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​Ana becomes tropical storm as it nears Carolinas

Early surprise Ana muscled up to a tropical storm early Saturday as it plodded ever closer to the Carolinas, threatening to push dangerous surf and drenching rains against the Southeast coast as it made its appearance weeks ahead of the official start of the Atlantic hurricane season.

Universities along the coasts of North Carolina and South Carolina were keeping an eye Saturday on Tropical Storm Ana as they held graduation ceremonies. Coastal Carolina University in Conway, South Carolina, moved its commencement Saturday from Brooks Stadium indoors to its student recreation center as part of a weather plan.

Officials in surrounding Horry County said they were in discussion with the National Weather Service and state officials but have not opened the county emergency management center.

In Wilmington, North Carolina, UNC Wilmington was able to hold its commencement as planned indoors but urged students and family to keep an eye on the school's webpage as they make their travel plans. It was cloudy in Wilmington Saturday morning.

"If travel conditions change, graduates and their guests should make their own determination whether it is safe to travel," the school said in a statement on its website.

At 5 p.m. ET Ana was centered about 65 miles south-southeast of Myrtle Beach, South Carolina, and had top sustained winds of 60 mph, the U.S. National Hurricane Center in Miami reported. The storm was moving northwest at 3 mph.

A turn toward the north and north-northeast with a gradual increase in forward speed is expected over the next 48 hours, the weather service said.

Ana was threatening to bring dangerous surf and drenching rains to the Carolinas over the weekend. Tropical storm conditions could reach the coast by later Saturday, and the center of the storm could come ashore early Sunday.

The North Myrtle Beach Department of Public Safety announced Saturday that no swimming in the ocean was allowed because of the weather.

New Hanover County, North Carolina, officials warned people who were thinking about coming to the beach over the weekend.

"Beachgoers are encouraged to use extreme caution this weekend," said Warren Lee, Director of New Hanover County Emergency Management. "With the elevated risk of rip currents, the best advice is to stay out of the water when the risk for rip currents is the highest and comply with any advisories given by lifeguards."

Senior Hurricane Specialist Stacy Stewart said dangerous surf and rip tides appear to be the biggest threat posed by the Atlantic season's first tropical storm though isolated flooding in some coastal areas is also a concern. Although the season doesn't formally start until June 1, he told The Associated Press such early surprise storms are not all that unusual every few years or so.

"We had a similar situation occur twice back in 2012 when we had two early season tropical storms, Alberto and Beryl," Stewart noted of two storms that also emerged in the month of May. "That was very unusual to get two storms before the normal start of the hurricane season; one is not that unusual."

But Ana marked the earliest subtropical or tropical storm to form in the Atlantic since another storm named Ana emerged in 2003, the Hurricane Center said in an earlier tweet. The Atlantic season officially runs from June 1 to Nov. 30, a period experts consider the most likely for tropical activity in the ocean basin.

Stewart said Ana emerged from a subtropical system, meaning it initially had characteristics of both a tropical storm -- which draws energy from warm ocean waters -- and a traditional storm system driven by temperature changes typical of cooler weather before the season start.

Despite Ana's early appearance, he cautioned, swimmers and surfers should stay out of the water because of rough surf and dangerous rip tides. He added people watching the surf from jetties and piers should be cautious due to waves the storm can kick up.

"The biggest danger is rough surf and rip currents. We just don't want people out there swimming in the waters. We especially don't want surfers in the rough surf. If they go under they could get dragged out to sea," Stewart added.

The center said a tropical storm warning extends from south Santee River in South Carolina to Cape Lookout, North Carolina, with 2 to 4 inches of rain expected over a wide area and up to 6 inches in some isolated spots. The storm could push water 1 to 2 feet above normal height levels, causing some localized flooding.

A tropical storm watch also was in effect for Edisto Beach, South Carolina, to south of the South Santee River.

A tropical storm warning means tropical storm conditions are expected somewhere within the warning area, in Ana's case within 12 to 24 hours, according to the center. A tropical storm watch means tropical storm conditions are possible in the watch area within 24 hours.

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