She said confirmation of tornadoes relied on one being witnessed, or impacting people and buildings, and therefore records of them occurring are not very accurate or extensive.
Ms Imielska pointed to the tornado that caused significant destruction in Kurnell, in Sydney’s south, in 2015.
“We could see from that aerial photography, a very clear track of that tornado,” she said.
One man, believed to be aged in his 40s, was assessed for an arm injury after the tornado destroyed a property at Meadow Flat, near Lithgow. He was taken to Orange Hospital in a stable condition.
NSW Ambulance Inspector Meah Ferguson said the patient was lucky to have escaped with relatively minor injuries.
“It’s not every day you get called out to a tornado and this one packed quite a punch,” she said.
“When we arrived on scene we found extensive damage to the patient’s dwelling and surrounding areas.”
In Clear Creek, one male suffered cuts to his face while a female patient had sustained back and neck injuries. She was taken to Bathurst Hospital in a stable condition.
A severe thunderstorm warning was issued at 5pm extending across the state, including Sydney. The bureau said the storms were likely to produce damaging winds and heavy rainfall that may lead to flash flooding.
Hail stones of up to two centimetres in size were reported on Thursday afternoon in Castle Hill and Pennant Hills, and further thunderstorms were possible on Friday, the bureau said.
Thunderstorms redeveloped over Parramatta on Thursday night, moving towards the south-east.
They were forecast to affect Sydney City, Sydney Airport, Sydney Olympic Park and the Sydney Harbour Bridge by 6.40 pm and Botany, Maroubra and Randwick by 7.10pm, but conditions “temporarily eased” before they eventuated.
“The redevelopment of severe thunderstorms remains likely,” the bureau said. “The situation is being closely monitored and further detailed warnings will be issued as necessary.”
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