Hector was a strong Category 3 Hurricane early Wednesday morning (local time), and looks to remain a major hurricane through at least Friday midday as it moves west and continues to weaken into the weekend.
Hurricane Hector has maximum sustained winds of 130 miles per hour (215 kph) with stronger gusts possible.
A Category Four storm on the Saffir Simpson scale is capable of doing widespread major structural and infrastructure damage; it can easily tear off roofing, shatter windows, uproot palm trees and turn them into projectiles that can kill people.
As a precaution, Hawaii County officials have closed three beaches - Whittington, Punaluu and Milolii beach parks - on Tuesday.
Forecasters expect little significant change in Hector's strength in the coming days. Hector is expected to pass approximately 165 miles south on Wednesday.
A tropical storm warning was in place Wednesday for the Big Island with gusty winds, rain and unsafe surf possible.
Hawaii County Civil Defense urged residents of the Big Island to follow safety measures, such as securing loose objects, especially boats, and residents living on the oceanfront are told to be on alert for "high and risky surf conditions". "The strongest winds are expected down the slope of the mountains, across elevated terrain, over headlands, and through gaps".
A high surf advisory has also been issued for east shores of Maui.
"Tropical storm conditions are expected across portions of the Big Island on Wednesday as the core of Hector passes to south".