Early in April there was a persistent low with associated convective activity northwest of Cocos Island. This low slowly moved southwest and deepened, attaining cyclone intensity on 7 April. The storm continued deepening and reached peak intensity three days later when a clear eye could be seen on satellite imagery. At that time the central pressure was estimated at 940 hPa with maximum winds of about 180 km/h.
During 10 and 11 April, Olga moved steadily south-southwest. This movement was probably influenced by a very intense low that was operating in the Amsterdam-Kerguelen Island area near longitude 80°E.
The influence of this low continued as it moved eastwards. On the 13th Olga accelerated to the east-southeast as it came under the influence of strong northwesterly winds ahead of the southern depression. Most of the cloud sheared from the storm's centre and it had become extra-tropical by 14 April. The system finally dissipated on the 18th after moving erratically off the Western Australian coast.
The highest reported wind was north-northwest at 70 km/h at 1800 UTC on the 12th by a ship 220 km northeast of the centre. The closest land station to the cyclone was Cocos Island which recorded easterly winds up to 56 km/h during 7 April, and a pressure of 1004 hPa when Olga was located about 620 km northwest of the island. No damage or loss of life was reported.