Terrifying new weather maps show the expected path of Hurricane Ernesto as it heads towards the tropical island of Bermuda . The ferocious storm dropped torrential rain on Puerto Rico and knocked out power for nearly half of all customers in the US territory yesterday and still threatens to strengthen into a major hurricane in the hours to come. The storm was over open water about 675 miles south-southwest of Bermuda early Thursday, with maximum sustained winds of 85 mph and moving northwest at 16 mph.

Now, a hurricane watch has been issued for Bermuda, where people are braced for tropical storm conditions on Friday and hurricane conditions on Saturday. Schools and government agencies were closed in the U.S.

and British Virgin Islands and Puerto Rico, where heavy flooding was reported in several areas, forcing officials to block roads, some of which were strewn with trees. More than 140 flights were cancelled to and from Puerto Rico. "A lot of rain, a lot of rain," Mayor of Culebra Edilberto Romero said in a phone interview: "We have trees that have fallen on public roads.

There are some roofs that are blown off." Flash flood warnings have remained remained in place after the hurricane passed because of continuing rain. Ernesto, a Category 1 hurricane, is gradually strengthening and could become a Category 3 hurricane by Friday.

Its centre is expected to pass near Bermuda on Saturday, and between three and six inches of rain is forecast, with more possible in isolated places..