Costa Rica is now a year-round destination so arguably the best time to go is whenever you can. However, there are two general seasons, a rainy season (May-October) and a dry season (November-April). September and October are usually the rainiest months. Even in the height of the rainy season though, mornings are often surprisingly clear and sunny, with clouds developing in the mid-day and soon after, rain, so when planning core activities, it’s best to plan for an early start and try to leave afternoons free for traveling or relaxing. Plus being located in the tropics means it can rain on any day of the year in Costa Rica.
The rainy season can be a better value with slightly lower prices at some hotels plus activities, parks, and beaches can be a little less crowded. Rafting is also often better during the rainy season. In addition, different areas within Costa Rica can have “micro-climates” and peak seasons for specific wildlife. For example, July-October is best for sea turtles in Tortugeuro (the most famous place to see them nesting) while in Las Baulas National Park, reached from Flamingo and Tamarindo, the best time is October-March. The best months for the beautiful resplendent quetzal are February-March-April, when they nest and the beautiful males are easy to see due to their territorial mating calls. If you have any specific interests that you feel may be helped or hurt by climate, let us know your question and we can help with advice.
Temperatures vary more by location than by time of year usually. For example, Monteverde and the cloud forests in general are cooler year-round, while the coasts tend to be hot year-round, especially mid-day. San Jose and Arenal are mid-altitude areas which are mostly pleasant year-round, though a nice rain can be welcome for cooling things off on a hot afternoon.
The Christmas/New Years time frame and Easter week are the most crowded seasons for Costa Rica, so please plan your trip in advance if you can. There are often holiday season supplement at hotels during those times.
Monthly Averages (San Jose)