The tropics are full of activity this morning with one cyclone expected to weaken over the next 24 hours and another expected to form by the weekend.

In its latest update issues at 7am today, The Weather Channel said tropical cyclone “Fina” was located over the Coral Sea, about 950 km to the northeast of Mackay.

The cyclone was category 1 and was expected to weaken over the next 24 hours and not directly impact the Queensland coast.

However it was expected to produce large oceanic swells along the south and central parts of the Queensland coastline across the weekend, Weather Channel senior meteorologist Dick Whitaker said.

The swells could extend down to the New South Wales coast early next week.

A cyclone watch has also been issued for the coastline of the Top End of the Northern Territory, including the Darwin area, for a developing tropical low located at 7am about 330km to the north-northeast of Darwin. This system may develop into a cyclone on Saturday morning.

A flood threat advice has been issued for the Darwin Daly and Arnhem Districts of the Northern Territory with falls in excess of 300 mm expected over the next 4 days.

A low pressure trough is expected to generate a band of showers and thunderstorms stretching from north-eastern Victoria to the Gulf of Carpentaria in Queensland today, with the activity peaking this afternoon.

This band will contract eastwards during Friday and across the weekend, but another active trough will move across south-eastern Australia on Sunday and Monday, triggering a further burst of showers and thunderstorms for Victoria and south-eastern New South Wales. This may generate thunderstorm activity for Melbourne on Christmas Day.