Authorities are scrambling to prepare the Big Island and windward Maui for Tropical Storm Calvin as the system moved closer to making landfall Tuesday.

The Central Pacific Hurricane Center has issued a tropical storm warning for Hawaii County, advising residents and visitors to be aware of high winds, dangerous surf and flash flooding. The rest of the state was urged to monitor the storm’s progress for updates.

The National Weather Service said Tuesday that Calvin could bring several inches of rain to Hawaii island in a short period of time, primarily along the windward slopes and southeastern flank. Rainfall amounts of 3 to 6 inches were forecast for windward Maui, and 2 to 4 inches were expected elsewhere in the state.

As of late Tuesday afternoon, the NWS was forecasting gusty and potentially damaging winds, possibly across the state. Power outages and downed trees are possible over the next day.

People in Hawaii have been warned for days to assemble emergency kits, secure loose outdoor items and to monitor weather conditions through official channels.

Additional emergency shelters on the Big Island opened on Tuesday afternoon to accommodate those needing refuge during the storm.

The shelters, which allow pets, include Pahoa High School, Hilo High School, Keaau Armory, Robert Herkes Gymnasium in Pahala, Naalehu Community Center, Honokaa High School, Hisaoka Gymnasium in Kohala, and Waimea Elementary School. Pet owners must bring carriers, food and other animal supplies. 

State offices and all Department of Education schools on the Big Island are closed Wednesday due to weather conditions.

Access to Waipio Valley Road is limited to access by residents and farmers only to ease evacuations if needed, according to a county news release.

The Hilo and Kona airports remain fully operational as are the Hilo and Kawaihae harbors, according to the state Department of Transportation.

The Hawaii Tourism Authority is advising travelers to check with their airline for flight delays or cancellations and to check on flight status before going to the airport.

The Hawaii County Council’s Wednesday meeting has been rescheduled for July 26.

Calvin will likely weaken into a Tropical Depression by Thursday, according to the National Weather Service.

Gov. Josh Green signed an emergency proclamation to make resources available in the event of storm impacts.