As the days grow shorter this fall, the price you pay at the gas pump coulddrop — a little. Iowa Department of Natural Resources analyst David Downingsays fall signals the end of the summer driving season and higher gasprices.Don’t expect a major drop, though, as oil-producing companies are keepinga tight control on supply.Downing says one factor OPEC can’t control is the weather. He says warmweather would require less heating oil production and an increase in gassupplies. Downing says the days of getting a gallon of gas and change backfrom a dollar aren’t likely to return.