Attire for Festival Napa Valley events is “Napa Style” casual elegance for luncheons, dinners and concerts alike. For men: Summer weight slacks worn with collared shirt. For evening events, men typically wear a sport coat, with or without a tie as they prefer. For women: It can be warm during the day but cool at night, so bring a wrap or sweater for outdoor concerts and dinners. Practical shoes are recommended, as many events take place in outdoor settings, and hosts may invite guests to visit locations that will require walking on grass, gravel paths or uneven terrain.