Here’s what the Big Island of Hawaii faces Thursday afternoon and evening as Hurricane Iselle makes landfall, with sustained winds of about 75 mp expected along with torrential rain and high surf/storm surge. This advisory below is from the National Weather Service’s Central Pacific Hurricane Center, which will issue new alerts through the afternoon and night. (And if you’re in Hawaii, and feeling the storm, add a comment to this post or email firstname.lastname@example.org).
Conditions will steadily deteriorate over the Big Island this afternoon, with tropical storm conditions expected to arrive well before dark. Hurricane conditions are likely for portions of the Big Island tonight. Tropical storm conditions are expected over Maui county tonight, and for Oahu late tonight and Friday. Tropical storm conditions are expected for Kauai county later Friday.
Rainfall totals of 5 to 8 inches, with isolated maximum amounts to 12 inches, are expected along the track of Iselle. These rains could cause life-threatening flash floods as well as rock and mud slides.
Swells generated by Iselle will continue to build along east facing shores tonight. Very large, damaging surf is expected along mainly east and south shores starting early Thursday.
The combination of storm surge and the tide will cause normally dry areas near the coast to be flooded by rising waters. The water could reach the following heights above ground if the peak surge occurs at the time of high tide,.
Big island windward and Kau, 1 to 2 ft.
The highest water will occur along the immediate coast in areas of onshore flow. The surge will be accompanied by large and damaging waves. Surge related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.