Summary
Tropical cyclone Annette was a large cyclone which formed in the southeast Indian Ocean about the same time as Vania and tracked southeastwards across the Australian continent. A low to mid-level cyclonic circulation was first analysed over Java on 9 December and moved south to be near 12°S, 116°E by 12 November. The low remained almost stationary for two days as weak vertical wind shear and strong cross-equatorial monsoonal flow below 700 hPa contributed to a favourable development environment.
Tropical cyclone Annette was named early on 15 December and rapidly intensified to hurricane intensity the next day under the influence of a mid to high-level trough passing to the south. The cyclone moved eastward and reached maximum intensity with estimated mean winds of 55 m/s (estimated central pressure 925 hPa) at 0000 UTC 18 December prior to crossing the West Australian coast. Annette's eye passed over Mandorah Staion about 10 km inland from the coast (240 km east of Port Hedland) at about 0900 UTC 18 December where a minimum MSLP pressure 933 hPa and wind gusts to 60 m/s were recorded. The cyclone caused extensive damage to station and road-house buildings within 30 km of the coast. Five hundred cattle were drowned by the storm surge after being driven towards the sea by the wind.
Annette accelerated southeastward on 19 December as upper-level northwesterly flow strengthened ahead of an approaching trough to the southwest. The cyclone underwent an extratropical transition as it moved over- land and the resultant low pressure system retained gale- force mean winds with gusts to 25 rnls on its eastern side as it moved into the Great Australian Bight early on 20 December.
For more details see the TC Annette Report (pdf)
Track and intensity
All times in WST - subtract 8 hours to convert to UTC.
