Rainfall records have tumbled across Queensland's southeast and northern NSW.
More than 50 sites in the region registered over a metre of rain in a week during 2022, the Bureau of Meteorology says.
The records were broken between February 22 and March 9 with some areas experiencing two and a half times their average monthly rainfall and others five times the amount.
The big wet came as a result of weather systems over eastern Australia and the Tasman Sea where large volumes of humid, tropical air moved onshore.
BoM says a trend has occurred in recent decades of high-intensity, short-duration events, particularly across northern Australia.
Data from the Special Climate Statement 76 reveals that the 2022 southeast Queensland flood peaks haven't been seen since 1893.
But the lower Brisbane, Bremer Rivers and Lockyer Creek peaked below levels experienced in January 1974 and in the 2011 floods.
In the state's north, rainfall records tumbled at the Hughenden, Richmond and Cloncurry airports earlier in May as the inland regions recorded their highest totals for the month.
The bureau attributes the rainfall to two years of La Nina conditions that fell on saturated catchments leading to flash flooding from Maryborough to Grafton.
In NSW, records tumbled at Wilsons River in Lismore, peaking at a record high 14.4 metres on February 28, with the previous record at 12.27m in February 1954.
Heavy downpours across Queensland in May caused the state's sixth major flood event since December with a combined death toll of 28.
Australian Associated Press
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