First 2016 U.S. tropical storm warning issued for South Carolina

A tropical storm warning, the year's first for the United States, was issued on Friday by the National Weather Service for the coast of South Carolina, five days before the official start of the Atlantic hurricane season.

The bulletin, posted by the weather service's National Hurricane Center in Miami, warned of tropical storm conditions within 36 hours along coastal South Carolina from the Savannah River north to the Little River Inlet.

Tropical storms are defined as a cyclonic weather systems packing winds with sustained surface speeds ranging from 39 to 73 miles per hour (63 to 119 kilometers per hour).

The current threat to South Carolina was posed by the formation of a tropical depression off the southeastern United States, marking the second such weather system of 2016, following one that grew into Hurricane Alex in the far eastern Atlantic in January, according to the Hurricane Center.

Alex, a rare wintertime storm that threatened the Azores island group far off the coast of Portugal, never came near the United States.

If the latest tropical depression strengthens into a tropical storm, it would be named Bonnie, and by next Wednesday would rank as the first of the 2016 Atlantic hurricane season, which officially runs from June 1 to through Nov. 30.

Some strengthening of what is now designated Tropical Depression Two is forecast during the next 48 hours, with the depression expected to grow into a tropical storm on Friday night or on Saturday, the Hurricane Center said.

The center of the latest depression, with maximum sustained winds of 35 mph (55 kph), was located near latitude 28.5 North, longitude 74.7 West, the Hurricane Center said.