Cyclone Trevor has struck the Northern Territory as a category four system, hammering remote communities with destructive 250 km/h winds and torrential rain.

It was one of two monster storm fronts bearing down on northern Australia this weekend – cyclone Veronica was hurtling towards the Pilbara region in Western Australia.

Trevor crossed 100 kilometres south of Port McArthur at about 10am local time.

Bureau of Meteorology NT manager, Todd Smith said there had been massive storm surges including one of 1.5m recorded at Mornington Island.

“As it gradually weakens in intensity while it moves inland we are expecting it to remain at tropical cyclone strength through until tomorrow morning,” Smith said.

NT regional controller Travis Wurst said authorities were conducting damage assessments at Numbulwar and Groote Eylandt, to determine when evacuees can return home.

“At this stage no injury of no loss of life has occurred,” he told reporters on Saturday afternoon.

Wurst urged people to stay inside even after the storm front had passed.

“Even though the cyclone may have left the area where you are, we’d urge you not to go outside to explore the damage. There may be downed power lines or other hazards. We don’t want to see anyone putting themselves in danger,” he said.

The NT chief minister, Michael Gunner, visited an evacuation centre in Darwin on Saturday morning and said the people were calm. He had declared a state of emergency earlier this week.

“We are expecting a large recovery effort,” Gunner told reporters.

“There are lot of volunteers and emergency services workers busting their guts to ensure everybody is being looked after.”

Severe Tropical #CycloneTrevor is starting to make landfall - sustained winds of 95km/h gusting to 115km/h at #CentreIsland, just off the coast near #Borroloola, very destructive wind speed of 175km/h near the centre, gusting to a wild 250km/h! https://t.co/xp4kOCYpTU pic.twitter.com/HOtFVknONw — Bureau of Meteorology, Northern Territory (@BOM_NT) March 23, 2019

Kerry and Gavin Enever are the managers at the 306,000 hectare Pungalina-Seven Emu Wildlife Sanctuary and preparing for a sleepless night, as the homestead is battered by 150 kilometres an hour winds.

“We would have had three inches (of rain so far),” Gavin told Guardian Australia.

“We’re either right at the edge of the centre now or it’s starting to tail off a little bit, it’s really hard to tell.”

Gavin was shocked by the ferociousness of the wind, despite being 60km inland.

“You can’t stand up in it. Even in the hallway you can’t stand up. It’s blowy,” he said.

Kerry said the boat is tied up underneath the house, because the homestead is 50m from the Calvert River.

“We expect a bit of flooding in the next day or two,” Gavin said.

The river last flooded two years ago and was lapping at the front step and then in the 2010 flood there was water under the floor boards.

“Everything has been packed up. All the machinery is high up on a hill,” Kerry said.

The Northern Territory incident controller Brendan Muldoon told ABC Darwin radio on Saturday morning it would hit McArthur River Mine as a category two or three system about 7pm (local time) on Saturday night.

Between 100 to 200 millimetres of rain a day was expected along with isolated falls of up 350mm.

The Carpentaria highway, Roper highway, Barkley stock route and the Tablelands highway had been closed, and some reports said this had frustrated some pastoralists trying to move their cattle to safer ground.

William McMillan decided not to evacuate from Calvert Hills cattle station near the Queensland border, because he was worried about poor access getting back.

He was about 80km south of the eye of the storm.

“It’s getting a little bit hectic,” he told ABC radio. “Only had 20mm of rain so far but it’s on its way.”

His wife and children had gone to Conclurry, Queensland.

“I’ve put all the kids toys under cover ... (you don’t want) a trampoline flying through a window,” he said, adding that the cattle were in good physical condition.

Four people on Vanderlin Island had refused to leave and six had opted to stay behind at Borroloola, against advice.

Muldoon said survey teams were on standby at strategic locations to assess the damage and restore critical infrastructure such as power and water when safe.

They would also be ensuring that airfields were clear for planes to land to bring in supplies.

By Sunday afternoon, forecasters believe Trevor would have weakened below cyclone strength, reaching Tennant Creek, 1000km south of Darwin, as a tropical low in the evening.

An evacuation centre was set up in Tennant Creek for those from 14 nearby outstations.

Here's a map showing the locations where we have data to record rainfall, wind speed and direction around #CycloneTrevor. We use satellite and radar imagery and modelling to understand and estimate wind speeds nearer the centre of Tropical Cyclones https://t.co/MKdTaHVUN8 pic.twitter.com/vquBXqDHAY — Bureau of Meteorology, Northern Territory (@BOM_NT) March 23, 2019

Volunteers busy unloading fresh supplies at the evacuation zone in South Hedland. It’s fast filling with people as Severe Tropical Cyclone Veronica approaches @abcperth @abcnews @ABCemergency pic.twitter.com/g1uFz5wvTP — James Carmody (@jamescarmody95) March 23, 2019

In Western Australia, people in Port Hedland and Karratha were bunkering down for Cyclone Veronica, which was also expected to be a category four system and was due to hit the Pilbara region about 8am AWST on Sunday.

“Mixture of nerves and anticipation It’s definitely calm before the storm at the moment,” Lucy Guy told the Guardian.

She was waiting out the storm at South Hedland with her fiance.

“Our power is underground so hopefully we can keep watching Netflix,” she said.

“Roads are starting to flood from rainfall already and it’s still around 20 hours until the real fun starts.”