Severe Tropical Cyclone Kerry

13 February - 6 March 1979


Kerry was a remarkable tropical cyclone having a long life-span and erratic track. It is also notorious for being only one of two cyclones in the Australian region to have an airplane (a US NOAA research aircraft) fly into the cyclone (the other being TC Rosa ). Indeed a wind speed of 252 km/h measured by this aircraft at an altitude of 540 m was at that time one of the strongest low-level winds measured in a cyclone in the Australian area.

Kerry 's origin is linked to a low that became evident near 5°S, 170°E on 7 February 1979. By 10 February 1979 some cyclonic curvature could be detected in the surrounding convective cloud field. Three days later the system was displaying consistent organisation. The subsequent erratic track is shown below.

Kerry intensified steadily while moving west-southwest at 15 to 35 km/h and by 15 February 1979 was classified as a severe tropical cyclone. As Kerry crossed the Solomon Islands maximum observed winds were 72 km/h at about 70 km south of the cyclone, however widespread destruction and loss of life were experienced near the centre, indicating the existence of much stronger winds.. Estimated winds from satellite data were 125 to 145 km/h.

After moving away from the Solomon Islands on a southwesterly track, Kerry again intensified steadily. Maximum intensity was attained on 19 February 1979 and Kerry then slowly weakened while moving towards landfall on 1 March 1979. Kerry moved erratically around a large loop from 19 to 26 February 1979 crossing its own track at least three times.

A factor in the decay after 19 February was the intrusion of dry sub-tropical air that moved around the west and northwest of the cyclone. This is a common feature of decaying cyclones in the Australian region. Aircraft reconnaissance flights on 21 and 22 February 1979 and satellite imagery together show evidence of this dry air and suppressed convection in these quadrants.

As Kerry approached the coast across the Whitsunday Islands radar surveillance showed a weak vortex with a ragged and poorly defined eye, but winds of over 108 km/h were observed.

Kerry moved west-northwest over land for just over a day then moved northward back over the Coral Sea. The cyclone began to re-intensify east of Townsville late on 2 March 1979. This re-intensification continued while the cyclone moved northward to be east of Cairns on 3 March. Later that day Kerry came under the influence of strong northwesterly winds ahead of an appraoching large amplitude upper-level trough and accelerated to the southeast, weakened and decayed over the ocean on 6 March 1979.

Although Kerry was a severe cyclone while well offshore, it had weakened considerably by the time it made landfall and only minor wind damage occurred in some coastal centres and offshore resorts.

Nevertheless, boats collectively worth hundreds of thousands of dollars were damaged or destroyed in Mackay harbour on 1 March 1979. Twenty-four hour rainfall totals of up to 250 mm were reported from mainland centres with an isolated fall of 402 mm from Hayman Island in the Whitsunday Group . Little flood damage resulted however.

Track and intensity

Best Track of Severe Tropical Cyclone Kerry