Hurricane Lane strengthens to a maximum Category 5 cyclone as it bears down on Hawaii

Hawaii is on high alert as Hurricane Lane has strengthened to a maximum Category 5 cyclone and is forecast to bear down on the islands bringing storm-force winds, heavy rain and dangerous waves.

Residents have been stockpiling food and water, and schools and public sector jobs have been suspended.

Official warnings have been issued for Hawaii and Maui counties, in the eastern part of the islands, where the first dangerous gusts could hit on Thursday.

As of Wednesday morning, the hurricane is about 500 miles (804 kilometres) southeast of Honolulu.

The US National Weather Service said data from their aircraft indicate maximum sustained winds have increased to near 160mph (260km/h) with higher gusts, upgrading Lane from a Category 4 to a Category 5 storm.

Hurricane-force winds extend outward up to 40 miles (65km) from the centre and tropical-storm-force winds extend outward up to 140 miles (220km), the service said.

The storm “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 Centre warned as Lane tracked closer to the state.

The storm had been moving west, but it is expected to turn northwest toward Hawaii on Wednesday.

There remains uncertainty as to whether the hurricane’s path will move to the north or south, meteorologist Gavin Shigesato said, adding: “It’s still a very strong storm.”

"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 said.

But even if the eye of the hurricane does not hit Hawaii directly, the huge weather system will likely move very close to the islands between Thursday and Saturday.

In this scenario, Hawaii could still be battered by devastating gusts and significant rainfall, the hurricane centre said.

The latest bulletin from the National Weather Service said in addition to high winds, the heavy rain could affect portions of the Hawaiian Islands from late Wednesday into the weekend, leading to flash flooding and landslides.

“Lane is expected to produce total rain accumulations of 10 to 15 inches with isolated amounts greater than 20 inches over the Hawaiian Islands,” the service said.

In addition, residents can expect dangerous conditions on the coast, though with less dangerous conditions on north-facing shores.

The service said: “Large swells generated by Lane will impact the Hawaiian Islands, beginning tonight on the Big Island, spreading across the remainder of the island chain on Wednesday. These swells will produce large and potentially damaging surf along exposed west, south and east facing shorelines.”

Hurricane Lane comes just two weeks after Hurricane Hector prompted the mayor of Hawaii county to declare a state of emergency, but the eye of the storm eventually swept past the islands to the south.

Agencies contributed to this report