Island this morning. Maui and Oahu will see similar conditions as early as Thursday.

"Life threatening impacts are likely" to hit Hawaii, regardless of whether the storm makes landfall, NWS said in a statement.

Authorities warned residents of major flash flooding, landslides and mudslides, "even in areas not usually prone to flooding". Forecasts predict more than 20 inches (50cm) of rainfall.

Rip currents, rough surf, and waterspouts are also concerns along the coasts, particularly on the right side of the storm.

Governor David Ige signed an emergency proclamation ahead of Lane's onset, as "the danger of disaster is of such magnitude to warrant pre-emptive and protective action".

On Twitter, he urged residents to prepare for the storm and said he had "never seen such dramatic changes in the forecast track as with HurricaneLane".

Image copyright Reuters Image caption Honolulu residents stock up on gas and essentials as Hurricane Lane approaches

Lisa Bucci, a scientist with the National Oceanic and Atmospheric Administration (NOAA), shared a video of Hurricane Lane from a research plane, noting: "It's a strong and dangerous storm."

In the state's history, only two storms of this strength have ever come within 350 miles (563 km) of the islands, according to the NWS.

Hurricanes rarely hit the Central Pacific region, due to currents and water conditions. These storms have always been more common in the eastern US.

According to NWS, only four named storms have made landfall in Hawaii since 1959 - and only two of those storms were hurricanes.

Image copyright Getty Images

Hawaii generally sees about one storm strong enough to earn a name