Even if summer is the last thing on your mind these days, rest assured that the businesses banking on a robust travel season are already fretting over the obvious. Gas prices keep climbing, and that's bad news all around. Last week, most of the major airlines raised their fares by $10 to help offset the rising cost of jet fuel. When American Airlines' parent, AMR (NYSE:AMR) -- a company already losing a whole lot of money -- announces that it will have to shell out an additional $1.4 billion to cover fuel increases this year, you begin to grasp the severity of the situation.

Will the airlines be able to stick to their higher fares? It's a financial necessity, but price wars make companies do silly, silly things. In the end, the costs of consumer vacations are inching higher for those traveling by air.

But what about the traditional road trip? Well, prices at the pump will have a definite impact there. They have already created a shift in the automotive industry, where truck and SUV powerhouses like Ford (NYSE:F) and General Motors (NYSE:GM) are seeing drivers trade down to smaller and more fuel-efficient cars.

Gas prices have risen by more than $0.20 a gallon over the past month. Fuel costs may be just a small part of any vacation budget, but those costs might really add up if the pumps are still pricey in a few months.

If the perception exists that fuel prices will keep inching higher, it may weigh heavy on the minds of those planning long summer vacations. That would certainly be bad news for everyone from hotel chains like Hilton (NYSE:HLT) to theme parks like Disney's (NYSE:DIS). While the argument that folks will simply stay closer to home may be good news for regional amusement park operators like Six Flags (NYSE:PKS) or all-inclusive resorts like Great Wolf (NASDAQ:WOLF), there are few givens in the travel space until the guests have checked in.

Now for some more summer reading:

Longtime Fool contributor Rick Munarriz will be staying in his home state of Florida for his family's summer vacation this year. He won't necessarily find things any cheaper at the pumps, though, since Florida is a pretty big state. He owns shares in Disney and Great Wolf Resorts. The Fool has a disclosure policy. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early.