Southwest Michigan has the state’s lowest gas prices to start the week. According to the latest survey from Triple-A Michigan, the Benton Harbor-St. Joseph average is up nearly 15¢ from last week at $2.38. The statewide average rose 13¢ to $2.42, which is the third-largest jump in the country. The state’s most expensive gas is being sold in Jackson at $2.48 a gallon. GasBuddy spotters note Niles has the lowest prices in the state at $2.03, and South Haven’s prices range from $2.29 to $2.32 a gallon.