Summary
Tropical Cyclone Winsome was initially analysed as a large circulation over the Arafura Sea north of Australia on 8 February, in an active monsoon trough. The system was in a region of low vertical shear, and the upper pattern was favourable for development, with strong cross-equatorial easterlies, and a vigorous upper trough leaning back from the Coral Sea to an upper low at the base of the Gulf of Carpentaria, providing an area of good upper divergence. In addition, a westward-propagating equatorial Rossby wave interacted with the monsoon low as the low slowly drifted into in the Gulf of Carpentaria.
Winsome became a tropical cyclone on the 10th. It moved south-southwest, crossing the coast of the Northern Territory within 24 hours. Even while still a monsoon low, Winsome was associated with a broad area of gales in the Gulf of Carpentaria. These winds produced higher seas and increased water levels in the trapped basin of the Gulf. The cyclone's lifetime corresponded with peak spring tides, and the coastal crossing in the Gulf occurred near the high tide. A 2 metre storm surge caused damage estimated at A$1 million in the coastal community of Numbulwar, and the settlements of Bing Bong, Alyangula and Nhulunbuy were also affected by flooding from storm surges. Winsome caused one death: a fisherman was lost from his vessel south of Groote Eylandt at the mouth of the Roper River.
Winsome moved inland, but remained a significant system as it crossed northern Australia during the next few days. Gale-force monsoon westerlies persisted at a large radius from the centre to the north. Darwin experienced strong winds and severe wind gusts, as ex- Winsome moved 300 km to the south on 12 and 13 February. Large swell combined with high tides to produce coastal erosion and dangerous conditions at Darwin beaches. Heavy rain associated with the low caused extensive flooding in many parts of the Northern Territory, cutting major highways.
Track and intensity
All times in UTC - add 9.5 hours to convert to CST.
