The season’s fourth tropical storm, named Danny, formed off the coast of South Carolina on Monday afternoon and was expected to make landfall later this evening.
The system, which developed as a depression off the coast on Monday morning, was about 45 miles southeast of Charleston, S.C., moving west-northwest at 16 miles per hour with maximum sustained winds of 40 miles per hour, according to the National Hurricane Center. Tropical storms form when maximum sustained winds reach 39 m.p.h.
“It’s a minimal tropical storm,” said Dennis Feltgen, a spokesman for the center in Miami. “There is no such thing as a justa tropical storm. Justa is not in the dictionary so you never want to take a tropical storm lightly.”
He said the primary threat from the system was rain. Heavy rain was possible from southern coastal South Carolina and Georgia and inland across the Piedmont area of Georgia and into northeast Alabama, according to the center.
Forecasters said the system could bring one to three inches of rainfall with higher amounts along the coasts of Georgia and southern South Carolina.
“The good news is that region has been dry, so it should be able to handle the rainfall,” Mr. Feltgen said.
“Tropical-storm force winds are expected across portions of the South Carolina coast” late on Monday afternoon and evening where a tropical storm warning was in effect, the center said.
The center of the system was expected to make landfall along the coast of South Carolina on Monday evening and then rapidly weaken.
Forecasters expect that a combination of storm surge and tide will cause typically dry areas near the coast to be flooded by rising waters that will move inland from the shoreline.
Swells from the depression could also lead to life-threatening surf and rip currents.
Danny is the fourth named storm of the Atlantic hurricane season. In mid-June, Claudette was blamed for the deaths of 14 people — 10 of them children — as it moved from the Gulf Coast to the East Coast.
This was the seventh year in a row that a named storm developed in the Atlantic before the official start of the season on June 1.
Hurricanes have become increasingly dangerous and destructive with each passing season.
Researchers have found that climate change has produced storms that are more powerful and have heavier rain. The storms also have a tendency to dawdle and meander. A combination of rising seas and slower storms also make for higher and more destructive storm surges.
Scientists with the National Oceanic and Atmospheric Administration forecast that there would be 13 to 20 named storms this year, six to 10 of which would be hurricanes, and three to five major hurricanes of Category 3 or higher in the Atlantic.
Last year, there were 30 named storms, including six major hurricanes, forcing meteorologists to exhaust the alphabet for the second time and move to using Greek letters.
It was the highest number of storms on record, surpassing the 28 from 2005, and included the second-highest number of hurricanes on record.