Weather Warning

Tropical Cyclone Technical Bulletin: AUSTRALIA - Western Australia Issued by Australian Government Bureau of Meteorology TROPICAL CYCLONE WARNING CENTRE at: 1854 UTC 26/12/2025 Name: Tropical Cyclone Grant Identifier: 03U Data At: 1800 UTC Latitude: 11.8S Longitude: 90.8E Location Accuracy: within 20nm (35 km) Movement Towards: west (273 deg) Speed of Movement: 9 knots (16 km/h) Maximum 10-Minute Wind: 55 knots (100 km/h) Maximum 3-Second Wind Gust: 75 knots (140 km/h) Central Pressure: 989 hPa Radius of 34-knot winds NE quadrant: 30 nm (55 km) Radius of 34-knot winds SE quadrant: 30 nm (55 km) Radius of 34-knot winds SW quadrant: 40 nm (75 km) Radius of 34-knot winds NW quadrant: 40 nm (75 km) Radius of 48-knot winds NE quadrant: 15 nm (30 km) 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: 15 nm (30 km) Radius of 64-knot winds: Radius of Maximum Winds: 10 nm (20 km) Dvorak Intensity Code: T3.5/3.5/D0.5/24HRS STT:D0.5/06HRS Pressure of outermost isobar: 1008 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: 27/0000: 11.9S 89.9E: 030 (060): 055 (100): 989 +12: 27/0600: 12.0S 89.1E: 040 (080): 055 (100): 988 +18: 27/1200: 12.0S 88.3E: 050 (095): 060 (110): 985 +24: 27/1800: 12.2S 87.4E: 055 (100): 060 (110): 985 +36: 28/0600: 12.7S 85.4E: 060 (110): 060 (110): 986 +48: 28/1800: None None: None (None): None (None): None +60: 29/0600: None None: None (None): None (None): None +72: 29/1800: None None: None (None): None (None): None +96: 30/1800: None None: None (None): None (None): None +120: 31/1800: None None: None (None): None (None): None REMARKS: Tropical Cyclone Grant continues to move westwards and maintain deep convection near and to the west of its centre. Position, intensity and structure is based on a 1208 UTC SAR pass. TC Grant is a very small system and the inner core doesn't appear to be impacted by environmental shear and surrounding dry air. Dvorak analysis: DT=3.0 based on shear pattern, although this is likely to be an underestimate given the small size of Grant. MET=3.5 based on 24h D- trend, PAT=3.5. FT and CI 3.5. Objective guidance estimates (1-min mean) at 1715 UTC: ADT 53 kn, AiDT 56 kn, DPRINT 39 kn, DMINT (1310 UTC) 50 kn, SATCON (1420 UTC) 51 kn. A 1209 UTC SAR pass showed Grant was a small and relatively symmetrical system. Intensity estimated at 55 knots. Dry air appears to be wrapping around the north of Grant, and although convection has increased near the centre, it is almost absent from the eastern side, an effect of moderate ENE shear. This shear has been decreasing, and may decrease a little further in the next 24-48 hours. The forecast is for very gradual intensification of Grant in the short term, noting that as a very small system Grant may react quickly to any changes in environmental conditions. As Grant is moving into the La Reunion Area of Responsibility at around 0000 UTC on Saturday, the forecast doesn't extend beyond 42 hours, however further intensification is likely as Grant continues to move west southwest through favourable environmental conditions in the central Indian Ocean. Copyright Commonwealth of Australia == The next bulletin for this system will be issued by: 27/0130 UTC.