MIAMI (AP) — Tropical Storm Bertha has formed, becoming the second named storm of the Atlantic hurricane season.

The U.S. Hurricane Center in Miami said the tropical storm’s maximum sustained winds Thursday night were near 45 mph (75 kph).

The storm is centered about 275 miles (445 kilometers) southeast of Barbados and about 385 miles (620 kilometers) southeast of St. Lucia, and is moving northwest at 20 mph (31 kph).

A tropical storm warning has been issued for Barbados and Dominica. A tropical storm watch has been issued for Puerto Rico and the U.S. Virgin Islands.

Bertha was expected to pass near Barbados on Friday afternoon and travel through the central Lesser Antilles on Friday evening.

The hurricane center said little change is expected in the storm’s strength over the next couple of days.

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