ALISON

History

Severe Tropical Cyclone Alison–Krisostoma was an oceanic cross-basin storm that was active during the 1985–86 Australian region cyclone season. The system originated as a tropical low over the Indian Ocean southwest of Sumatra on 4 April 1986, and was steered on a steady west-southwestward track by a strong atmospheric ridge to its south. It organised sufficiently to be named Alison by the Bureau of Meteorology on 7 April, when it attained gale-force winds. During its westward passage, the storm's outer bands brushed the Cocos Islands on 8 April, with the island's weather station briefly recording gale-force conditions.

On 10 April, the system crossed the 90°E meridian and exited the Australian area of meteorological responsibility, at which point the Mauritius Meteorological Service assumed responsibility and renamed it Krisostoma. The storm reached a peak intensity equivalent to a Category 3 system on the Australian scale, with estimated one-minute sustained winds of around 160 km/h and a minimum central pressure of approximately 974 hPa. An approaching low-pressure system subsequently turned the storm toward the southeast; it re-entered the Australian basin in a weakened state before fully dissipating on 14 April 1986. The cyclone remained over open ocean throughout its lifetime and caused no structural damage or casualties on land.

Sources: Bureau of Meteorology report Wikipedia