The Central Pacific Hurricane Center on Monday issued a hurricane watch for the Big Island of Hawaii, saying Hurricane Madeline could pass "dangerously close."
The storm should be near or over the Big Island by Wednesday, said forecaster Derek Wroe.
At 11 p.m. Monday (2 a.m. PDT Tuesday), the center said the storm had strengthened to a Category 4 hurricane with maximum sustained winds near 130 mph.
The Center's advisory on Madeline predicted it will pass "dangerously close" to the Big Island Wednesday and Wednesday night. But it added that some weakening is forecast through late Wednesday.
Residents could experience hurricane force winds, heavy rain and high surf, the Center said.
Madeline was 515 miles east of Hilo late Monday night and moving west-northwest at 9 mph.
Hawaii County, which covers the Big Island, urged residents to restock their emergency kits with a flashlight, fresh batteries, cash and first aid supplies.
The county recommended that residents create evacuation plans and secure outdoor furniture.