The US Open men's final was switched from tomorrow to Tuesday (NZ time) for the fifth year in a row after today's semi-final between Novak Djokovic and David Ferrer was suspended because of bad weather.
Britain's Andy Murray won the first semi-final, beating Tomas Berdych 5-7 6-2 6-1 7-6 and Ferrer was leading the second semi 5-2 in the opening set when tournament officials stopped the match because of high winds.
Tournament director David Brewer then announced play had been called off for the rest of the day because of an approaching thunderstorm.
Organisers had already made the decision to move today's women's final between Serena Williams and Victoria Azarenka to tomorrow.
"It was not too difficult a decision to make," Brewer said. "The forecast is for severe weather and we need to give people the time to clear out.
"The goods news is that Sunday is going to be beautiful day."
The men's final has been played on Monday (local time) in each of the past four years, triggering an annual debate and complaints from players and spectators over why the courts are not covered.
The center courts at both the Australian Open and Wimbledon have retractable roofs while organisers of the French Open have announced plans to cover up their main court.
Earlier this year, the United States Tennis Association said they would begin major renovations at Flushing Meadows but ruled out building a roof because of the enormous cost of covering Arthur Ashe Stadium, the largest tennis stadium in the world.
The problem has been exacerbated because the US Open is the only grand slam where both singles semi-finals and finals are played on successive days, leaving no room for catch-up if rain falls on the last weekend.
But Brewer said tournament organisers had agreed to change the format from 2013 so there would be a day between the semis and finals.
"We're getting very tired of having Monday finals," he said.