The National Weather Service in Honolulu has issued a marine weather statement that a north-northeast swell is peaking Sunday night and Monday morning.
This swell will produce surges in north facing harbors, including Hilo and Kahului harbors.
Observers have already reported water in the adjacent roads to Hilo Bay.
High tide will be around 6 a.m. Monday and this will be the most susceptible time for harbor surges.
Mariners using these harbors should also exercise caution when entering or leaving port and then mooring or launching vessels.