Tropical Storm Cristobal churns in the Caribbean

(CNN) -- Tropical Storm Cristobal formed early Sunday in the Caribbean, having strengthened from a tropical depression, the National Hurricane Center said.

It has maximum sustained winds of 45 mph.

The hurricane center issued tropical storm warnings on Sunday for the southeastern and central Bahamas as well as for the Turks and Caicos Islands.

Cristobal is moving to the northwest but is expected to turn to the northeast in the coming days and miss the U.S. coastline.