The seventh and last tropical cyclone to affect the Eastern region in the 1984-85 season was Tanya . The cyclone developed from a low which formed on the ITCZ about 700 km southeast of Port Moresby during 27 March 1985. This low drifted firstly north-westwards and then west-southwestwards until cyclonic intensity was reached at 0600 UTC 29 March at 13.4°S, 149.3°E. The central pressure of Tanya was then 995 hPa. The west-southwesterly track continued for a further twelve hours before the cyclone took on a westerly track while continuing to deepen. Maximum intensity was reached at 1800 UTC 30 March when Tanya had a central pressure of 982 hPa and an estimated maximum wind speed of 100 km/h.
The near westerly track was maintained for another twelve hours during which time the system decayed marginally. The track then became south- westerly and this was maintained until landfall at about 0400 UTC on 1 April in Princess Charlotte Bay. Cyclonic intensity was lost within an hour or two. The resulting low continued southwestwards to the centre of Cape York Peninsula before losing its identity.
Tropical cyclone Tanya caused only limited damage to vegetation and no structural damage was reported. The maximum reported wind speed was 93 km/h at 0600 UTC 30 March from a ship.