The rising seas prompted evacuations along the eastern English coast, with 1,400 properties flooded and at least a half-dozen communities at great risk of exceptionally high tides and large waves. In London, the Thames Barrier — a series of huge metal plates that can be raised across the entire river — closed for a second time in as many days to protect the city from the surge. Environment Secretary Owen Paterson said there would be “exceptionally high tides” on Friday and Saturday, though they were not expected to reach Thursday’s levels, when water swamped seaside promenades and flooded homes.