It's a SoCal thing. Those not from SoCal probably wouldn't understand.
Dapper Day at Disneyland happens several times per year, but there's always one in September. I've heard they tried one at WDW this year, but not many people showed up and the Midwest and East Coast tourists at WDW in their schleppy WalMart jorts and oversized t-shirts definitely don't get it and definitely aren't Dapper. Somethings, like Dapper Day, are meant only to work at Disneyland.
Dapper Day 101: SoCal locals, mostly in their 20's and 30's, dress up to the nines and go to Disneyland for the day. Everyone walks around in their very finest, and promenades and parades throughout the park and checks out everyone else in their very finest. It's not a day to get soaked on Splash Mountain or muss up your hair on California Screamin', rather it's a day to elegantly lean against the railing on the deck of the Mark Twain or sit politely in the Tiki Room and enjoy the park as Walt designed it to be enjoyed.
In the evening the Dapper kids go dancing in Disneyland, or go drinking at Carthay Circle in DCA. Or both. Everyone looks fabulous, that's a rule.
As per the SoCal youngsters of the mid 2010's, they generally wear vintage clothing or vintage inspired looks from the 1950's and 60's. Gentlemen wear suits or sport coats or vests with pocket squares and shiny shoes and pressed trousers and sleek haircuts. Ladies wear fancy frocks and poofy dresses with heels and elaborate hairdos and ladylike gloves and custom made hats and absolutely perfect makeup. It's all very swanky and very fancy. Again, it's a SoCal thing for all the young locals who adore Disneyland USA (and also California Adventure).
