Police are hoping for a "window of opportunity" from the bad weather on Mount Cook this morning to rescue two Japanese climbers trapped since last week.
Two helicopters searching for the pair yesterday morning spotted a red tent and a person believed to be one of the climbers waving from near the mountain's summit ridge.
However, they were unable to make a rescue because of the high winds and near zero visibility.
A short window of good weather was expected this morning and rescuers were hoping to drop a radio to the tent site before attempting a rescue, senior constable Brent Swanson said.
The two men, believed to be in their 40s, were due back at Mt Cook Village on Saturday and had not been seen since Friday when they were on the upper Empress Plateau.
Police constable Stu Mori of Tekapo said it was not known what supplies the trapped climbers had.
"We don't know what food and rations (they have), we don't know the medical conditions. It's an unknown factor at this stage," he told The New Zealand Herald.
"Every trip is different. But all climbers are prepared to spend a night out, or two or three nights out, because...that is the nature of the beast with our changeable weather."
Inspector Dave Gaskin of Timaru said last night the situation was very similar to that of one of New Zealand's most famous Mt Cook rescues.
In November 1982 Mark Inglis and Phil Doole, on a training climb, reached the summit of Mt Cook in rapidly deteriorating weather.
The pair quickly realised they had no chance of getting down again and took shelter in a small crevasse just down from the summit to wait for the weather to improve.
On the seventh day a helicopter took advantage of a brief break in the weather to lower to Doole a bag containing food, a small gas stove, sleeping bags and fresh clothes.
Another six days passed before the weather briefly cleared enough again for the pair to be rescued after 13 days trapped on the mountain.
Both men lost their lower legs to frost bite they suffered during the ordeal.
Mr Inglis told The Press yesterady the trapped pair could be facing a tougher situation than he had faced.
"We only came into the storm when we got out on the summit ridge. They were climbing from the west so they've actually been in the brunt of the storm.
Mr Inglis said he hoped the pair had enough supplies to come through in good condition.
"It's going to be very, very cold and it comes down to the equipment you have got."
