Earlier this week, analysts said to expect gas prices to rise slightly during the Labor Day weekend due to Tropical Storm Gustav.

On Wednesday, oil prices climbed for a third straight day — $1.88 to $118.15 as Gustav threatened Gulf Coast energy production. Not since Hurricanes Katrina and Rita has a storm posed such a worry for refineries in the Gulf.

Concern about outages is all it takes to drive oil prices higher — and retail gas costs as well.

"Between now and Monday, it's clearly going higher," predicted Tom Kloza of the Oil Price Information Service Wednesday. He told USA Today the gas prices could rise as much as a dime a gallon over the weekend.

That was before crude prices fell to $115.59 a barrel Thursday morning, down $2.56. Natural gas prices declined even further.

The prices eased because traders were assured when the International Energy Agency, the policy adviser to 27 industrialized countries, declared it would make strategic oil stocks available if the storm caused heavy damage to Gulf plants.

As of Thursday, Gustav was still in the running to become the first storm to strike a major portion of the region's energy infrastructure since 2005. Katrina and Rita crippled more than 100 platforms, flooded refineries and caused oil and gas prices to soar.

In the last three years, oil producers and refiners have found ways to better protect their operations from serious storms. The Gulf region accounts for about a quarter of domestic oil production and 15 percent of natural gas production.

On Thursday, companies like BP, ConocoPhillips, Shell and Transocean began evacuating hundreds of workers from rigs and production platforms in the Gulf, concerned that the storm could intensify in the next several days.

We'll have to wait and see which way the wind blows in the Gulf and whether it will drive gas prices higher. The national average was $3.667 Wednesday.