WASHINGTON, Pa. — Gas prices are slowly starting to fall locally, and the state average now sits below $4.00 a gallon. AAA says gas here in Washington County is averaging $3.99 this week, with the average in Western Pennsylvania at $3.98. This is down from $4.01 last week, but still up from the $3.34 at this time last year. The national average fell seven cents in the past week to reach $3.71 which is a level not seen since March. Officials say the lower cost of oil is the reason for the price drop. The national average has now fell for three straight months.