With cheaper, "winter-blend" gasoline slowly reaching gas pumps nationwide, gas prices have started to trend downward in Wyoming and across the county.

Nationally, the average price for a gallon of regular unleaded slipped nearly three cents to $3.77 per gallon on Sunday. Patrick DeHaan, a senior petroleum analyst with GasBuddy.com, says he expects prices to drop further in the coming weeks.

I do expect that, over the next week, we will continue to see prices slowly decreasing," DeHaan said. "Winter gasoline will be in full use over the next few weeks - it's a transitional change from summer to winter, it's not an all-at-once change."

The average price for a gallon of regular unleaded in Wyoming dropped by about two cents to $3.67 per gallon, a dime below the national average.

Laramie, Mills, Cheyenne and Casper have the state's cheapest gas, with prices near $3.50 per gallon. At around $4.00 per gallon, the state's most expensive gas can be found in near Rock Springs and Jackson.