The official start of summer is less than week away, and you're probably dreaming about your summer vacation already. But there's more to vacations than just enjoying some time away. By tapping into vacation trends, you can spot profitable investing opportunities.

No matter what the economy is like, you can count on one thing: People will figure out how to make the most of whatever time they can take off. Looking at what they're most likely to do can uncover some ways you can make money -- and there's nothing better than taking a vacation with profits you earned by making smart investments.

Staying close to home
During the go-go years of the economic boom, luxury vacations were all the rage. All it took was a home-equity loan to afford whatever you wanted to do, as companies such as Las Vegas Sands (NYSE: LVS) built ever-more opulent casino resorts to woo would-be travelers.

But during the recession, high-cost vacations gave way to so-called "staycations" -- effectively, staying close to home, living in your own house rather than getting a hotel, and taking advantage of free or cheap things to do around town. That trend was responsible for a lot of pain in the industry, with Las Vegas Sands going from a profit of $117 million in 2007 to a loss of $355 million in 2009.

Now, though, vacationers are ready to get out of town. But at least if current trends hold up, they're probably not going to go far.

Hitting the road
A number of surveys have looked at likely travel behavior for the coming summer months. Here's a quick summary of some of their findings:

  • Nearly six out of 10 Americans plan to take a trip this summer, up from just over half last year.
  • People aren't planning to go very far, though. Only 20% will get to U.S. destinations by air this year, and only 14% plan to go overseas.
  • Based on sales of camping equipment, it looks as though demand for camping trips is on the rise.

If those trends persist, you'll find some clear winners and losers.

Winner: theme parks
When it comes to a family-friendly vacation without going too far from home, amusement parks are a logical choice. With Cedar Fair (NYSE: FUN) and Six Flags having locations around the country, you don't need to rely on the harder-to-reach Disney (NYSE: DIS) theme parks for family fun.

Last month, Six Flags reported promising results and better-than-expected sales even during the industry's typical offseason. If those trends hold up, investors could find themselves rooting for long lines instead of suffering through them.

Winner: outdoors retailers
When camping gets popular, it's good news for the companies that produce and sell camping gear. Such stocks include bootmaker Timberland (NYSE: TBL), which has already seen substantial sales growth in the past year. Similarly, retailer Cabela's (NYSE: CAB) caters to hunting, fishing, and camping fans, and the company has posted good results lately despite falling short of lofty investor expectations.

Loser: airlines
With air travel down, airlines could well see their recoveries come to a standstill. Delta Air Lines (NYSE: DAL) topped the list of companies collecting the most in baggage fees from customers in 2010, approaching the $1 billion mark. Extra money from fees has helped many airlines stay profitable despite high fuel costs and the impact of the recession.

But higher air fares are taking their toll on summer traveler demand. Even Southwest Airlines (NYSE: LUV) is starting to lose its former status as the king of discounters, with average ticket prices rising nearly 40% in the past five years. If fares don't show some relief soon, any chance of salvaging the summer season could disappear.

Have fun!
Of course, it's important to remember that in the long run for these businesses, a single three-month season isn't going to make a huge difference. Nevertheless, by spotting trends ahead of the investing masses, you'll at least be better prepared to hear good news from those companies that see the most benefit -- as well as the inevitable excuses from those that fall short.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.