AXAU21 ABRF 071905 IDQ20018 TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - EASTERN REGION Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE at: 1904 UTC 07/02/2024 Name: Tropical Low Identifier: 06U Data At: 1800 UTC Latitude: 15.6S Longitude: 160.2E Location Accuracy: within 40nm (75 km) Movement Towards: east northeast (066 deg) Speed of Movement: 4 knots (7 km/h) Maximum 10-Minute Wind: 30 knots (55 km/h) Maximum 3-Second Wind Gust: 45 knots (85 km/h) Central Pressure: 997 hPa Radius of 34-knot winds NE quadrant: Radius of 34-knot winds SE quadrant: Radius of 34-knot winds SW quadrant: Radius of 34-knot winds NW quadrant: 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: T2.0/2.0/D0.5/24HRS STT:S0.0/06HRS Pressure of outermost isobar: 1002 hPa Radius of outermost closed isobar: 240 nm (445 km) FORECAST DATA Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure (UTC) : degrees : nm (km): knots(km/h): hPa +06: 08/0000: 15.6S 161.0E: 055 (100): 030 (055): 999 +12: 08/0600: 15.8S 161.9E: 065 (120): 030 (055): 999 +18: 08/1200: 16.1S 162.7E: 070 (130): 030 (055): 999 +24: 08/1800: 16.6S 163.3E: 075 (140): 035 (065): 997 +36: 09/0600: 17.4S 164.3E: 085 (155): 040 (075): 993 +48: 09/1800: 18.2S 165.5E: 105 (195): 050 (095): 986 +60: 10/0600: 18.8S 166.9E: 140 (260): 050 (095): 982 +72: 10/1800: 19.2S 168.1E: 165 (305): 045 (085): 988 +96: 11/1800: 19.3S 169.7E: 210 (395): 035 (065): 994 +120: 12/1800: 19.2S 169.4E: 285 (525): 030 (055): 998 REMARKS: Tropical Low 06U is struggling to develop under the influence of moderate shear. The low has been located using animated IR imagery and an AMSR2 pass from 1503UTC. There is moderate to poor confidence in the position, with the low level centre poorly defined on microwave. Curved banding has been analysed with a wrap of about 0.4, however the curvature is not tightly wrapped around the centre but instead orientates along a trough to the north. A shear pattern would have yielded a high DT at 1800UTC, but since then the convection has become more separated and so may give a more reasonable value going forward. DT is 2.5 based on curved band, with MET and PAT at 2.0. FT/CI held at 2.0 based on MET/PAT. There is currently no objective intensity guidance available. Current intensity is set at 30 knots based on the AMSR2 wind analysis at 1503UTC. The environment is moderately favourable for development with 06U located over warm SSTs with good upper divergence. However, recent shear diagnostics show stronger NW shear developing over the system, which is consistent with appearance on satellite. Another limiting factor seems to have been the very dry air surrounding the system, coupled with strong middle level westerlies just to the north of the centre. Models indicate some development is possible in the next 24 to 48 hours as an upper trough to the southwest increases outflow aloft, however this could be countered by dry air entrainment that may come from the mid-level westerlies and any continuing shear influences. This window for development may be short lived as from Saturday models are broadly consistent with upper winds increasing and the effects of dry air becoming more pronounced. Steering is being governed by the mid-level westerlies to the north of the low and movement is forecast to be slowly to the east for the next 24 hours. A very weak mid-level low to the south intensifies to the southwest of 06U during Friday and the system begins to move more southeast under this influence. Movement is then expected to be slow as the system weakens. From next Monday or Tuesday the shallow remnant low will most likely steer towards the west northwest due to a low level ridge to the south. Copyright Commonwealth of Australia == There will be no further bulletins issued by the Australian Bureau of Meteorology for this system unless it moves back into the Australian Area of Responsibility.