Waveney District Council is urging residents in threatened properties to vacate them as soon as possible.
The council says reports suggest that the tide is far higher and far earlier than expected, and that residents should not presume to wait until immediately before the predicted surge peak at around 11pm.
A spokesman said: “We are basing this on reports from Oulton Broad and Mutford Lock where the water is already brimming the barriers - it’s higher and sooner than we thought.”
The rest centres in Lowestoft, Kessingland, Southwold and Carlton Colville are now open and receiving people.
He said the Oulton Broad road bridge is to be closed shortly because water levels are now too high for cars to cross safely.
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