Residents in Hawaii should expect stronger winds and an increase in shower activity as a high-pressure system north of the islands strengthens and moves east. Breezy trade winds are expected to intensify from Friday into Saturday, with some areas possibly reaching Wind Advisory levels and sustained winds near 30 mph. Showers will mainly affect windward and mauka areas, occasionally extending to interior and leeward regions, according to the National Weather Service (NWS) Honolulu Forecast Office.
The strengthening winds and pockets of drier air will also raise fire weather concerns for Friday and Saturday. The National Weather Service has issued a Fire Weather Watch for leeward and central parts of the islands, where drought conditions are most severe on the Big Island’s northern areas. The watch will be in effect during late morning and afternoon hours when humidity levels drop and winds increase, creating conditions that may meet critical fire weather thresholds.
Marine conditions are expected to become rougher as the high-pressure ridge strengthens trade winds into the fresh to near-gale range through Saturday. The National Weather Service has expanded the Small Craft Advisory to cover all Hawaiian waters, with north-northwest swells expected to raise wave heights to around 10 feet.
Surf along north and west facing shores is forecast to reach High Surf Advisory levels due to two separate north-northwest swells. The first swell has 11 to 13 second periods, while a second, longer-period swell of 15 to 17 seconds is expected to build through the day, potentially pushing surf to advisory levels.
By Sunday, heavier rainfall is possible as a plume of tropical moisture moves north and an upper-level low approaches the islands. This pattern will bring wetter and more unsettled trade wind conditions into early next week as the high-pressure system weakens and trade winds ease.
