He was pushed hard by the Serbian fourth seed in the rain-delayed semi-final but improved his record against Djokovic to 9-4 as he controlled the key moments.

BBC: Federer & Del Potro into US final

One way to increase the probability of rain is to seed the formation not of water droplets, but of ice crystals, an important step in precipitation.

ECONOMIST: Aerobiology

"Bad weather in spring prevented honey bees in many areas from collecting nectar from early flowering crops such as oil seed rape, and the rain continued in many places throughout June and July preventing honey bees from foraging on later crops, " he said.

BBC: Honey harvest 'devastated' by wet summer

"I'm very happy for that, " the world No. 5 said after overcoming multiple rain delays to beat French 13th seed Richard Gasquet 7-5 7-6 (7-2) 6-4.

CNN: U.S. Open: Ferrer finds fortune as rain hits New York courts

Top seed and world number one Lindsay Davenport is on Court Four wacking balls left, right and centre as she bids to get back in the zone before resuming her rain-affected semi-final tussle with the number three seed Amelie Mauresmo.

BBC: SPORT | Tennis | Wimbledon blog

Lopez, the 31st seed, made a superb start, forging a 5-2 lead in the first set before rain forced the players off.

BBC: Safin books meeting with Federer