(KCEN) -- Hold on to your wallets because gas prices are still on the rise.
The national average for a gallon of gas is now $3.73.
That's 43 cents more than just one month ago.
Experts blame a series of factors for the increase. Refineries are switching from winter to summer fuel, which is more expensive to produce. A refinery in New Jersey that supplies more than seven percent of the northeast's gas is closing and mid-winter maintenance has led some refineries to go offline temporarily.