The Met Office says harbours in Douglas and Ramsey could face flooding this lunchtime.
A yellow warning has been issued for inner harbour flooding at high tide at 12.40pm.
Areas at risk are the Tongue and the car parks and riverside at Lake Road in Douglas as well as Mezeron Corner and West Quay in Ramsey.
Lake Road has already seen flooding this morning as heavy rain led to the River Glass overflowing its banks.
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