Tropical Storm Lala, which formed Thursday over the Pacific Ocean, could bring extremely heavy rain, flooding and “life-threatening” surf and rip currents to the Hawaiian Islands this weekend as a hurricane, forecasters say.

Lala is expected to become a hurricane as it nears Hawaii’s Big Island, according to the National Hurricane Center.

In a worst-case scenario, Lala could pour 25 inches of rain onto the Big Island, the center said.

A hurricane warning is in effect for the Big Island and a tropical storm watch is in place for Maui County, including the islands of Maui, Lanai, Molokai and Kahoolawe.

“Hurricane conditions are expected on the Big Island of Hawaii by early Saturday (local time), with tropical storm conditions possible in Maui County by late Saturday,” the Miami-based hurricane center said, adding that wind speeds could be significantly higher in elevated areas and on the windward sides of slopes and mountains

As of late Thursday night local time, Lala was approximately 455 miles east-southeast of Hilo, Hawaii, and 670 miles east-southeast of Honolulu and was moving west-northwest at 10 mph. It had maximum sustained winds of 60 mph. A tropical storm becomes a hurricane when its maximum sustained winds reach 74 mph.

Lala is “expected to produce rainfall totals of 8 to 12 inches across Maui and the Big Island with maximum totals of 25 inches possible across the Big Island,” the hurricane center said, along with “rainfall totals of 4 to 6 inches with maximum amounts of 8 inches” across the rest of the islands. “This rainfall may produce life-threatening flooding and mudslides, especially in areas of steep terrain,” the forecasters warned.

What’s more, Lala could produce a storm surge as high as 3 feet along the coast, along with large waves and life-threatening rip current conditions.

Hawaii Gov. Josh Green declared a state of emergency Thursday anticipating Lala’s arrival. His proclamation activated potential disaster relief funds and directed “all state agencies and officers to cooperate and extend their services, materials, and facilities as may be required to assist in emergency response efforts.”

The National Park Service announced that most areas of Volcanoes National Park on the Big Island would close to visitors by Friday afternoon ahead of the storm’s arrival.