Today marks four years since a tornado smashed Kurnell

The tornado struck at 10.30am on December 15, leaving a trail of destruction in its wake.

The Bureau of Meteorology later revealed the winds were the strongest ever recorded in NSW. They ripped up trees, overturned trucks and tore down powerlines. Windows and roofs were were sucked from homes and offices. Some homes were completely destroyed.

The road in and out of Kurnell was closed for hours and for many days afterwards only residents and emergency crews were allowed in as the area was declared a natural disaster zone.

Residents were left in shock by the scale of destruction caused by the tornado, which hit just 10 days before Christmas, but counted their blessings that no one was badly hurt.

Celeste McGrath lost part of her home and garage roof.

She was surprised no one was hurt and praised the community spirit in the days after the disaster.

''We are an awesome community. We will support each other through this," she said at the time.

John Curtis arrived home hours after the tornado hit to find another home's roof on top of his own.

Former Sutherland Shire councillor Kevin Schreiber said at the time the damage to homes was "devastating".

''Garages have collapsed, large tree branches have come down on the houses,'' he said.

''People are standing around, still finding it hard to believe what has happened."

Then NSW Premier Mike Baird described the devastation as ''unbelievable'' and pledged state government assistance to those affected.

''The ferocity and the random nature of destruction is incredible,'' he said at the time.

''We should be thankful that no one lost their life ... and residents told me they feel they are lucky to be alive.''

The SES received 700 calls for assistance and the initial clean-up operation took days. Power infrastructure was "completely devastated" by the tornado, and 800 homes and businesses were left without power.

Ausgrid emergency teams were among the first on the scene during the clean-up operations that followed. They were tasked with restoring power to the battered community.

Among them was Ausgrid senior project manager Peter Shori. The 18-year Ausgrid veteran said the emergency crews were in a state of "utter disbelief" on entering the peninsula.

"The tornado swept through fairly quickly. It took a path straight through homes and our Kurnell South zone substation, and right past the former Caltex refinery, and desalination plant," he said.

"There was an unbelievable amount of damage.

"Roofs lifted off homes and buildings, trees and branches strewn across all the local streets, power poles snapped at the ground, and residents wandering the streets trying to figure out what they should do next."

Mr Shori recalled a resident telling him that during the tornado he saw "a large black missile" coming straight for him. It turned out to be a trampoline, which had been tossed aside like a small toy.

As Mr Shori arrived, families were emerging from their broken homes and soon children were outside playing or riding scooters and bicycles just centimetres from downed powerlines..

"My primary focus was on safety and with all the downed powerlines, trying to keep people away from them," he said.

"Even though the powerlines are on the ground, don't assume that they're off or safe to approach. You can be seriously injured if you come near or into contact with those lines."

As the summer storm season gets under way, Mr Shori said it was important to remember never to approach a fallen powerline.