ISOBEL
1984-85 season · AU198485_08U
History
Severe Tropical Cyclone Isobel developed in the South-East Indian Ocean during February 1985, originating from a tropical low that formed rapidly on 11 February south of the western tip of Java. The system organised quickly, reaching tropical cyclone intensity within roughly 36 hours of development. Isobel initially tracked southeast before turning onto a south-westerly course deeper into the Indian Ocean basin.
The cyclone reached its peak intensity between 14 and 16 February, achieving Category 3 status on the Australian scale with 10-minute sustained winds of 140 km/h and a minimum central pressure of 960 hPa. Its early development was influenced by the nearby presence of Cyclone Hubert, which was active to its east-southeast within the same monsoon trough at the time.
As Isobel continued moving southwest into progressively cooler waters, it gradually weakened and dissipated over the open ocean on 22 February 1985. The system remained entirely at sea throughout its lifetime, tracking well away from the Western Australian coastline. It made no landfall, caused no structural damage, and resulted in no casualties or injuries. Isobel is notable primarily as an intense, compact open-ocean system that, despite reaching severe tropical cyclone strength, posed no threat to populated areas.
Sources: Bureau of Meteorology report Wikipedia
View full track data (44 observations)
| Date/Time (UTC) | Category | Position | Pressure | Wind |
|---|---|---|---|---|
| 1985-02-11 06:00:00 | 1 | -7.6, 100.6 | 1003 hPa | 10 km/h |
| 1985-02-11 12:00:00 | 1 | -7.9, 100.8 | 1003 hPa | 10 km/h |
| 1985-02-11 18:00:00 | 1 | -8.3, 101.1 | 1003 hPa | 13 km/h |
| 1985-02-12 00:00:00 | 1 | -8.7, 101.5 | 1002 hPa | 13 km/h |
| 1985-02-12 06:00:00 | 1 | -9.1, 101.7 | 1001 hPa | 13 km/h |
| 1985-02-12 12:00:00 | 1 | -9.6, 101.9 | 1000 hPa | 13 km/h |
| 1985-02-12 18:00:00 | 1 | -10.2, 102.2 | 997 hPa | 15 km/h |
| 1985-02-13 00:00:00 | 1 | -10.8, 102.4 | 994 hPa | 15 km/h |
| 1985-02-13 06:00:00 | 1 | -11.5, 102.5 | 992 hPa | 15 km/h |
| 1985-02-13 12:00:00 | 1 | -12.0, 102.0 | 988 hPa | 21 km/h |
| 1985-02-13 18:00:00 | 1 | -12.4, 101.1 | 986 hPa | 23 km/h |
| 1985-02-14 00:00:00 | 1 | -12.8, 100.6 | 982 hPa | 26 km/h |
| 1985-02-14 06:00:00 | 1 | -13.4, 100.4 | 976 hPa | 28 km/h |
| 1985-02-14 12:00:00 | 1 | -13.6, 101.4 | 977 hPa | 28 km/h |
| 1985-02-14 18:00:00 | 1 | -13.0, 101.4 | 980 hPa | 28 km/h |
| 1985-02-15 00:00:00 | 1 | -12.7, 102.0 | 982 hPa | 28 km/h |
| 1985-02-15 06:00:00 | 1 | -12.6, 102.7 | 982 hPa | 26 km/h |
| 1985-02-15 12:00:00 | 1 | -12.8, 103.3 | 981 hPa | 26 km/h |
| 1985-02-15 18:00:00 | 1 | -13.2, 104.0 | 979 hPa | 26 km/h |
| 1985-02-16 00:00:00 | 1 | -13.8, 104.6 | 977 hPa | 26 km/h |
| 1985-02-16 06:00:00 | 1 | -14.4, 105.2 | 973 hPa | 31 km/h |
| 1985-02-16 12:00:00 | 1 | -14.8, 105.5 | 970 hPa | 31 km/h |
| 1985-02-16 18:00:00 | 1 | -15.2, 105.4 | 966 hPa | 33 km/h |
| 1985-02-17 00:00:00 | 1 | -15.6, 105.0 | 960 hPa | 39 km/h |
| 1985-02-17 06:00:00 | 1 | -16.1, 104.5 | 963 hPa | 36 km/h |
| 1985-02-17 12:00:00 | 1 | -16.7, 103.9 | 964 hPa | 36 km/h |
| 1985-02-17 18:00:00 | 1 | -17.1, 103.3 | 966 hPa | 33 km/h |
| 1985-02-18 00:00:00 | 1 | -17.4, 102.7 | 966 hPa | 33 km/h |
| 1985-02-18 06:00:00 | 1 | -17.7, 102.1 | 966 hPa | 33 km/h |
| 1985-02-18 12:00:00 | 1 | -18.1, 101.6 | 966 hPa | 33 km/h |
| 1985-02-18 18:00:00 | 1 | -18.5, 101.2 | 970 hPa | 31 km/h |
| 1985-02-19 00:00:00 | 1 | -19.0, 101.0 | 976 hPa | 26 km/h |
| 1985-02-19 06:00:00 | 1 | -19.6, 100.5 | 976 hPa | 26 km/h |
| 1985-02-19 12:00:00 | 1 | -20.0, 100.1 | 976 hPa | 23 km/h |
| 1985-02-19 18:00:00 | 1 | -20.4, 99.5 | 980 hPa | 21 km/h |
| 1985-02-20 00:00:00 | 1 | -20.9, 98.7 | 984 hPa | 21 km/h |
| 1985-02-20 06:00:00 | 1 | -21.7, 97.7 | 986 hPa | 21 km/h |
| 1985-02-20 12:00:00 | 1 | -22.5, 96.8 | 988 hPa | 18 km/h |
| 1985-02-20 18:00:00 | 1 | -23.4, 96.1 | 990 hPa | 15 km/h |
| 1985-02-21 00:00:00 | 1 | -24.6, 95.5 | 994 hPa | 15 km/h |
| 1985-02-21 06:00:00 | 1 | -26.0, 95.0 | 995 hPa | 15 km/h |
| 1985-02-21 12:00:00 | 1 | -27.7, 94.7 | 998 hPa | 13 km/h |
| 1985-02-21 18:00:00 | 1 | -29.6, 94.4 | 999 hPa | 13 km/h |
| 1985-02-22 00:00:00 | 1 | -31.5, 94.2 | 1002 hPa | 13 km/h |