Tropical storm Lala closes in, hitting Hawaii's Big Island with rain, wind

Tropical storm Lala was already whipping and soaking Hawaii's Big Island early Saturday, with forecasts saying it could strengthen into a hurricane or, at the least, bring hurricane-force winds as it approaches land.

The National Hurricane Center (NHC) issued a rare hurricane warning for the island, which hasn’t experienced a direct hurricane landfall in 155 years.

Forecasters said higher elevations could get as much as 635 millimetres of rain. That could cause life-threatening mudslides in a mountainous area where people live off the grid in improvised housing, and authorities urged them to find safe shelters quickly.

"This is an enormous storm," Gov. Josh Green said. Tropical storm force winds extended outward for as much as 350 kilometres and were expected to hit the islands of Oahu and Kauai by Sunday morning.

Destructive flooding and even wildfires kicked up by the strong winds were possible in the islands.

A hurricane warning was issued for the Big Island, and a tropical storm warning was in effect for Maui County, which includes the islands of Maui, Molokai, Lanai and Kahoolawe. A tropical storm warming was also in effect for Oahu and Kauai County, including Kauai and Niihau islands.

Even if the storm remains just shy of a hurricane as it approaches land, the NHC said wind speeds atop mountains and on the windward and leeward slopes "are often up to 30 per cent stronger than the near-surface winds" indicated in its advisory, suggesting nearly hurricane-force winds in Hawaii's higher-altitude communities.

According to a University of Hawaii atmospheric scientist’s research of newspaper accounts, a Category 3 hurricane hit the northeast corner of the island in 1871. The latest forecast has Lala striking "very close to the southern tip of the Big Island," said Vanessa Almanza, a weather service meteorologist in Honolulu.

Officials and residents braced for Lala regardless of whether Hawaii takes a direct hit. Shelters were scheduled to open, and various events were canceled.

"It doesn’t take landfall to create destruction," Almanza said, noting that a lot of the impacts are felt outside the hurricane's centre.

The NHC predicted 203 to 305 millimetres of rainfall totals across Maui and lower elevations of the Big Island, and 102 to 152 millimetres across the island chain.

It also warned that the storm could cause "life-threatening flooding and mudslides, especially in areas of steep terrain," along with a dangerous storm surge and ocean swells "likely to cause life-threatening surf and rip current conditions."

As of 5 a.m. local time in Hawaii, tropical storm Lala was located about 175 kilometres southeast of South Point, Hawaii, with maximum sustained winds of 100 km/h and was moving toward the west-northwest at 20 km/h, the hurricane centre said.

State Rep. Jeanné Kapela travelled from Honolulu to be closer to her constituents on the Big Island and urged people to remain alert.