Heavy rain, king tide could cause flash flooding in parts of southeast Queensland over the weekend

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HEAVY rainfall and possible flash flooding is forecast as an “unseasonal weather event” hits large parts of Queensland.

The Bureau of Meteorology says the severe weather will stretch from Fraser Island to the New South Wales-Queensland border and extend inland from tomorrow, caused by a developing East Coast Low.

Acting Queensland Regional Director Bruce Gunn said rainfall will increase to a range of 50-150mm in coastal regions of southeast Queensland and northern NSW with the heaviest falls in these areas expected on Saturday afternoon.

“With events like this, localised falls in excess of 250mm are possible, particularly in coastal areas and at elevation including the Sunshine Coast Hinterland and ranges extending south into NSW,” he said.

With a king tide expected and huge seas creating dangerous surf conditions, significant coastal inundation and beach erosion is likely.

Meanwhile, water authorities may be forced to open the gates of southeast Queensland’s Wivenhoe Dam if this weekend’s heavy rainfall is higher than forecast.

The Bureau of Meteorology has forecast 25 to 80mm of rain over the next three days but if the actual rainfall is significantly higher, water could be released from some dams.

A spokesman for Seqwater said it is estimated about 80mm to 120mm of rain would be needed to fall before run-off into the dams started.

A further 15 to 40mm of rainfall could trigger the release of water from Wivenhoe Dam.

Seqwater said they are closely monitoring dam levels and may activate the Flood Operations Centre if the actual rainfall or run-off is higher than expected.

“Based on the current status of the dam catchments and the forecast rainfall, it is possible that catchment run-off will enter the dams, which makes [water] releases possible.”

Currently the ungated Wappa Dam inland from the Sunshine Coast is spilling water and the forecast rain could cause other ungated dams near the coast to spill.

Total forecast rainfall for June 2-5. Supplied: BoM

Fire and Emergency Services Minister Bill Byrne said residents needed to take steps now to prepare their properties and reconsider travel plans in the event of bad weather.

“This is an unseasonal weather event, and residents need to make sure they have plans in place to cope in case they are affected,” he said.

“Parents must supervise their children closely and ensure they stay away from drains, culverts and any flowing water.”

Mr Byrne said motorists needed to have a Plan B in place if travelling on the weekend, including finding alternative routes in case roads were flooded.

“Residents need to pay close attention to weather reports and local conditions before getting behind the wheel,” he said.

“If the road is flooded, forget what car you drive. No-one can predict floodwater or what is happening underneath, so it is important motorists never enter a roadway covered with water.”

“Remember: if it’s flooded, forget it. This simple rule will keep you and your loved ones safe.”

Residents who cannot clean up their own property and require storm and flood emergency assistance should contact the State Emergency Service (SES) on 132 500. In a life-threatening emergency dial triple-0 (000).

BOM spokesperson Richard Wardle said the three biggest weather events over the weekend will be damaging winds, heavy rainfall, and dangerous surf conditions.

“A severe weather warning will be issued early tomorrow morning,” he said.

“Heavy rain is expected and could lead to flash flooding on Saturday afternoon.”

“Damaging winds of up to 90km/h are also expected over the course of the weather event.”

The BOM believe the parts set to be most affected by potential floods will be Fraser Island South and coastal catchment areas, though flooding is not expected to reach a moderate level.

Emergency services are on standby and Deputy Commissioner Mark Roache has advised the people of Queensland to adhere to the rule ‘if it’s flooded forget it’.

“Our message is clear severe weather is coming, and people need to be prepared,” he said.

“Stay away from drains, flooded creeks and ensure you and your family are prepared.”

“Over half, the people that lose their life in floods lose it because they drive through flood water.”

Members of the public are urged to stay tuned for updated forecasts and warnings, follow the advice of local emergency services and not drive, ride or walk through flood water.

Earlier, heavy rainfall and a king tide could cause flash flooding in parts of southeast Queensland over the weekend, the Bureau of Meteorology warns.

Light to medium showers are forecast for Thursday and Friday but the worst of the weather is expected on Saturday.

Flood Ops Centre on alert due to weather forecast. Possible releases from Wivenhoe, Somerset and North Pine https://t.co/a8o0N6Nr5b

— Seqwater (@_seqwater) June 2, 2016

Coastal regions south of Fraser Island, including Brisbane, could receive between 30 to 80mm of rain in one day while stormy conditions may bring more than 100mm to certain areas.

A king tide is also expected on Saturday evening about 9pm, which combined with strong winds and possible gales, could cause flash flooding.

Dangerous surf conditions for #SEQLD coastal areas south of Sandy Cape this weekend. https://t.co/P0iChJgD12 pic.twitter.com/DZsK6s92ey

— BOM Queensland (@BOM_Qld) June 2, 2016

Duty forecaster Lauren Pattie said residents should keep an eye of for weather warnings.

Ms Pattie said the conditions were being caused by upper lows developing over the Great Australian Bight that were moving towards Queensland as well as a surface trough moving east over the state’s interior.

Originally published as Heavy rain, king tide could cause flash flooding in parts of southeast Queensland over the weekend