The Bureau of Meteorology is keeping an eye on a monsoon trough in the Coral Sea that is threatening to develop into a tropical cyclone by Monday.

As ex-tropical cyclone Seth peters out after finally reaching land on Friday, the bureau says another could be developing as it approaches the Cape York peninsula. The next cyclone is likely to be named Tiffany.

“There is a moderate chance of a tropical cyclone forming (from the monsoon trough) in the northwest of the Coral Sea,” BOM hazard response co-ordinator Brooke Pagel told AAP.

She said the trough was set to develop into a tropical low and drift over the Cape York peninsula, intensifying when it entered the Gulf of Carpentaria by Monday.

“That’s where we are expecting it to really ramp up and maybe form into a cyclone,” Ms Pagel said.

A cyclone watch for the far north may be issued as early as Saturday.

The monsoon trough is set to cause heavy rain and isolated thunderstorms across the Cape York peninsula and Torres Strait in the coming days.

A flood watch may also be issued for far north Queensland catchments as early as Friday afternoon.

Meanwhile, former cyclone Seth is petering out as it finally reaches land after causing massive swells along the coast this week but it is still making its presence felt in the south-east of the state.

Thunderstorms are set to hit in the coming days after Seth’s remnants crossed the coast in the Wide Bay area north of Brisbane on Friday.

The south-east was expected to receive up to 30mm of rain on Friday with Wide Bay the worst hit, while isolated showers could reach totals of 50 to 120mm in Gladstone, the Sunshine Coast and Kingaroy in the coming days.

“Seth has now completely weakened but there will be heavy rain with showers and thunderstorms set for the next few days in the southeast,” Pagel said.