After a sudden surge, gas prices are beginning to level off.

Area gas prices hit a three-year high of $4.30 per gallon on March 10, but have since fallen to $4.21 per gallon, according to gas price tracking website GasBuddy.com. Those prices are still more than 70 cents per gallon higher than at the start of 2012, but remain below the all-time high of $4.52 per gallon, reached in 2008.

"The national average has finally showed some signs of slowing down, and gasoline prices in dozens of areas have virtually stabilized after rising for two to three consecutive weeks," said GasBuddy.com Senior Petroleum Analyst Patrick DeHaan. "The rally in gasoline prices started in March, we could have dubbed it March Madness, to coincide with the flurry of college basketball games, but as the tournament winds down, gasoline prices too have slowed their increase, and maybe — just maybe — gasoline prices are closer to a peak than we initially expected."

The seeming leveling-off of gas prices led DeHaan to revise 2012 forecasts downward despite continued market uncertainty over instability in Iran.

Nationally, gas prices sit at $3.89 per gallon. DeHaan expects that national average to peak at $4.23 in May, gradually declining to $3.54 per gallon in December.

San Francisco gas prices – the nearest area forecasted specifically by GasBuddy.com – are projected between $4.25 per gallon and $4.60 per gallon on Memorial Day.

Drivers can expect a temporary near-term surge, too, as refineries switch over to producing cleaner-burning summer gasoline, reducing supply levels.

“While the 2012 outlook isn’t what I’d call rosy, we can look to Europe at their $6-$9/gallon gasoline and be happy that we’re still not paying as much as some countries,” DeHaan said. “… Motorists who drive a SUV may want to consider calling their banking institution and obtain a credit limit expense so they can afford this summer’s fuel expenses.”

A gallon of regular unleaded gasoline can be found as inexpensively as $4.05 per gallon in Turlock, as of Tuesday.