Bridgetown, Barbados - Much of the southeast Caribbean was on alert Sunday as Beryl strengthened into the first hurricane of the 2024 Atlantic season, with forecasters warning it will swiftly become a major storm.

The US National Hurricane Center (NHC) said Beryl – currently churning in the Atlantic Ocean about 530 miles east of Barbados – was expected to bring "life-threatening winds and storm surge" when it reached the Windward Islands early Monday.

Warning the storm was "getting stronger," the NHC forecast it would become a "dangerous major hurricane" by the time it hit Caribbean communities.

Barbados, St. Lucia, St. Vincent and the Grenadines, and Grenada were all under hurricane warnings, while tropical storm warnings or watches were in effect for Martinique, Tobago, and Dominica, the NHC said in its latest advisory.

Cars were seen lined up at gas stations in the Barbadian capital Bridgetown, while supermarkets and grocery stores were crowded with shoppers buying food, water, and other supplies. Some households were already boarding up their properties.

A major hurricane is considered a Category 3 or higher on the Saffir-Simpson scale, with winds of at least 111 miles per hour.

Such a powerful storm forming this early in the Atlantic hurricane season – which runs from early June to late November – is extremely rare, experts said.

"Only five major (Category 3+) hurricanes have been recorded in the Atlantic before the first week of July. Beryl would be the sixth and earliest this far east in the tropical Atlantic," hurricane expert Michael Lowry posted on social media platform X.

The NHC said that as of 2:00 AM Sunday, Beryl's maximum sustained winds had increased to nearly 90 mph with higher gusts.

"Hurricane conditions are expected in the hurricane warning area beginning early on Monday," it said, warning of heavy rain, flooding and storm surge that could raise water levels as much as seven feet above normal.

"Devastating wind damage is expected where the eyewall of Beryl moves through portions of the Windward Islands," the NHC said, indicating wind speeds in some locations could be 30% stronger than those listed in their advisory.

The Saffir-Simpson wind scale designates Category 1 hurricanes as having wind speeds of at least 74 mph, up to Category 5 storms with winds of 157 mph or higher.

The US National Oceanic and Atmospheric Administration said in late May that it expects this year to be an "extraordinary" hurricane season with up to seven storms of Category 3 or higher.

The agency cited warm Atlantic ocean temperatures and conditions related to the weather phenomenon La Nina in the Pacific for the expected increase in storms.

Extreme weather events including hurricanes have become more frequent and more devastating in recent years as a result of climate change.