Play at Wimbledon was abandoned at 1745 GMT on Wednesday without a ball being struck in anger, the first wash-out at the championships since 1999.
Rain and blustery winds beset southwest London for the whole of the third day of the grasscourt Grand Slam and the covers never came off the courts at the All England Club.
Encouraged by British Met Office forecasts calling for fewer showers and some bright intervals later in the day, organisers announced several putative new start times but they came and went without any improvement in the weather.
Play was abandoned early because of the rain on Tuesday, while three hours of action was lost to the weather on the opening day of the tournament.
With the first round yet to be completed, organisers have moved the start of play forward for Thursday and Friday.
Matches are now scheduled to get underway at 11 am local time (1000 GMT) on the outer courts, with a 12 am (1100 GMT) start on Centre Court and court number one.
In addition, matches in the men's doubles have been reduced from best-of-five to best-of-three sets up until the quarter-final stage.
If there are further rain delays, the organisers will have to consider play on Sunday, normally a rest day. The last time there was play on the middle Sunday of the tournament was in 1997 after no play was possible for two days during the first week.
Despite Wimbledon's reputation for poor weather, Wednesday was only the 31st day lost completely to rain in 118 editions of championships.