Cuba not only exhibits places of tourist interest but also offers plenty of historic spots. You should dress casually during the day, especially if you are walking around the city. Although these showers are short lived, they are relatively intense. Bring and umbrella if you intend to walk around at this time of the day in these months.
Toiletries are exorbitantly expensive here.
Try and bring enough shampoo, shaving foam and blades, deodorant, etc. Also, film, batteries and video cassettes are very expensive and it worthwhile bringing a good supply. Always drink bottled or boiled water. Cuban's are deceivingly immune to the microbes that will make you sick. It is advisable to bring some formal clothes for concerts, restaurants, ballet and other evenings out that require elegance.