Radar and Hurricane Hunter data show that Arthur is slowly strengthening and is expected to become a hurricane on Thursday.
With wind shear diminishing above and waters below very warm, additional strengthening is likely, according to Chief Meteorologist Ed Piotrowski.
He says most of the intensity forecast models show this system becoming a hurricane Thursday.
Tuesday morning The National Hurricane Center upgraded Tropical Depression #1 to Tropical Storm Arthur.
As of 11am Tuesday, T.S. Arthur had maximum sustained winds of 40 mph with higher gusts and is slowly moving Northwest at 2 mph.
Horry County moved into Operating Condition Level 4 (OPCON 4) in preparation for the storm, according to a news release sent Monday.
"OPCON 4 puts Horry County on "Alert" status, which means that county officials have begun discussions with South Carolina Emergency Management, the National Weather Service, and other coastal communities," according to the release.
The Horry County Emergency Operations Center (EOC) is not active.
Georgetown County government also moved to OPCON 4 at 2 p.m. Tuesday. They are also operating on an "Alert" status and have not made the Georgetown County Emergency Operations Center active.
A tropical-storm watch was in effect Tuesday morning for the east coast of Florida from Fort Pierce northward to just south of Flagler Beach.
Piotrowski says we can expect any impacts from this system Thursday into Thursday night, although rip currents may become a problem as early as Wednesday.
Read his thoughts on his WPDE Tropical Update Blog here.
Additional hurricane information can be found on Horry County Emergency Management's website.