The average price for a gallon of gas in California rose to $5.26, up from $4.89 a month ago, but still lower than it was a year ago, according to AAA. Yahoo Finance Reporter Ines Ferre discusses the potential impact of Tropical Storm Hilary on gasoline prices in the state.

Video Transcript

JULIE HYMAN: California gasoline prices are surging past $5 a gallon with no relief in sight. The average price per gallon now sits at $5.26, that's nearly $0.40 higher than a month ago. Yahoo Finance's Ines Ferre is here with the breakdown. So what's going on, Ines?

INES FERRE: Yeah, Julie. And we know that Californians had for a while now been paying more for gas prices, compared to the national average. There's very high taxes and fees in California on gasoline. And also consumption of gasoline and diesel in California is pretty high as well.

Just to give you an idea, one out of every 10 gallons of gasoline sold in the US is consumed in California. About one out of every 15 gallons of diesel sold in the US is consumed also in California. The concern, of course, is that with the tropical storm, once hurricane Hillary, that shows up in Southern California, that that could have a potential impact on local refining and distribution systems.

Now, analysts don't expect that refineries in California would shut down because of the storm that passed throughout the weekend. But it could be impacted-- that there could be impacts by power outages and flooding conditions as well.

So if a refinery were to shut down in Southern California because of, let's say, flooding, you'd see wholesale prices, according to Andy Lipow of Lipow Oil Associates, going up by about $0.20 per gallon. And the consumer would feel it in anywhere between five to seven days.

On a national level, where gasoline prices go from here, well, that will a lot depend on the weather conditions. Of course, we are in the middle of hurricane season. And any activity that happens in the gulf and any refining capacity-- any refineries that are interrupted because of that hurricane activity can spike prices by anywhere between $0.10 and $0.20 a gallon, according to Lipow's estimates. By the way, Julie, right now, we're seeing, as you noted, the current national average for gasoline is at $3.87. It's only $0.03 away from what we saw around this time last year.

JULIE HYMAN: Oh, interesting. Well, that's right. 390 versus 387 is not that big of a difference, but people have certain perceptions when it comes to gas prices for sure. Ines Ferre, thanks a lot. Appreciate it.