MIAMI (AP) — Tropical Storm Chantal formed off the southeast U.S. coast and was forecast to bring heavy rains to parts of the Carolinas on Saturday. Tropical storm warnings were issued for portions of the two states, the National Hurricane Center in Miami said.

At 5 p.m. EDT, the storm’s center was located about 95 miles (150 kilometers) southeast of Charleston, South Carolina, and 165 miles (270 kilometers) south-southwest of Wilmington, North Carolina. Its maximum sustained winds were clocked at 45 mph (75 kph), and it was moving north at 7 mph (11 kph).

The storm’s center was expected to move across the coast of South Carolina late Saturday or early Sunday, with some some additional strengthening forecast before landfall.

Heavy rain was forecast for the coastal plain of the Carolinas through Monday — total rainfall of 2 to 4 inches (5 to 10 centimeters), with local amounts up to 6 inches — threatening flash flooding.