QUEENSLAND's south east region is on high alert with the Bureau of Meteorology warning localised thunderstorms may dump more than 200mm in some areas.
The heavy rainfall currently deluging the south east region should gradually move south into NSW on Tuesday.
The official forecaster says six-hourly totals of between 80-140mm are possible, reaching up to 180mm over coastal areas and the ranges.
A severe weather warning is in place for the south east coast and parts of the Darling Downs and Granite Belt.
BOM says severe thunderstorms with locally heavy rain are also possible for the Darling Downs and Granite Belt and Wide Bay and Burnett districts.
A major flood warning is current for Myall Creek, which runs through Dalby.
A moderate flood warning has been issued for the Condamine River, following rapid rises in upper parts of the catchment this morning.
BOM says with many catchments now saturated, there is an increased risk of dangerous and life-threatening flash flooding and even landslides.
Flood watches have been issued for large parts of southern Queensland and north east NSW, with minor to moderate flooding expected in several areas.
BOM says major flooding is also possible for some communities recently impacted by severe weather.
Over the border widespread rain and severe thunderstorms are expected for the Northern Rivers and parts of the Mid North Coast and Northern Tablelands.
BOM says there is the potential for major flooding for the Richmond, Wilsons, Orara and Bellinger rivers including Lismore and other communities recently impacted by severe weather.
The localised flooding seen over the past week will likely become more pronounced with riverine flooding from the Mid North Coast through to the Northern Rivers, Northern Tablelands and North West Slopes and Plains.
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