BOSTON (SHNS) – The average price of gas dropped another 10 cents in Massachusetts this week, but low fuel inventories in the Northeast are working to keep the price at the pump here higher than the national average.

AAA Northeast said Monday that a gallon of unleaded gas is now averaging $4.06 in Massachusetts, 10 cents lower than a week ago and 42 cents lower than a month ago. But Massachusetts motorists are paying $1.01 more than a year ago ($3.05) and 21 cents more than the current national average price.

“Gas prices remain relatively high here in the northeast, where inventories are lower than in other parts of the country,” Mary Maguire, AAA Northeast’s director of public and government affairs, said. “Prices continue to fall steadily, however, and that’s good news for motorists planning their last summer driving trip over the upcoming Labor Day weekend.”

The cheapest average price in Massachusetts can be found in Franklin County ($3.839 average per gallon) and then Hampden County ($3.848 average per gallon). Nantucket and Martha’s Vineyard have the most expensive gas, averaging $5.497 and $5.136 respectively. The most expensive gas on the Bay State mainland is Suffolk County’s average price of $4.297 per gallon, AAA said.

AAA on Monday cautioned that hurricane season could disrupt the last month-plus trend of falling gas prices if tropical storms disrupt oil production in the Gulf of Mexico and impact large coastal refineries.