Hilo is expected to feel the effects first. Heavy rain could hit the Big Island as soon as Wednesday night and residents are stocking up.
"A lot of rice, water, toilet paper," says Mike Kelley of Cost-U-Less. Kelley says the store opened early Tuesday. Lines stretched to the back of the store and it didn't take long for them to run out of bottled water. Another shipment is not expected until Thursday or even Friday, after Iselle hits.
"We always cook with butane," says Matt Okuno who was at Home Depot with a cart full of butane cans.
Darlene Furness gassed-up her car then filled large gas cans for generators.
"With two coming, one right after the other, it makes sense to be prepared," says Furness of Iselle and Tropical Storm Julio which is expected to hit the island shortly after.
"We've very vulnerable to these systems," says Hawaii County Civil Defense Administrator, Darryl Oliveira, who is glad to see people getting prepared."Our concern is the entire island." The one-two punch is expected to bring rain, wind and high surf to all parts of the Big Island.