Crowds watch a Fourth of July fireworks display July 4, 2009, at Caesars Palace on the Las Vegas Strip. ( Justin M. Bowen )

By Conor Shine, Las Vegas Sun and U.S. News Agency / Asian

Even though the Fourth of July falls on a Wednesday, millions of Americans are expected to hit the road next week to celebrate the holiday, with many of them heading to Las Vegas.

About 312,000 visitors are expected in Las Vegas the weekend after Independence Day, said Las Vegas Convention and Visitors Authority spokesman Jeremy Handel, a half percent increase compared to a year ago. All those visitors will have a nongaming economic impact of about $197.5 million, he said.

“Three-day weekends are always huge,” Handel said. “We’re hoping this turns into something of that nature. With the holiday on Wednesday, hopefully people will stay Thursday and Friday, too.”

Across the West, about 3 million people are expected to be traveling for the holiday, the highest amount in five years, according to AAA. The majority of residents will drive, AAA said, with lower gasoline prices helping spur people to jump behind the wheel for a weekend getaway.

However, local law enforcement agencies are warning those who plan to celebrate the holiday with alcohol to stay off the roads or risk getting pulled over.

Metro Police, Henderson Police, North Las Vegas Police and the Nevada Highway Patrol all are stepping up patrols starting this weekend to crack down on drunk driving.

Metro will be conducting sobriety checkpoints around the valley on Tuesday and Wednesday, while all agencies will collaborate on increased saturation patrols throughout the week, said Metro Traffic Bureau Sgt. Todd Raybuck.

“With the holiday falling on a Wednesday, it prolongs the activities,” Raybuck said. “We’ve started increasing our efforts this week. It will go on throughout this weekend and through July 8 in order to ensure that we can detect impaired drivers and get them off the road before they end up injuring or killing anymore of our citizens.”