Tropical storm warning issued for Hawaii County

JOHN BURNETT/Tribune-Herald A display at The Home Depot in Hilo Monday has waterproof flashlights and batteries, rain suits and ponchos and heavy-duty tarps, with a sign asking customers "Are you ready for the storm?"

JOHN BURNETT/Tribune-Herald A customer buys plywood Monday at The Home Deport in Hilo, as the Big Island is under a tropical storm watch with Tropical Storm Calvin approaching.

Tropical Storm Calvin advances toward the Big Island.

In a National Weather Service image from early Monday evening, Tropical Storm Calvin spin toward the Big Island.

Tropical Storm Calvin on Monday was slowly weakening as it headed toward the Big Island, but it was moving rapidly to the west at 22 mph and was expected to hit the island tonight or Wednesday morning.