Andy Murray is hoping tropical storm Hanna will help him dump world No1 Rafael Nadal out of the US Open in tomorrow's semi-final, but the predicted heavy rain and strong winds could mean the match is delayed.

The storm's path is due to bring it to New York tomorrow and both men's semi-finals and the women's final could be washed out, forcing the programme to be moved to Sunday and the men's final switched to Monday.

Murray, who has lost all five previous contests with Nadal, including a Wimbledon quarter-final, believes he can seriously trouble Nadal if the rain holds off and allows the players onto court.

It may appear as if Murray is grasping at straws against the French Open, Wimbledon and Olympic champion, however, the British No1 is adamant his opponent does not like a blustery court.

Murray is more confident about his abilities than at any time in his professional career and said: "Yes, he has got a good record against me and is playing the best tennis of his career, but it's going to be windy and I don't think he likes those kinds of conditions much. The weather is going to be tricky and I am looking forward to it.

"There are better draws out there in terms of who you could meet in a semifinal but if you are going to win Grand Slams then you have to beat the best players and I am capable of beating him.

"I am a different player now than even at Wimbledon a few months ago. I am the No4 player in the world, playing with more confidence and I have beaten some tough players."

With Jamie Murray losing in the mixed doubles final with Liezel Huber 7-6, 6-4 to Leander Paes and Cara Black yesterday, it is down to the junior member of the tennis family to keep the British flag flying in the hurricane winds.

But Nadal, playing in the last four at Flushing Meadows for the first time, is confident he can get past Murray.

He said: "I know I have to play well and get at him. I must keep up my rhythm. He runs a lot and I must make him tired. I must keep up the intensity.

"I have a high regard for Andy, always. Even when we were young. I know how well he can play because we know each other so well. I think I did well at Wimbledon - it was my best match against him.

"It means nothing that this is his first semi-final. I am not playing someone who doesn't know how to deal with the situation.

"It's true I have played more semi-finals than him but he has had some important matches in his career and won them.

"He's playing with a lot of confidence and he knows what it takes and what he has to do in big matches."

Defending champion Roger Federer is pinpointing the Olympic doubles gold he won with Stanislas Wawrinka for helping him into a record 18th successive Grand Slam semi-final.

He defeated Gilles Muller, 7-6, 6-4, 7-6 and now faces third seed Novak Djokovic, a 6-2, 6-3, 3-6, 7-6 winner over Andy Roddick in front of a partisan New York crowd.

Federer said: "I am in good spirits at the moment because of the Olympic gold. It definitely helped to make me more outgoing on court, because I am always like this, especially in practice.

"I guess, for a while, I put my head down in the matches and just tried to keep that unbelievable run I had going instead of trying to disturb myself."

Today's women's semi-finals see Serena Williams take on Dinara Safina and Jelena Jankovic up against Olympic champion Elena Dementieva.