The National Weather Service in Honolulu has forecasted a gradual easing of the breezy to locally windy trade winds into the weekend, with a moisture band set to persist over windward and mauka areas from Oahu to the Big Island, producing frequent moderate to light showers through the morning hours. In a statement obtained by the NWS, they anticipate "a drying trend later today into the weekend as a drier and more stable airmass filters in."
According to the weather bulletin, the 1030 mb high northeast of Hawaii is on the verge of somewhat lessening its grip on the archipelago, allowing for a gentle decrease in the windy conditions to more locally breezy levels. Rainfall in the past 12 hours reached over 2 inches in some wetter locations, especially along windward Maui and the Big Island. A shift in the weather pattern will bring a drier airmass from the east, promising to quickly decrease chances of rainfall and likely drop inversion heights to 5 kft or lower by early tomorrow. The approaching drier airmass signals an end to significant rainfall for the area.
Aviation conditions are currently influenced by the strong trade winds, leading to occasional MVFR and isolated IFR conditions over windward parts of the eastern islands, as the high pressure far northeast of the state slowly weakens. The NWS reports foresee improved visibility which might result in the lifting of AIRMET Sierra, the advisory for mountain obscuration. Moderate low-level turbulence over and downwind of the islands is expected to persist, maintaining the need for AIRMET Tango into tomorrow.
The marine forecast continues to warn of moderate to locally strong trade winds across most local nearshore waters driven by a large surface high northeast of the islands. An all-water Small Craft Advisory (SCA) remains effective through this afternoon due to both gusty winds and high seas. It is expected to persist for certain zones eastward until Saturday morning. "A front approaching from the northwest early next week could veer moderate to fresh winds a touch south of east," as stated by the NWS, hinting at a change in wind direction. Swell conditions are also predicted to follow the trade winds trend, with the recent northeast chop projected to subside through the weekend.
Fire weather concerns mirror the general forecast, with breezy to locally windy trade winds set to trend down today through the weekend. While occasional showers may persist, the significant drop in inversion heights tomorrow will introduce a much drier airmass. The High Surf Advisory currently in place for rough east-facing shore surf is slated to expire this evening, signaling calmer conditions moving into the weekend.
