The cooler weather is in the air (at least here in Chicago), fall is coming, and summer spec gasoline is fading. All of which means the return of winter spec gasoline, and with it, spot gasoline prices are trading far lower this morning.

Spot gasoline prices are the prices that influence wholesale gasoline prices, which is the price that stations pay when filling their underground tanks. The fact that spot is down this morning is likely thanks to the changing of the guard- or in layman's terms, EPA's clean burning summer gasoline requirements were over as of September 15, and less expensive to make winter gasoline is returning.

So far this morning, all regions are looking at spot prices lower than last week, and that's a good thing for motorists and bodes well for retail prices to drop. Depending on region, prices are down 5-16 cents per gallon at this writing, which is subject to change until the market "settles" or closes this afternoon.

What's it mean for motorists? Well, with spot prices down, it'll eventually mean lower gas prices at the pump too. Gas stations will be eventually be lowering prices if the market closes lower. More importantly, the return of winter gasoline means the summer driving season is really over, as we've already witnessed by looking at paltry demand data from the Department of Energy.

By Halloween, the national average easily could be five to fifteen cents per gallon lower, and a few areas will likely flirt with sub-$3 gasoline.