large eye [40nm in diameter], which has generally been somewhat irregular
and/or ragged with smaller scale vortices embeded in the eyewall/eye interface.
This has recently led to the appearance of some irregular motion. The eye is
readily evident on satelltie and radar imagery, giving high confidence in the
location of the system centre.
Dvorak analysis has been between 4.5 and 5.0 in the last 6 hours based on an eye
pattern. Adjusted MET is 5.0. FT is 5.0 and CI is 5.0, with intensity set at 85
knots. CIMSS ADT CI is around 5.7, NESDIS ADT CI has risen to 6.2 with a return
to EYE pattern. SATCON at 2220UTC was 110 knots [1-minute winds].
Conditions remain somewhat conducive to develoment for the next 12 hours while
the system remains over water. Wind shear is presently northwesterly around 15
knots. Strong poleward outflow persists in the upper levels, with no equatorward
outflow visible. SSTs in the vicinity are over 30C. Dry air to the north is
slowly encroaching on the eastern flank of the system, but does not appear to be
infiltrating into the core region at present. Wind shear should increase over
the system as it tracks further south which should see the dry air further
ingested, contributing to a weakening trend.
The combination of a broad mid-latitude upper trough to the south and a
mid-level ridge to the east is expected to steer the system towards the south
southeast over the next 12 hours. Recent motion of the system has been somewhat
irregular as these steering features are currently very weak. Landfall is still
anticipated later today, but due to the slow moving nature of Veronica, the eye
and most significant impacts from the system may persist for 12 to 24 hours near
the coast. The movement over land later on Sunday and early next week varies
considerably in the guidance, but a westwards track close to the coast seems the
most likely as the system weakens due to a strengthening mid-level ridge over
Western Australia. It is unlikely to remain a tropical cyclone after Monday,
even if it moves back over water, as the environment becomes very unfavourable.
High tides will be close to the highest astronomical tide exacerbating the risk
of a significant storm tide impact, and Port Hedland has already recorded a
storm tide about 1m above HAT at midnight. The slow motion also means that
rainfall totals will be higher than for normal cyclone rainfall amounts and
cumulative totals in excess of 500mm are possible.
Copyright Commonwealth of Australia
==
The next bulletin for this system will be issued by: 24/0730 UTC by Perth TCWC. IDW24100
Australian Government Bureau of Meteorology
Western Australia
Tropical Cyclone Warning Centre
Media: Transmitters serving the area between Pardoo and Dampier, including Port Hedland, are requested to USE the Standard Emergency Warning Signal before broadcasting the following warning.
TOP PRIORITY FOR IMMEDIATE BROADCAST
TROPICAL CYCLONE ADVICE NUMBER 46
Issued at 11:10 am WST on Sunday 24 March 2019
Headline:
Severe Tropical Cyclone Veronica is causing DESTRUCTIVE winds and heavy rainfall on the central Pilbara coast between Dampier and Port Hedland.
Areas Affected:
Warning Zone
Wallal to Mardie, including Port Hedland and Karratha, and adjacent inland areas, including Pannawonica
Watch Zone
None
Cancelled Zone
None.
Details of Severe Tropical Cyclone Veronica at 11:00 am AWST:
Intensity: Category 3, sustained winds near the centre of 155 kilometres per hour with wind gusts to 220 kilometres per hour.
Location: within 30 kilometres of 20.3 degrees South 117.7 degrees East, estimated to be 90 kilometres west of Port Hedland and 100 kilometres east northeast of Karratha.
Movement: south southeast at 6 kilometres per hour.
The cyclone's core has reached land and is over the coast just east of Roebourne and west of Port Hedland. The centre is forecast to remain near the coast today and tonight. Veronica is forecast weaken during Monday and start moving to the west.
Hazards:
VERY DESTRUCTIVE WINDS with gusts in excess of 165 kilometres per hour are expected near the cyclone centre today and tonight. This includes Roebourne, Wickham and Point Samson.
DESTRUCTIVE WINDS with gusts exceeding 125 kilometres per hour are occurring along the Pilbara coast between Dampier and Port Hedland and are forecast to extend to adjacent inland areas today.
GALES with gusts to 100 kilometres per hour are expected between remaining parts between Mardie and Pardoo, and may extend to adjacent inland areas including Pannawonica later today. They may also extend east of Wallal Downs tonight if the system moves further east.
The slow movement of the cyclone means that communities in the path of the cyclone should prepare to shelter from the destructive winds for an extended period today and into tomorrow.
Widespread very heavy rainfall conducive to MAJOR FLOODING is likely over the Pilbara coast and adjacent inland areas today and Monday. Heavy rainfall is expected to result in significant river rises, areas of flooding and hazardous road conditions. Some roads may become impassable and some communities may become isolated. Flood Warnings and Watches are current, please refer to http://www.bom.gov.au/wa/warnings/ for further details.
People along the Pilbara coast east of Wickham are warned of the potential for a VERY DANGEROUS STORM TIDE on the high tide today (high tide at 1pm at Port Hedland) and tonight (high tide at 1:30am Monday at Port Hedland). Tides are likely to rise significantly above the normal high tide mark with DAMAGING WAVES and VERY DANGEROUS COASTAL INUNDATION. Tides in remaining areas of the warning area are advised that tides will rise above the normal high tide with some flooding of low-lying coastal areas.
Recommended Action:
DFES advises of the following community alerts:
RED ALERT: People in or near communities between Pardoo and Mardie, including Port Hedland, South Hedland, Whim Creek, Point Samson, Wickham, Roebourne, Karratha, Dampier but excluding Marble Bar, need to go to shelter immediately.
YELLOW ALERT: People in or near remaining communities between Wallal and Pardoo and inland to Marble Bar need to take action and get ready to shelter from a cyclone.
BLUE ALERT: People in or near communities for parts of the inland Pilbara including Pannawonica need to prepare for cyclonic weather and organise an emergency kit including first aid kit, torch, portable radio, spare batteries, food and water.
ALL CLEAR: People in Nullagine are advised that there is no longer the risk of gales
Next Advice:
The next advice will be issued by 12:00 pm AWST Sunday 24 March.
Cyclone advices and DFES Alerts are available by dialling 13 DFES (13 3337) 
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