San Diego gasoline prices on the rise at a ‘sure and steady clip’

If it seems you’re paying a little more for gasoline lately, you’re not just imagining things.

Prices at the pump have been climbing in the San Diego area, up 19.7 cents per gallon on average since Dec. 23.

And the average price for diesel fuel is poised to crack the $5 mark for the first time in more than two months.

The average price for a gallon of regular gas in San Diego stood at $4.591 on Thursday, according to AAA. Prices have increased for 15 consecutive days.

“It’s been a sure and steady clip,” said Patrick DeHaan, head of petroleum analysis at GasBuddy.

The big reason for the increase, fuel analysts say, is because California refineries are going through their annual transition from winter-blended gasoline to the state’s unique summer mixture. The summer blend’s lower-volatility formula helps reduce smog, but it’s more expensive.

The term “summer blend” is a bit of a misnomer in the Golden State because the California Air Resources Board requires gas stations in Southern California to use the less-polluting gasoline from April 1 through the end of October.<...