Hurricane Beryl, a powerful storm that made landfall Monday as a Category 4, has been barreling through the Caribbean, killing at least four people, destroying houses and snapping trees in half.

The hurricane first hit Carriacou, a small island north of Grenada, on Monday morning where it flattened the island in just half an hour, while also causing extreme damage to neighboring Petite Martinique. Rescue crews departed Grenada on Tuesday morning to deliver supplies to both islands and assess the destruction.

Carriacou is known for its coral reefs and diving spots, while people on Petite Martinique are mostly involved in fishing and boat building. The two islands have a combined population of roughly 6,000, according to government data.

Late Monday, Beryl strengthened to a Category 5 and was heading west toward Jamaica.

The storm was an anomaly in what has already been an unusually busy storm season, which extends until the end of November. When it developed into a Category 4 storm on Sunday, it was the third major hurricane ever in the Atlantic Ocean in June — and the first time a Category 4 materialized this early there in the season.

The storm continued to set records, becoming the first ever Atlantic storm to grow into a Category 5 strength this early in the season, according to Philip Klotzbach, a Colorado State University meteorologist who specializes in tropical cyclones.

The storm’s rapid strengthening was a direct result of above-average sea surface temperatures, as well as a harbinger of what might be coming this hurricane season. A hurricane that intensifies faster can be more dangerous because it gives people in areas projected to be affected less time to prepare and evacuate.