"Beware the ides of March."  That's what the Soothsayer famously warned Julius Caesar in Shakespeare's play.  It also sums up what travel firm AAA warned U.S. drivers about gas prices heading into this month.

"We are entering the worst time of year for visiting the gas station," AAA analyst Avery Ash said in his outlook for March gas prices.  The reason has nothing to do with price gouging, increased demand or geopolitical instability in places like Ukraine - though that certainly won't help.

It all comes down to one thing: seasonal refinery maintenance.  Yes, we're now in the time of year when refiners switch from producing the so-called winter blend to the cleaner burning summer gasoline formula.  (Or rather, formulas, since there are different blends in different parts of the country - yet another complicating factor.)

"Gas prices typically rise this time of year because many refineries cut production to conduct seasonal maintenance, which can limit gasoline supplies and cause market uncertainty," AAA said.  "This maintenance generally takes place between strong demand periods for heating oil in the winter and gasoline in the summer."  We've already seen the beginning of the price increases for this spring.

Prices are already up to around $3.20 or higher per gallon in The River Valley compared to $2.95 per gallon a month ago.