Gas prices this coming Memorial Day weekend will be the highest in four years and likely start to dent the summer travel season, industry experts said. Motor club AAA reported a national average retail price of $2.93 for a gallon of regular unleaded gasoline on Tuesday, up 17.5 cents from one month ago. By AAA’s account, the average price leading up to the long holiday weekend is almost 50 cents more than the average for the last three Memorial Day weekends. “Trends are indicating that this summer is likely to bring the national average to at least $3 per gallon,” AAA spokeswoman Jeanette Casselano said in a statement . Gas prices usually follow the price for […]