Planning a road trip this holiday weekend? July Fourth travelers in South Carolina could face heavy traffic, more expensive gas and bad weather on their way to celebrating with fireworks, parades and cookouts.

Going 4th

610,500 S.C. residents are expected to travel more than 50 miles from home this weekend. Most will drive. About 128,300 will go by plane, train, bus or ship.

Top July 4th destinations in the region: Charlotte, Myrtle Beach, Charleston, Wilmington and Nashville.

Average gas: $3.33 in S.C.; $3.58 in Ga.; $3.56 in N.C.

Lodging: On average, hotel rates are up 15% from last year at AAA Two Diamond hotels and up 9% at AAA Three Diamond properties.

Caution: S.C. Highway Patrol's "Operation Life" campaign targeting drunk drivers runs July 1-31.

AAA Carolinas

Nearly a half-million South Carolinians, about 10 percent of the population, are expected to hit the road this weekend for holiday vacations, according to a survey from AAA Carolinas.

That's the highest number of drivers the agency has expected over the holiday weekend in the past 13 years.

"The economy is improving and confidence is up, so more people feel like they can travel without as much risk," said Tom Crosby, spokesman for AAA Carolinas. "Also, after the harsh winter, this is really the first vacation that a working parent may be able to take with their kids."

The Charlotte-based travel club estimated that 41 million Americans will travel at least 50 miles or more. That's up from the 40.3 million who traveled during last year's Independence Day weekend.

The calendar is helping to push up the number of vacationers. The holiday falls on a Friday this year, making it an easy three-day weekend for many travelers.

As usual, the vast majority of road-trippers will be going by automobile: 85 percent.

And fueling up for the trip won't come as cheap, with the state's average gas price at a six-year high at $3.33 per gallon. Although gas in South Carolina is 21 cents more expensive than last year, the report says it's still the cheapest gas motorists will find across the country. The national average is $3.67, according to AAA.

Fuel prices usually decline this time of year when refineries increase supplies for the surge of summer drivers, but costs have been climbing recently after the conflict in Iraq broke out last month, AAA says in the report.

Those patriotic travel plans may be interrupted by inclement weather if Tropical Storm Arthur stays on its track toward the Southeast coast. Meteorologists with the National Hurricane Center predicted Tuesday the storm would be to the east of Charleston by Thursday, which could cause strong winds and heavy rain as it moves north offshore.

Although weather in the Lowcountry likely will be back to normal by the holiday on Friday, forecasters said the storm is expected to reach hurricane strength by the time it reaches North Carolina's Outer Banks early on Independence Day.

"Needless to say, weather enters into the enjoyment of the July 4th weekend, and travelers need to continue to monitor weather forecasts," Crosby said.

The Associated Press contributed to this report.

Reach Abigail Darlington at 937-5906 and follow her on Twitter @A_Big_Gail