Tropical, beach-casual attire is the norm in Puerto Vallarta. Resort wear, boho luxe and hippie chic are common looks. Vallarta is very natural. Think peasant blouses, tunics, flowing fabric and anything ethnic.    If nightclubbing, switch to black and sleek.   For men, knee-length shorts are considered appropriate attire at all Vallarta venues. Shirts are worn untucked: polos, hawaiian and guayaberas are the fashion mode of choice. It's good to note:

• At some of the upscale dining establishments and nightclubs, long pants are more suitable.
• December through March the weather is pleasant and spring-like but nights can be chilly and breezy. The southwesterly wind from the bay shifts at night and comes down the Sierra Madre mountain range bordering the coast line. Lows can dip to the upper 50’s. You will feel the cool weather more because the architectural style of your villa is very open. Bedrooms can be closed off and have air conditioning.
• Bring long sleeves, jeans and yoga pants for the chilly air at night. If you go out on a boat, you will be glad you brought a substantial cover-up or hoodie. For exploring town and dining out, bring your pashminas and scarves, the perfect travel accessory - easy to pack and carry around while walking.
• On the other spectrum, June to October is humid and hot. Puerto Vallarta is located below the Tropic of Cancer. The sun is more intense at this latitude, humidity can be oppressive. Best to stay under an umbrella next to your pool or within steps of the ocean during the heat of the day. Light weight natural fabrics such as cotton are a must. Bring loose clothing in light colors; sleeveless tops, skirts and shorts de rigueur.
• Rainy season runs June thru October. Generally the rains don’t begin until late June, sometimes as late as the end of July. August and September is when you will see sporadic downpours and tropical storms.
• The tropical rains are actually very refreshing and help cool things off. The jungle covered mountains turn a vibrant green. It can be exhilarating to experience a thunder storm in the tropics. The sunsets are unusually intense this time of year, the atmosphere charged.
• Rains usually begin in the late afternoons or evenings, so the better part of the day is sunny. Typical with tropical climates, if it rains during the day, it will pour for 20 minutes and then the sun will come out. If you plan to do some exploring, it can’t hurt to pack a travel umbrella, a hat, sturdy shoes and clothing geared for rain when traveling to pedestrian-friendly Vallarta during rainy season.
• Comfortable shoes are imperative for walking the cobblestone streets of Vallarta, regardless of the season. High heels are for night clubbing or fine dining and only for doorstep-to-doorstep in a taxi. Cute flats will dress up your wardrobe enough at night and still allow you to navigate the cobblestones. Remember: Vallarta is very laid back and natural. You will wear your flip flops most of the time.