MIAMI - Forecasters say Tropical Storm Danny weakened in the Atlantic and is barely a tropical storm.However, a tropical storm warning for the coast of North Carolina remains in effect Friday morning. Danny Large waves are expected to produce dangerous waves and deadly rip currents along the U.S. East Coast over the next two days.Danny Maximum sustained winds have decreased to near 40 mph (65 kph).The storm is centered about 400 miles (640 kilometers) south of Cape Hatteras, North Carolina, and north-northwest at 9 mph (15 kph). In turn, to the north with an increase in speed expected later in the day.