Summary
Tropical Cyclone Olga had two phases at tropical cyclone intensity, firstly in the Coral Sea and then in the Gulf of Carpentaria crossing the Queensland Gulf coast at category 1 intensity.
A tropical low was initially analysed in the Pacific Ocean to the northeast of the Solomon Islands on 19 January. The low then moved quickly in a southwesterly direction into the Coral Sea before it developed overnight from 22-23 January into a tropical cyclone. While tracking across the Coral Sea Olga interacted with Ex-Tropical Cyclone Neville in a manner referred to as the Fujiwhara Effect, whereby two low pressure systems can influence each other to the extent that they can tend to orbit each other like two planets. At their closest point the two systems came within less than 300km of each other late on 23 January.
Olga then intensified further later on 23 January into a category 2 system as it approached the Queensland east coast. Olga weakened to cross the coast as a tropical low about 80 km south of Cairns early on 25 January then tracked westwards across inland Queensland and into the Northern Territory.
The system then found itself under the influence of an upper trough crossing southeastern Australia by 29 January, which then steered the system in an easterly direction over southern Gulf of Carpentaria waters. Once the system moved over the warm waters of the Gulf, Olga re-intensified into a tropical cyclone.
Olga made landfall about the Gulf Country coast for the final time early on 30 January as a category 1 system. The system then continued to move in a southerly direction across inland Queensland while also delivering widespread rain to much of the state. Cumulative rainfall totals exceeded 200 mm over a wide swathe of northern Queensland and exceeding 400 mm near the southern Gulf of Carpentaria of Northern Territory and Queensland.
Track and Intensity(Time in AEST (UTC+10h))
Weekly rainfall ending 1 February 2010
