A search for two bushwalkers missing in the Kosciuszko National Park was called off in the early hours of Wednesday when severe electrical storms swept over the area and the wind chill dropped to -10 degrees.
Police hold serious concerns for the safety of the 65-year-old man and 62-year-old woman, believed to be from Sydney's inner west, who became lost south of Thredbo on Tuesday afternoon.
The couple left Roslyn Lodge at Thredbo at 10am on Tuesday and were intending to walk up Friday Flat Creek towards Brindle Bull Hill, along the Dead Horse Gap, on to Alpine Way and back into Thredbo, a NSW Police spokeswoman said.
However, the woman phoned triple-0 at 2.45pm on Tuesday to say they were lost.
Police had tried to track the couple's location by mobile phone but were unable to do so, the spokeswoman said, and police had not been able to reach the woman again on her mobile phone.
Police from the Monaro Local Area Command launched a search for the couple with officers from the NSW National Parks and Wildlife Services, the State Emergency Service and Fire and Rescue NSW.
They searched until 2.30am on Wednesday, but had to call off the search when weather conditions deteriorated.
"There were severe electrical storms, heavy rain and dreadful winds as well," the police spokeswoman said.
"The wind chill dropped to -10 degrees and the search was called off for the safety of the searchers.
"They also had emergency vehicles placed in high visibility areas with the lights flashing, hoping they would be able to head towards those lights, but nothing has happened."
The police helicopter was also grounded due to the severe weather conditions.
The spokeswoman said the couple were not believed to be experienced bushwalkers, and were not equipped to spend the night in the bush.
The search is expected to resume on Wednesday morning with the help of a Snowy Mountains horse-riding group, who know the area well, the spokeswoman said.
Roslyn Lodge company secretary Lisa Moore said the couple had arrived at the lodge on the weekend and had booked to stay for a week.
She said they had stayed at the ski lodge, which is only available to members and their guests, more than once in the past.
Weatherzone meteorologist Max Gonzalez said weather conditions on the ranges would make things difficult for the missing couple.
"Since midday on Tuesday, the ranges picked up 68mm of rainfall which fell steadily from 6pm," he said.
"Temperatures reached a peak of 7 degrees in the morning on Tuesday but dropped down once the rain came in the afternoon and fell to freezing overnight."
Mr Gonzalez said an extreme weather warning was issued for the Thredbo area on Tuesday although the Bureau of Meteorology cancelled the warning about 3am on Wednesday.
"West-north-westerly winds reaching up to 100km/h were recorded around 6pm on Tuesday evening and this morning winds have been gusting around 90km/h," he said.
- with Henry Belot, Melanie Kembrey
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