The powerful weather system left behind by Tropical Cyclone Ilsa is expected to impact the south-west corner of the Northern Territory throughout Saturday, bringing damaging winds and heavy rainfall to the region.
- The system is forecast to impact southern and central parts of the NT as a tropical low from Saturday morning
- Areas closest to the low could receive up to 100 millimetres of rainfall within hours, with flash-flooding possible
- The low is expected to dissipate late on Saturday
After crossing the northern coast of Western Australia as a category five cyclone late on Thursday night, Tropical Cyclone Ilsa moved inland on Friday before it was downgraded to category two by Friday afternoon.
It is expected to cross over into the NT early Saturday morning.
The Bureau of Meteorology (BOM) has forecast that it will impact communities in the Lassester district and parts of the Simpson, Tanami and Barkly districts, including the town of Alice Springs.
BOM NT senior forecaster Billy Lynch said the system was expected to have dropped below cyclone strength by the time it reached the NT, but would still be at tropical low intensity.
It it likely to bring strong weather, with both a severe weather warning and flood watch current this morning.
“It is going to be moving across the southern NT as a deep tropical low, and it will pack a punch in terms of the weather near the path of the low,” Mr Lynch said.
Heavy rain is expected, inlcuding totals of 50 to 100 millimetres “in just a few hours” closest to the centre, and widespread totals of 30 to 60 millimetres.
“For Central Australia, that’s very heavy rainfall and could definitely produce flash-flooding, and would be a significant safety concern for people out and exposed to that,” Mr Lynch said.
Damaging winds averaging 55 to 65 kilometres per hour with peak gusts of up to 100 kilometres per hour are also forecast.
The system is expected to dissipate over the NT by late Saturday afternoon or evening.
“Because this system is going to be moving across the southern NT very quickly, the weather will deteriorate quickly, but it will clear quickly as well,” Mr Lynch said.
“By later on Saturday, the vast majority of these impacts will have cleared.
“It’s not going to be a prolonged event, but it will be a significant event when it’s occurring.”
Acting Assistant Police Commissioner and Southern Regional Controller Kylie Anderson said the system would bring dangerous conditions.
She urged people in the area to clear their yards of loose objects, stay out of floodwaters and avoid travel wherever possible on Saturday.
The NT has already experienced several major weather events this wet season.
Just before Christmas, a tropical low remaining from Tropical Cyclone Ellie dropped hundreds of millimetres of rain across northern parts of the NT and WA, causing flash-flooding in the remote town of Timber Creek and significant damage to roads.
A separate tropical low early last month caused major flooding in a handful of remote communities, with hundreds of residents having to be evacuated to Darwin.
Mr Lynch said this system was not expected to impact any of the communities that had already been hard-hit this season.