From Weather Alert@21:1/175 to All on Sun Feb 28 03:28:00 2021
AXAU01 APRF 271831
IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE
at: 1831 UTC 27/02/2021
Name: Tropical Cyclone Marian
Identifier: 15U
Data At: 1800 UTC
Latitude: 16.4S
Longitude: 92.6E
Location Accuracy: within 20 nm [35 km]
Movement Towards: southwest [233 deg]
Speed of Movement: 9 knots [17 km/h]
Maximum 10-Minute Wind: 60 knots [110 km/h]
Maximum 3-Second Wind Gust: 85 knots [155 km/h]
Central Pressure: 976 hPa
Radius of 34-knot winds NE quadrant: 120 nm [220 km]
Radius of 34-knot winds SE quadrant: 100 nm [185 km]
Radius of 34-knot winds SW quadrant: 130 nm [240 km]
Radius of 34-knot winds NW quadrant: 120 nm [220 km]
Radius of 48-knot winds NE quadrant: 40 nm [75 km]
Radius of 48-knot winds SE quadrant: 40 nm [75 km]
Radius of 48-knot winds SW quadrant: 50 nm [95 km]
Radius of 48-knot winds NW quadrant: 50 nm [95 km]
Radius of 64-knot winds:
Radius of Maximum Winds: 30 nm [55 km]
Dvorak Intensity Code: T4.0/4.0/D0.5/24HRS STT:S0.0/06HRS
Pressure of outermost isobar: 1004 hPa
Radius of outermost closed isobar: 300 nm [555 km]
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+06: 28/0000: 16.8S 92.1E: 035 [065]: 060 [110]: 975
+12: 28/0600: 17.1S 91.6E: 045 [080]: 065 [120]: 973
+18: 28/1200: 17.4S 91.2E: 050 [090]: 070 [130]: 971
+24: 28/1800: 17.6S 90.7E: 050 [095]: 070 [130]: 971
+36: 01/0600: 18.0S 90.0E: 055 [105]: 075 [140]: 967
+48: 01/1800: 18.3S 89.6E: 070 [130]: 075 [140]: 962
+60: 02/0600: 18.4S 89.8E: 085 [155]: 070 [130]: 967
+72: 02/1800: 18.6S 90.7E: 100 [185]: 065 [120]: 973
+96: 03/1800: 19.7S 93.4E: 135 [255]: 055 [100]: 981
+120: 04/1800: 21.4S 95.8E: 180 [335]: 050 [095]: 983
REMARKS:
Position analysis is difficult due to a lack of recent microwave imagery and what looks like a ragged eye appearring in recent EIR images likely to be well displaced from the LLCC. A scat pass at 15UTC is consistent with current track.
DVK embd centre and MET keep FT at 4.0 so intensity estimate remains steady at 60 knots [10-min]. This is consistent with the SATCON estimate at 1251 UTC of 68 kts 1-min [ADT indicating 57 knots with AMSU estimate 80 knots] and recent scat passes showing 50-55 knots.
The system continues to lie under easterly shear [CIMSS analysed shear at 27/1200 UTC was 24 knots from the east] though this shear appears to be in the upper levels [above 400hPa]. The shear is expected to persist in the short term,
reducing in 12-24 hours as the system approaches 090E and the steady SW motion slows. The system is likely to be slow moving for a period on Monday before taking a track to the southeast on Tuesday.
A strengthening trend is forecast but is slightly less than normal due to the environment and large size. SHIPS guidance indicates rapid intensification is unlikely which is consistent with the synoptic environment.
SST's are cooler to the south, with sub 26 degrees south of about 18S. This could limit development from Monday and then assist in the system weakening as it moves further south. The circulation is expected to remain at TC strength over open waters for the next 5-7 days.
Copyright Commonwealth of Australia
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The next bulletin for this system will be issued by: 28/0130 UTC.
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