Ex-Tropical Cyclone Owen dumped record rainfall in North Queensland from 15 to 16 December, 2018.

Queensland Police warned that the “significant rainfall has resulted in an increase in water flow in many streams, tributaries and water courses and police are urging everyone to exercise extreme caution.”
Police later reported that a young man had died after being swept away in a flood-affected creek in Mutarnee north of Townsville.
Tropical Cyclone Owen made landfall approximately 70 km south of Kowanyama as acategory 3 tropical cyclone. The cyclone produced sustained winds of 120 kilometres per hour and gusts of 170 kilometres per hour. Owen was later downgraded to a tropical low Saturday afternoon.
Record Rain
Australia’s Bureau of Meteorology (BOM) said in a statement of 16 December:
“Halifax (near Ingham) received 681mm of rain in the 24 hours to 9am this morning (16 December) with 122mm of that falling in only one hour. 394mm was recorded in the six hours to 1 am today.
Halifax was one of four locations in the area to record 24 hour rainfall totals exceeding, or near, 500mm in the 24 hours to 9am today. Cardwell Range recorded 552mm, Lucinda recorded 500mm and Ingham recorded 485mm. Townsville saw 138mm, while around the Cairns area totals ranged from about 50mm to above 100mm.
The totals represent new daily rainfall records for both Halifax and Cardwell Range, while Lucinda recorded its highest rainfall total for a December day.”

South Queensland
BoM also said that, while not related to ex-Tropical Cyclone Owen, south east Queensland also saw significant rainfall to 16 December.
Flash flooding has cut roads on Queensland’s Darling Downs. Local media reported that the flooding had swept several cars off the roads.
BoM said “Totals for the 24 hours to 9am include 157mm at Pomona, 58mm at Ipswich and 91mm at Mt Nebo, with further falls continuing throughout today. Thunderstorms are expected to continue through parts of the south east today.
Social Media
We've crunched the numbers and the 681mm recorded in 24 hours to 9am Saturday the 16th of December at Halifax in #NQld is a new Australian December daily rainfall record☔. I.e. No location in Australia has ever recorded more rainfall in a day in December. Now that's wet!
— Bureau of Meteorology, Queensland (@BOM_Qld) December 17, 2018
Compare the satellite image to today’s overhead shot – huge amounts of water! pic.twitter.com/2OqZK1VfLI
— Arlie Felton-Taylor (@afeltontaylor) December 17, 2018
https://twitter.com/HenryPe16151947/status/1074239653316780032
This satellite imagery reveals the explosive thunderstorm activity occurring around ex-tropical #CycloneOwen this morning. A powerful reminder that even though Owen is now a low pressure system it can still have significant impacts. Warnings: https://t.co/1jImI420dS pic.twitter.com/lqO3QKovFR
— Bureau of Meteorology, Queensland (@BOM_Qld) December 16, 2018