Taiwan was on high alert Wednesday evening as Typhoon Gaemi, forecast to be the most powerful storm to make landfall on the island in eight years, threatened to lash it with fierce winds and several feet of rain.

Schools and businesses were shut, more than 500 flights were canceled and military drills were scrapped, the authorities said. Fewer cars were on the road than usual in the capital, Taipei, where some streets were impassable from floods. Long lines formed at some supermarkets as people stocked up on food and water.

A woman in southern Taiwan was crushed to death by a tree brought down by high winds, the authorities said on Wednesday.

Gaemi had maximum sustained winds of 144 miles per hour on Wednesday afternoon, according to the U.S. Navy’s Joint Typhoon Warning Center. That would make it a Category 4 hurricane on the five-tier wind scale that is used to measure tropical cyclones in the Atlantic Ocean.

The Taiwanese authorities upgraded Gaemi to a “severe typhoon” on Wednesday, the highest level on their three-tier scale. It was expected to be first typhoon of that intensity to make landfall on the island since 2016, said Huang Chun-hsi, a meteorologist at Taiwan’s Central Weather Administration.