A high surf advisory for north and west shores from Niihau to Maui due to a north-northwest swell remains in effect through 6 p.m. today.
The National Weather Service says the swell will peak early today, then diminish. On Maui, only north-facing shores are part of the advisory.
Surf of 12 to 16 feet is expected along north shores, and 8 to 12 feet along west shores.
Officials warn of strong breaking waves and strong longshore and rip currents, making swimming difficult and dangerous.
Forecasters say another large, northwest swell Wednesday and Thursday is expected to bring warning-level surf.
Surf along north shores is expected to lower to 6 to 10 feet Tuesday while surf along west shores will lower to 3 to 6 feet.
Surf along east shores will be 3 to 6 feet today, and lower to 2 to 4 feet Tuesday. Surf along south shores will be 1 to 3 feet through Tuesday.
The moderate, choppy surf along east shores is expected to subside through the week as trades weaken.
Today is expected to be partly sunny with scattered showers, highs of 76 to 81 degrees Fahrenheit, and east winds of 15 to 20 mph. Lows tonight are from 63 to 68 degrees.
Forecasters said moderate to locally breezy tradewinds will continue today, then diminish Tuesday through Friday as they shift to the southeast.
The rest of the work week is expected to remain mostly dry, with the exception of few afternoon showers for mauka and interior areas. A cold front is expected to stall and weaken near Kauai Friday night, and trades are forecast to return over the weekend.