I don’t know if any Memorial Day events or parades for that area. If you haven’t attended the annual Steam up event in Brooks Oregon, about a forty five minute drive from Portland area (depending on what part you are in, how fast your vehicle travels and traffic) the event happens the last weekend of July and again the first weekend of August. The first weekend is a vintage tractor show, parade, pulls, swap meet, etc. The second weekend is the military appreciation weekend that includes an MV show area as well as the vehicles being included in the parade. There’s a great club group that participates in the event and a great opportunity to join the club, they also participate in additional local events during the year.