Heavy rainfall, thunderstorms possible starting tonight

Forecast calls for a wet weekend.

Heavy rainfall, thunderstorms possible starting tonight
(Hawaii News Now)

HONOLULU (HawaiiNewsNow) - Thursday is pretty much a transition day in weather; we go from light winds to increased moisture and the return of the trade winds. An increasing moist and unstable air mass will also bring the possibility of thunderstorms and locally heavy rainfall Thursday night into the weekend. We have high pressure up to the north of the islands which keeps the trade winds coming, but the upper trough moving over the islands will bring the added rainfall.

Surf: A new advisory level northwest swell that is expected to arrive tonight, peak on Friday then lower gradually tomorrow night and Saturday. Another reinforcing swell is expected Saturday night and Sunday with another small to moderate swell arriving on Monday. Conditions could be a little choppy with the return of the trade winds.

High Surf Advisory until 6 a.m. Thursday for Niihau, Kauai Windward, Kauai Leeward, Oahu North Shore, Oahu Koolau, Molokai, Maui Windward West, Maui Central Valley, Windward Haleakala.

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