Severe Tropical Cyclone Alison

7 - 13 November 1998


A depression with a clear cloud signature was evident to the northeast of the Cocos Islands from the 7th. There was initially significant vertical shear over the system and it developed only slowly. Tropical cyclone intensity was reached on 8 November when a separate outflow developed over it. Intensification then became more rapid and the cyclone moved off towards the southwest under the influence of north-easterly steering. Vertical shear then began to limit development. On 11 November it moved through a break in the ridge subsequently encountering stronger vertical wind shear and cooler seas, causing it to weaken.

For more details see the TC Alison Report (pdf)

Track and intensity

All times in WST - subtract 8 hours to convert to UTC.

Best Track of Severe Tropical Cyclone Alison