A cold front will near Kauai Tuesday, with a chance of heavier showers by Tuesday afternoon, especially for the Garden Isle. Meanwhile, an upper trough approaching from the west will increase instability, bringing the threat of heavier showers and isolated thunderstorms Tuesday night into Wednesday over Kauai and perhaps Oahu as the front stalls.
Ahead of the front, light to locally moderate southeast to southerly winds are bringing passing spotty showers, mainly over the western half of the state. There are also some pop-up showers that have developed that should dissipate by late night.
The upper trough is forecast to remain in the area as breezy trade winds return for the second half of the week, so expect wetter conditions as enhanced showers ride in on the trades. Some of the showers may be heavy at times.
Surf for north and west shores is declining through Tuesday night, but the Kohala and Kona shorelines of the Big Island will still have waves at or above the high surf advisory threshold into Tuesday. The waves are expected to build again as a new moderate northwest swell peaks Wednesday through Thursday. Surf along east shores will trend slightly lower through mid week, then ramp up late in the weak with increasing trade winds. Surf along south shores will remain small all week.