Authorities on full alert as Cyclone Oma's threat grows
THE Bureau of Meteorology has gone on 24-hour watches with all hands on deck as Cyclone Oma draws closer to the southeast Queensland coast.
BOM forecaster Adam Blazak said if the Category Two cyclone stayed well offshore there would be no rain and just a heavy sea erosion impact.
If it closed on the coast, rainfall totals around 500mm may eventuate.
A gale warning for coastal waters the BOM that was expected to have been issue from Friday has been brought forward to Thursday as forecasters watch a range of modelling which to day can't agree on how the cyclone would act.
"We are all hands on deck with extra shifts," Ms Blazak said.
He said the situation was at best speculative, likening it to a ball sitting atop a ridge which could teeter one way or the other.
It wouldn't take much change in atmospheric ridges and troughs for the cyclone to go one way or the other.
Mr Blazak said cyclones had a natural attraction to the poles but some modelling was showing the system even heading back north.
Other scenarios included a close pass of the coast which would bring heavy rain with high totals and huge seas, the system to come straight in and onto the south east Queensland coast and the system turning away to the south east well out to sea and smashing into New Zealand's north island.
"Unfortunately the models jump around beyond three days," Mr Blazak said.
"It will head towards the coast until Friday but from there it's not firmed.
"There will be beach erosion and very dangerous conditions.
"During the next couple of days it will look look keen but even experienced surfers should take care.
"Because of the high tides and long-period swells, rips will develop."
Mr Blazak said it was essential for people to understand weather forecasts could fluctuate over the coming days and to watch for updates.
The BOM says Category 2 cyclone were capable of causing minor house damage and significant damage to signs, trees and caravans.
Heavy damage could be inflicted to some crops, there was a risk of power failure and that small craft may break moorings.
Category Two cyclones could generate destuctive winds with typical gusts over open flat land of 125-164 km/h.