​Hawaii prepares for Tropical Storm Darby

HILO, Hawaii -- The National Weather Service has issued a tropical storm warning in Hawaii for Oahu, Hawaii and Maui counties in anticipation of Tropical Storm Darby, the first storm of the hurricane season.

As of 2 p.m. local time Saturday, Darby is about 45 miles south of Hilo. It's moving west at 10 mph.

Hawaii Gov. David Ige signed an emergency proclamation as the state prepares for Darby. The pre-landfall proclamation signed Friday authorizes spending state money for disaster-related relief efforts.

Honolulu Mayor Kirk Caldwell says the island of Oahu is expected to feel the effects of the storm late Saturday.

The National Hurricane Center says the storm may bring 10 to 15 inches of rain, with some areas receiving 20 inches, possibly producing life-threatening flash floods and landslides.

Shelters are open on the islands of Hawaii, Maui, Molokai and Lanai.

A tropical storm watch is also in effect for the islands of Kauai and Niihau.