‘Vigorous’ cold front could bring strong winds, thunderstorms

A “vigorous” cold front could bring strong winds and thunderstorms over the weekend as it sweeps across the state, the National Weather Service warned Friday afternoon.

Southwest, or kona, winds will increase ahead of the front on Sunday, with gusty conditions initially developing across windward communities, as well as any locations over and downwind of terrain, the weather service said. Winds may become strong enough Sunday night and Monday to damage roofs, down trees and cause power outages.

Strong to severe thunderstorms may develop as the cold front approaches Sunday night and Monday. Any thunderstorms during this timeframe could produce damaging wind gusts and hail over any portion of the state.

Heavy rainfall is expected along the front and during thunderstorms. At this time, chances for widespread flash flooding do not appear to be high, the weather service said Friday. However, leeward communities could experience a period of heavy rainfall and potential flood impacts, especially on Maui and Hawaii island later Sunday into Monday.

The powerful low pressure system driving the cold front will generate a large northwest swell that could produce dangerous surf of 20 to 25 feet along north-facing shores of Molokai and Maui and waves of 15 to 20 feet along westfacing shores of Molokai. Homeowners, beachgoers and boaters should prepare for the high surf and significant runup. A high surf warning remains in effect until 6 a.m. Saturday.

The weather service said that it was too early to be specific about the details of the timing or strength of the cold front, but that it would continue to monitor the situation and that members of the public should stay alert for future updates, weather watches and warnings.