A hurricane warning remains in effect as Iselle bears down on the Big Island today.
The hurricane had weakened slightly but was still carrying maximum sustained winds of 75 mph on Thursday morning and was set to deluge the island with up to 12 inches of rain. Flash floods could threaten lives and property, according to the National Weather Service.
Thursday morning, Hawaii Police were driving through Keaukaha in Hilo, using loudspeakers to urge residents to voluntarily evacuate. Surf was beginning to kick up and bands of rain were moving in around noon.
Iselle was 195 miles east-southeast of Hilo and moving west-northwest at 17 mph Thursday at noon. The system was expected to begin impacting windward areas this afternoon with tropical storm force winds to 40 mph that will build to hurricane winds this evening.
Winds 60 to 75 mph with gusts to 85 mph could damage buildings this evening and tonight as the hurricane passes directly over the island. The storm is expected to break limbs and topple trees and some power poles.
Hawaii County Civil Defense is urging people to stay off roads as of noon today. Damaging winds and loose airborne objects could become hazardous projectiles. A storm surge of 1-3 feet on top of a 2.8-foot high tide around 1:20 p.m. this afternoon could bring flooding along the coast and in low-lying areas especially along the windward side. Surf in the range of 15-25 feet this evening will worsen flood problems in coastal areas, according to an NWS hurricane warning which urges residents to be prepared to leave quickly if threatened by high surf.
People who choose to use hurricane shelters are being urged to leave early so they are not caught in torrential rains and dangerous winds. Those staying at home should finish securing any loose objects, turn off propane sources, unplug small appliances and put their refrigerators on maximum cold and keep it closed in anticipation of possible widespread power outages.
Bathtubs should be filled with water for cleaning purposes in case tap supplies dry up.
Julio meanwhile hit its projected peak strength of 105 mph Thursday morning and developed a clearly defined eye despite moving over cooler water 1,200 miles east of Hilo. The cyclone, moving west at about 17 mph is poised to pass through an area of light vertical shear but also sea surface temperatures in the 77-78 degree range that over the next several days that should gradually weaken the system beginning Friday night, according to NWS bulletins. Julio could still be a Category 1 hurricane as it comes abreast the islands on Sunday. The forecast track shows the system passing just to the north of the Big Island.