The conversion to summer-blend gasoline, statewide refinery issues, and a rise in crude oil prices have sent California prices to new highs, according to the latest AAA Northern California monthly gas survey.

Many metro areas in Northern California saw an increase of at least 31 cents per gallon over the past month.

California’s average price for a gallon of regular unleaded gasoline is $4.06, up 45 cents since last month’s AAA report on January 8, 2013.

For perspective, gas prices today are 22 cents more expensive than California’s average price on this date last year.

Among all 50 states, California has the second highest state average price for regular, unleaded gasoline. Hawaii is the highest at $4.24.

“The price of gasoline in California rose above $4.00 per gallon on Friday, marking the first time since November 3, 2012, when California was last above this level, that a state average in the continental U.S. has exceeded this threshold.” said Cynthia Harris, AAA Northern California spokesperson.

Northern California gas prices are now averaging $3.95, a change of 39 cents in price from last month’s report.

In the San Francisco Bay Area, motorists can expect to pay an average price of $4.03, which is up 35 cents from last month.

The California state average price of $4.06 is up 45 cents, which is 46 cents more than the national price of unleaded regular gasoline, $3.60.

In the first 90 days of 2012, geopolitical tensions with Iran pressured the national price at the pump almost 65 cents higher.

The beginning of 2013 does not have a similar situation that is moving the market. Unlike recent years (Libya in 2011 and Iran in 2012), escalating geopolitical tensions overseas have not been a major contributing factor to the early-year price increase. AAA expects that the increases to the national average will slow as temporary production concerns are addressed.

In the Northeast, reports surfaced of long lines at the pump as drivers filled up their cars in advance of winter storm “Nemo,” which blanketed much of the Northeast with snow over the weekend. However the ultimate short-term impact on regional retail prices was minimal as expected.

The ultimate impact of the storm is likely to push back demand for gas, as the snow continues to keep drivers off of the road in the densely populated Northeast.

After declining slightly to end last week, West Texas Intermediate (WTI) prices again moved up today settling $1.31 higher at $97.03 per barrel at the close of formal trading on the NYMEX.

The least expensive average price in Northern California can be found in Modesto, where regular is $3.84 per gallon. Of all the metro areas in Northern California, where gas prices are tracked by AAA, Eureka has the highest average price at $4.15. The highest price of gasoline in the nation’s metro areas is in Hilo, Hawaii, at $4.26 per gallon.