Earlier this week, Iowa’s largest utility annouced natural gas prices are up 16-percent from last year. Now, Triple-A-Iowa says gasoline prices are also rising in Iowa. Motor club spokeswoman Dawn Duffy says the frigid temperatures are to blame. Duffy says the cold weather means oil refiners are turning their attention to making more home heating oil instead of gasoline, putting additional strain on the resources and making gas prices rise. Duffy says it’s a seasonal price rise and it’s not considered a surprise. The early winter was warmer than normal and kept prices down a bit longer than normal. Duffy says the gas prices are back up now though and how long they stay higher depends on how cold the weather stays. She says a stop at the nearest Iowa service station will cost a smidgen more this week.The current average price for gasoline in Iowa is a dollar-76 a gallon. A month ago, the price was a dollar-73, while a year ago it was a dollar-55. The current national average is a dollar-81, five cents higher than in Iowa. Cedar Rapids has the highest priced gas currently at a dollar-81 while Des Moines has the cheapest at a dollar-72.