Deauville's season is short and intense. July and August are when the resort is in full swing: races at La Touques, the boardwalk packed, every restaurant booked. The American Film Festival in the first half of September draws a different crowd — film and media — and the weather is often the most pleasant of the year.
May and June are a quieter alternative, with reliable weather and many of the hotels and restaurants already open. October and November can be beautiful but most things close down. Winter is genuinely closed; many of the resort businesses shut completely from November to March. The seafront and the boardwalk remain accessible year-round, and the long beach walks in clear winter weather are spectacular.