A tropical low that traversed from Western Australia into central portions of the country late last week has since dissipated, but tropical moisture supplied by the low remains across the region.
As a cold front pushed to the east into this moist air early in the week it will develop numerous showers and thunderstorms from Alice Spring, southward into Victoria and New South Wales.
Parts of this region has seen 25-75 mm (1-3 inches) of rain during the last week, so additional heavy thunderstorms could trigger isolated flooding. In Alice Springs 161 mm (6.33 inches) of rain has fallen during the last four days, which has already lead to flooding in the region.
As low pressure develops on Monday near Kangaroo Island, south of Adelaide, a cold front will push north and east across South Australia and into the Northern Territory. Downpours could bring in excess of 50 mm (2 inches) of rain to southeastern South Australia.
In advance of this front on Monday, while there will be a few showers and storms from Brisbane to Sydney, much of New South Wales and Victoria will be dry and very warm.
However, these areas will not be dry for long as the front continues to march to the east sparking numerous showers and thunderstorms for Tuesday.
As the front clears a region, drier and less humid will replace the tropical airmass that has been dominate across central and southeastern Australia much of last week.