Summary
Koji was short-lived as a defined tropical cyclone off the north Queensland coast, but the duration and impact of this weather event over north and western Queensland was extensive.
On 7 January 2026 a tropical low (12U) formed in a monsoon trough in the northern Coral Sea. Initially the low moved slowly westwards until 9 January, when the monsoon and a mid-level ridge to east steered the tropical low towards the south. At this time gales developed on the southeastern side of the low. An increase in monsoon flow to the north, combined with an increase in southeasterly winds to the south of the low resulted in the tropical low's broad structure. Early on 10 January gales began to extend around the centre and at 4pm AEST (0600 UTC) 10 January Tropical Cyclone Koji was named as a category 2 system, with storm force winds occurring at Willis Island (mean 100 kilometres per hour, with a maximum gust 133 kilometres per hour at 12:41pm EST).
As Koji approached the Queensland coast to the south of Townsville, the strongest winds were recorded further to the south at the Whitsunday Islands. A severe wind gust of 117 kilometres per hour was recorded at Hamilton Island at 8:36am, and northeast of the Whitsundays at Hardy Reef at 11am EST 11 January. Just prior to Koji making landfall, the extent of gales reduced below half-way around the centre resulting in the system being downgraded to a tropical low. The system crossed the coast between Ayr and Bowen around 10am AEST 11 January then proceeded to move inland over the following days.
Strong winds brought down trees and branches causing some structural damage and power outages, mostly in the Mackay and Whitsunday region. Some boats broke their moorings and were damaged.
Heavy rainfall was extensive, with several sites in the Pioneer River catchment observing more than 350 mm of rainfall in 24 hours to 9am on 11 January. Heavy rainfall continued 12 January. The highest rainfall was observed at Mt William with 601 mm in the 48 hours to 9am 12 January. Major flooding occurred south of Mackay in the Pioneer catchment. Ex-tropical cyclone Koji could be tracked as it moved inland for several days, enhancing heavy rainfall along its path. As Ex-Koji moved inland moderate to major flooding occurred in basins along the track, all the way to the NT border. The weekly rainfall totals are shown below.
The highest storm tides observed were between 0.5 and 1.0 metres near Bowen and Airlie Beach, but the resulting tides were well below the highest astronomical tides.
Tropical Cyclone Koji was the seventh tropical cyclone in the Australian region for the 2025/26 season.
*Note: A comprehensive report will be issued for this event upon completion of a post event reanalysis. All information relating to intensity and track is preliminary information and subject to change following post analysis.
Track and Intensity
(Times in AEST, UTC+10h)
Weekly rainfall totals
(11-17 January 2026)
