It is scheduled for midday local time here, although organisers say "minor changes" to the programme of the ceremony may still be made.

The Hellenic Olympic Committee did give serious consideration to switching the ceremony to a giant lecture hall at the nearby International Olympic Academy, before unanimously deciding to keep with tradition and brave the weather.

The storm which had been feared finally arrived in Olympia barely minutes after the final rehearsal of the Torch lighting ceremony had been completed. 

The rain turned the track of the Ancient Stadium into a lake.

As a result, even officials will have to stand on the hillside to watch proceedings at the ceremony rather than being seated in the stadium.

Spectators there will be able to follow the action on a big screen for the first time.

A party from the Pyeonchang 2018 Organising Committee, led by its President, Lee Hee-beom, watched proceedings from the sidelines during the rehearsals.

"We already have a successfully lighted flame from Olympia," he said.

"The date on which it is lit is less important." 

There was a worrying delay before the sun appeared during the rehearsal. 

When High Priestess Katerina Lehou finally coaxed a flame from the parabolic mirror, the sense of relief was audible.

This final practice featured the first Torchbearer, Greek cross-country skier Apostolos Angelis. 

He was wearing the yellow and white tracksuit which will become very familiar when the Torch reaches South Korea next month.

"I feel much more relaxed now that we have had this rehearsal," said Angelis, who will compete in his second Winter Olympics in Pyeongchang.

"When I have completed my run, I will have a better sense of the emotion and I shall be able to offer my experiences to others who are running."

On the big day, at the nearby memorial to Olympic founding father Pierre de Coubertin, he will pass the flame to former Manchester United footballer and Olympian Ji Sung Park.

"We chose him because he is not only one of the most successful and renowned Korean sportsmen internationally, but not only that he is known for his work ethic and he always gives his best on the field," said Pyeongchang executive vice-president Kim Jae You.

"He was also part of the Korean team which won bronze at London 2012 so everybody felt he would be the most appropriate person."

The flame will be officially handed to the Koreans in Athens on October 31, after its traditional passage around Greece. 

Pyeongchang organisers promised some innovative ways of transporting the Torch once it lands on Korean soil.

"We will use various means representing the past, present and future to showcase our advances in technology," said Kim.

The Torch is expected to go on an underwater voyage as it did in 2000 and will also be carried by a robot.