Arnhem Land's remote north coastline and islands are now expected to be hardest hit by Tropical Cyclone Monica.
Residents in the Aboriginal community of Nhulunbuy have already been urged to seek shelter, but the weather bureau says the harshest wind gusts are probably going to pass further north.
The bureau's acting regional director Mike Bergin says Monica is expected to reach the Northern Territory coast over the next 24 hours.
And he says Nhulunbuy's four thousand residents should miss the worst of
it with wind gusts of up to 150 kilometres per hour, rather than the predicted 320 kilometre winds.
"It's the outer rain-bands that are going to affect Nhulunbuy, but the islands just off the coast- the Wessel islands- are probably more likely to experience serious conditions later this afternoon and this evening. I know in the case of some of the communities some people have had to be put into cyclone shelters. But the preparations have varied from place to place".