Iselle lost steam as it lashed Hawaii with strong winds and heavy rain early on Friday, as a second, more powerful storm headed for the holiday paradise.
While forecasters downgraded Iselle to a tropical storm from a hurricane shortly before it was due to make landfall on the Big Island, the ferocious system still spawned dangerous swells, cut power and snapped trees.
Lurking not far behind was Category 3 Hurricane Julio, packing maximum sustained winds of 120 miles (195 kilometers) per hour as it, too, approached the popular archipelago, the Central Pacific Hurricane Center said.
The eye of Iselle was still some 45 miles from Hilo, on the Big Island, according to the latest CPHC update.
But that did not stop it from unleashing damaging wind and rain, with local media reporting power outages, downed trees and road closures.
Rainfall of up to 12 inches (30 centimeters) was expected, with forecasters warning of "life-threatening flash floods as well as rock and mud slides."
Authorities took no chances, telling people to stay indoors, shuttering all non-emergency public facilities and sending employees home from work early. Schools were designated as shelters.
Precipitation fell on the wind-turbine dotted arid northwest of Maui island, where locals say it almost never rains, and gusts were picking up markedly ahead of Iselle's arrival.
As the second largest Hawaiian island, Maui lies directly north of the Big Island and its 150,000 residents annually welcome 2.5 million tourists.
Even the public beaches closed down, although on Thursday, sun seekers jumped the waves, ignoring red flag warnings of hidden riptides.
Maui authorities banned dive and snorkel boats from setting out to popular areas, including the unspoiled half-sunk crescent-shaped Molokini crater famed for its undersea coral reef.
Some hotels and residential complexes closed their pristine pools, and disappointed guests found they could not rent boogie boards or paddleboards to brave the swelling waters of the Pacific Ocean.
Rush on supermarkets
Iselle may have been downgraded, but it was still accompanied by top winds near 60 miles per hour, CPHC forecasters said, adding it was expected to further weaken over the next two days.
Residents and tourists, confined to their homes and plush hotels, took to social networking sites to describe how the storm was impacting them.
"Wind is getting kinda freaky. shutting down my reserve power now. stay safe everyone," wrote @DeniseLaitinen on Twitter.
Hours before Iselle's impact, Island Air announced it was cancelling all its inter-island flights scheduled for late Thursday and Friday. Hawaiian Airlines also dropped connections, while United Airlines and US Air snapped links with mainland Los Angeles and Phoenix.
"We all need to stay alert, pay attention, and work with the emergency management agencies across the state," governor Neil Abercrombie told reporters.
Julio, the fourth major hurricane of the Eastern Pacific season, was about 970 miles east of Hilo, according to the CPHC. On its current trajectory, it was forecast to pass to the north of Hawaii starting late Saturday.
As the twin storms neared, long lines formed at local supermarkets, as residents and vacationers alike rushed to stock up on water, bread and batteries to ride out the rough weather.
State authorities warned that price gougers would be severely punished.