The destructive core of tropical cyclone Seroja is moving inland north of Geraldton in Western Australia after wind gusts of up to 170km/h were reported during landfall.

The storm hit the Western Australian coast south of Kalbarri at 8.00pm AWST on Sunday as a category three system.

At 10.00pm AWST the storm weakened to a category two system as it continued moving inland.

Cyclone Seroja is travelling at around 55km/h and significant impacts are expected to extend south and inland through to Wheat Belt communities overnight.

The cyclone will weaken as it moves further inland today but is still likely to result in damaging wind gusts and heavy rain.

A severe weather warning is current for areas to the southeast of the Tropical Cyclone Warning area.

The Bureau of Meteorology’s Todd Smith said the cyclone was expected to cross the coast as a category two but had intensified.

“Even though we had anticipated the system to weaken a little bit, because waters off Kalbarri, Geraldton way are a little bit cooler than further north … the system has maintained if not even intensified.

“So it’s maintaining category three cyclone intensity.”

Smith said very damaging winds were likely for a few hours, with gale force winds lasting longer.

A red alert has been extended to include an area south of the Carnarvon townsite to Lancelin, including the City of Greater Geraldton and Shires of Carnamah, Coorow, Chapman Valley, Irwin, Mingenew, Morawa, Northampton, Perenjori, Shark Bay and Three Springs.

Department of Fire and Emergency Services Commissioner Darren Klemm said towns within the red alert area would experience the impact of the cyclone until after midnight.

“You cannot go outside your home,” Commissioner Klemm said.

“People must stay inside and activate your emergency plan.”

‘Large storm posing a serious threat’

Earlier on Sunday, WA Premier Mark McGowan also urged people to take action.

“This is a very serious situation and people need to heed the emergency advice,” he said.

“Tropical cyclone Seroja is like nothing we have seen before in decades.

“This is a very large storm that is posing a very serious threat. Lives and homes are at risk. We expect significant damage.

“I urge everyone to take this situation seriously. I want everyone to stay safe.”

A yellow alert is also current for north of Carnarvon to Minilya Roadhouse, inclusive, which means there is a possible threat to homes and lives and people need to get ready to shelter.

North of this and up to Coral Bay has been given the all clear.

The Department of Communities opened evacuation centres in Port Denison, Carnarvon and Denham.

‘Avoid movement until all-clear is issued’

Department of Fire and Emergency Services (DFES) incident controller Graham Sears told ABC Radio people subject to a red alert should shelter in a place with four solid walls and minimal windows.

“They need to go to that safe zone that they’ve identified in their house, which … might be a bathroom or passageway that has a good structure around it,” he said.

Sears said people should also listen to the radio and check for emergency updates, avoiding movement until an all-clear had been issued.

“We’re asking people not to take a peek out and go for a wander until we issue the all-clear,” he said.

DFES said there may be some disruption to essential services such as power, telecommunications and water, but authorities were working to limit the disruption.

The Department of Communities has asked some residents in Denham to evacuate.

Gusts of up to 150km/h forecast

Bureau of Meteorology WA manager James Ashley said it was rare for a cyclone to travel as far south as Denham and Geraldton.

“People in coastal paths – particularly in that Shark Bay, Kalbarri area – should prepare for the onset of a storm surge as the system crosses the coast, which is the piling up of water in the onshore flow associated with the system,” Ashley said.

“It can push the ocean across low-lying coastal areas and produce flooding issues.”

Ashley said the worst conditions are expected to last for about three hours at any given location.

The northern side of the cyclone’s track will bear the brunt of dangerous winds and heavy rain, he added.

“Because it’s moving so fast, the onset of these conditions will be quite sudden for people,” Ashley said.

“It may not look too bad at a certain place, but people are warned that these conditions can deteriorate very rapidly because the system is moving so quickly.”

Ex-tropical cyclone Odette weakened overnight, and is set to weaken further after making contact with cyclone Seroja.

Heavy rain expected inland

Cyclone Seroja is expected to bring heavy rain to southern parts of Western Australia after it finishes crossing the coast.

Ashley said the storm would be brief but powerful.

“Rainfall with the system will be short and intense, the system is moving very rapidly,” he said.

“Rainfall will be heavy but for a short period which increases the risk of flash flooding.

“That’s along the whole path of the cyclone from where it crosses the coast and moves inland and out towards the south-east of the state.”

Ashley said wind gusts were likely as far south as Esperance during Monday.