Communities in Maldon, in Essex, are being advised to move pets to safety, avoid coastal paths and promenades, and postpone road journeys where possible.
It comes as the Environment Agency issued flood warnings for Norfolk, Suffolk and Essex.
High tide is expected in Maldon just before 5pm.
The Environment Agency is warning that businesses and homes alongs the waterfront and The Hythe could be at risk.
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A chilly evening but cloud thickening with outbreaks of rain spreading from the west after midnight. Lows of 2 deg C (36 deg F).
Crews are working against the clock this weekend to repair damaged bridges over the A47 in King's Lynn.
Hybrid Air Vehicles said the aircraft has now been stabilised and made completely safe to work on.