Residents of Lord Howe Island are preparing for gale-force and destructive winds late on Thursday and into Friday as Tropical Cyclone Uesi continues tracking south into the Tasman Sea.

The category-two cyclone is expected to weaken as it makes its way towards the tiny island, which is 600 kilometres off the NSW coast and home to 400 people.

There are also about 400 tourists there, and plans are being made to manage those unable to leave if flights are cancelled.

"It's still a reasonably serious weather system and we are taking appropriate action to prepare for that," Lord Howe Island Board chief executive Peter Adams said.

The Bureau of Meteorology is warning residents on the island to expect gales with gusts up to 120km/h and swells of more than five metres.

A Qantas spokesperson said Thursday's flights were unlikely to be affected. The airline had not yet made a decision about Friday's services.

Mr Adams said precautions included getting earth-moving equipment in place to allow flooded creeks to be opened, clearing roadside drains and the "renourishment" of areas hit by coastal erosion.

Accommodation on the island is at capacity and authorities are trying to make sure everyone has a bed.

"All things being equal, the people that can't get off the island are cancelled out to some degree by ones that can't return here, but there's a lot of adjustment that goes on to accommodate those people," Mr Adams said.

Tourists face being trapped as Cyclone Uesi moves in_1
Cyclone Uesi's path early on Thursday morning (ADST). Image: Bureau of Meteorology

Josh, who lives on Lord Howe Island, said he could see Uesi approaching and was preparing to "batten down the hatches".

"Everyone's just kind of getting ready, it's getting pretty eerie and overcast here already but I don't think it's going to be anything too serious until tonight," he said.

"I'm a plumber, so I've got a pretty busy day getting everyone ready."

Mike Funnell from the BOM said the system would not affect the NSW mainland.

"It will slide to the west of Lord Howe Island, where we expect damaging winds and large swell as early as Thursday evening," he said.

"As the cyclone system moves south, it's going to weaken and that means it will be reclassified as an ex-tropical cyclone.

"It can still have quite considerable impacts though, we're expecting the sort of impacts onto Lord Howe Island that you would normally see from a category one or possibly a category two system."

Mr Adams said the island, which was isolated and without mobile phone coverage, "organises itself differently".

"People live close to each other, they're very connected and they're very experienced in this," he said.

"The SES [State Emergency Service] have been meeting with all the other emergency services, so the usual emergency response agencies are here – it's just that they're all volunteers from a very small community."

While the cyclone won't hit the NSW coast, it is expected to produce large swells, high tides and strong winds over the weekend.

A large inland trough will also continue to bring storms and potentially heavy rain to large parts of the state over the coming days with isolated falls as heavy as 50 millimetres in some areas.

-ABC