HAMISH

History

Tropical Cyclone Hamish was a short-lived and weak system that formed late in the 1998–99 Australian region season, spending its entire life over the open waters of the Indian Ocean.

The cyclone developed on 20 April 1999 within an active monsoon trough in the far western part of the Australian region of responsibility, roughly 1,000 km northwest of the Cocos (Keeling) Islands. Tracking generally south-southwestward, the system organised quickly and was assessed as having reached Category 1 strength on the Australian scale that same day. At its peak, Hamish had an estimated minimum central pressure near 993 hPa, with maximum ten-minute mean winds of about 75 km/h and gusts to roughly 95 km/h.

Its period of favourable conditions proved extremely brief. Not long after attaining cyclone intensity, strengthening upper-level westerly shear and an intrusion of drier air separated the deep convection from the low-level circulation. Hamish was downgraded to a tropical low on 21 April, the same day it passed westward into the area monitored by La Réunion, and dissipated over open water.

Because the system remained thousands of kilometres from the Western Australian coast and away from inhabited islands, there were no impacts on land, no damage and no casualties. Warnings were confined to high-seas shipping across the central Indian Ocean, and North West Shelf oil and gas facilities were unaffected.

Sources: Bureau of Meteorology report Wikipedia