Travelers contended with big crowds and flight delays Friday, which was expected to be the busiest day of the Memorial Day weekend. More than 4,000 U.S. flights were delayed by midafternoon on the East Coast, continuing a trend that has tested the patience of travelers all week. Thankfully, relatively few flights were canceled — fewer than 100, according to tracking data from FlightAware. There were delays on the highways, too. Along Florida’s Turnpike, Wallis Tinnie said a traffic accident and road work slowed her drive to an African American history commemoration in the Florida Panhandle, the site in 1816 of the first battle of the Seminole Wars. “But we’re comfortable with it,” the Miami woman said during a stop at Port Saint Lucie.