SAN JUAN, Puerto Rico (AP) — Tropical Storm Bertha swirled toward the Caribbean on Friday as islands in the eastern region prepared for heavy rains and strong winds.

The storm's maximum sustained winds Friday morning were near 45 mph (75 kph), with no significant change in strength expected in the next two days. Bertha was centered about 110 miles (175 kilometers) east-northeast of Barbados and was moving west-northwest at 20 mph (31 kph).

The storm was expected to pass near or north of Barbados Friday afternoon, according to the U.S. National Hurricane Center in Miami.

Tropical storm warnings have been issued for Barbados, St. Lucia, Dominica, Martinique, the U.S. and British Virgin Islands and Puerto Rico. A tropical storm watch is in effect for St. Vincent and the Grenadines.

Bertha is expected to generate up to 3 inches (8 centimeters) of rain across the region, with isolated amounts of up to 6 inches (15 centimeters) in certain areas.