It takes a while, to get the oil purchased at this price from the well to your gas tank. Normally the price you see is for the futures preceding month (Nov)

Don't forget the fact the gas station people pay attention to the news and see a jump in prices and may be apt to increase their prices quicker, and decrease them slower especially if there is limited competition (they are the only gas station on that corner or are near and expressway). Gas stations don't make much money off gas, they make money off the crap they sell inside.