According to the monthly WEX Inc. fuel report, retail gas prices have reached their highest levels since October, rising by more than 25 cents since the beginning of the year.

At right are monthly average prices per gallon by city.

WEX said that the highest national retail average seen in the month of January hit $3.53.

There are several reasons, WEX said, for the early price increases, noting that we're at the beginning period of moving from summer fuel blends to winter blends, which has inched prices higher. Most regions of the country fully make the switch in late February or March.

On the West Coast, however, wholesale gasoline prices went up by more than 50 cents per gallon in January. WEX cites that this is largely because refineries have already made the switch to summer gasoline in this part of the country.

In regards to imports, WEX said that imported gasoline from Europe is down this year, adding that U.S. refineries have been offering cheaper crude and natural gas, allowing more gasoline to be refined in the U.S. for the East Coast region. According to the report, it's likely that European refineries cannot make a profit on East Coast gasoline sales, and may not be able to for the "foreseeable future."

As more parts of the country switch to summer blend gasoline, WEX said prices are anticipated to go higher, with some analysts predicting a retail national average as high as $3.90 per gallon. However, some experts predict that demand for gasoline will soften this year — helping to weigh down the prices — and that we could see demand levels similar to 2002.

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