Hank Silverberg, wtop.com

WASHINGTON – If your gas tank is near empty this weekend, you might want to wait until Monday to fill it up.

Gas stations will convert from the summer blend of gasoline to winter blend Sept. 15. When that conversion takes place, supply will increase and prices will drop, according to Tom Kloza, chief analyst for the Oil Price Information Service.

“Between this weekend and Thanksgiving day, we should see a much more palatable price drop,” he says.

That drop could be between 25 and 50 cents a gallon.

Gas prices nationally could average about $3.25 by December unless there is some kind of disruption in production like hurricane damage to Gulf Coast refineries.

“We’ve got high crude prices,” Kloza says. “We will see some price drops, but we are dropping from numbers at Labor Day that are higher than we have ever seen.”

AAA says the average price of unleaded gasoline in the D.C. metro region was $3.77 this week, which is down a penny from the week before.

Gas was $3.61 per gallon this time last year.

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