HONOLULU — Hawaii residents rushed to stores to stock up on bottled water, ramen, toilet paper and other supplies as they faced the threat of heavy rain, flash flooding and high surf as a strengthening hurricane continued to head toward the state.

The National Weather Service announced Tuesday night that Hurricane Lane had become a Category 5 hurricane, meaning it is likely to cause catastrophic damage with winds 157 mph or above. The hurricane was about 500 miles southeast of Honolulu.

New forecast just out for rare Category 5 #HurricanLane. Core of hurricane winds forecasted to remain offshore but extreme rainfall and destructive waves guaranteed. Flooding greatest threat to lives and property. pic.twitter.com/LVAHAW7pro — Bill Karins (@BillKarins) August 22, 2018

You do not need a landfall for a hurricane to be a deadly - billion dollar disaster. #HurricaneLane will likely be proof of that because extreme rainfall over mountainous terrain = catastrophic flooding. pic.twitter.com/eXvnTxLMP1 — Bill Karins (@BillKarins) August 22, 2018

Earlier on Tuesday, the weather service had issued a hurricane warning for Hawaii island and a hurricane watch for Oahu, Maui and other smaller islands. This means tropical storm-force winds, excessive rain and large swells could arrive starting Wednesday.

Hurricane Lane "is forecast to move dangerously close to the main Hawaiian islands as a hurricane later this week, potentially bringing damaging winds and life-threatening flash flooding from heavy rainfall," the weather service's Central Pacific Hurricane Center warned.

The storm had been moving west, but it is expected to turn northwest toward the state Wednesday. There's uncertainty to Lane's path — whether it moves north or south, meteorologist Gavin Shigesato said.

A NASA satellite image shows Hurricane Lane southeast of the Hawaiian Islands on Tuesday. NASA / via AP

"It is much too early to confidently determine which, if any, of the main Hawaiian islands will be directly impacted by Lane," the weather service added.

But the hurricane center said the storm will move very close to or over the islands from Thursday through Saturday. Even if the center of Lane doesn't make landfall, the islands could still be hit with heavy rain and wind.

UPDATE: #Lane is officially a dangerous category 5 storm with maximum sustained winds of 160mph. Lane is only one of two category 5 hurricanes to pass within 350 miles of the state according to database records. The last was Hurricane John in 1994. #hiwx pic.twitter.com/dFY0VvTaX8 — NWSHonolulu (@NWSHonolulu) 22 August 2018

Public schools on the Big Island and in Maui County were closed Wednesday until further notice.

Hawaii Gov. David Ige is allowing non-essential state employees on the Big Island and Maui to go on administrative leave from Wednesday to Friday as Hurricane Lane approaches. Employees on Hawaii and Maui islands who work in disaster response as well as in hospitals and prisons are required to report to their jobs, the governor said.

Longtime Hawaii residents recalled a devastating 1992 hurricaneas they prepared for this week's storm.

Kauai resident Mike Miranda was 12 when Hurricane Iniki devastated the island 26 years ago. "A lot of people are comparing the similarities between Iniki and Lane," he said.

All Costco’s on Oahu are sold out of water. This is the water section at Costco Iwilei 24 hours ago compared to now. #HurricaneLane #HIwx #Lane #Hawaii @CivilBeat pic.twitter.com/eruCRF8RnN — Anthony Quintano (@AnthonyQuintano) August 22, 2018

This will allows us to line up services and resources prior so that we can keep our communities safe. Never seen such dramatic changes in the forecast track as with #HurricaneLane. Urging residents and visitors to prepare for a significant impact. More: https://t.co/uFM1uikJDF pic.twitter.com/0266iMnnE8 — Governor David Ige (@GovHawaii) 22 August 2018

Iniki's turn into the islands was sudden, he recalled.

"I remember how very little rain fell. But I remember the wind being the strongest force of nature I've ever witnessed and probably the scariest sounds I've ever heard in my life," he said.

Utility poles were down all over the island, and his 7th-grade classes were held in Army tents for several months.