Tamarindo weather is always warm, and the sun shines just about 365 days per year! Only in rainy season will it rain lightly for an hour or two in the afternoon. Packing for Tamarindo is very easy, since it never gets cold and a pair of shorts, T-shirts, and in rainy season a thin long sleeved shirt, is enough.
The great thing about the weather in Tamarindo is that it is generally extremely predictable. November is the beginning of dry season and one of the best months to visit.
Although the rains have stopped everything is still very green. In late December the offshore Papagayo winds start to blow, and they will pick up in the months of January and February.The advantage of the offshore winds is that it keeps the temperature from getting very hot, it stays dry and is great for the surf. It will however make the ocean choppy and rough.
In mid March the winds start to die down and in April the Papagayos stop, making Tamarindo very hot and dry. Sometime during May everyone gets super exited because the first rains will arrive and within just a couple of days the dusty countryside will be covered with a carpet of green. Afternoon showers will continue until the end of rainy season with the exception of July which is Indian summer.
Towards the end of rainy season in September and October it can rain all day, although usually not more than 3 or 4 days in a row. Occasionally a hurricane forming in the Caribbean can cause rain storms in Costa Rica, called Temporal. A Temporal usually only happens late in the rainy season and can last up to a week and cause flooding throughout the country. Green season can bring some bugs, so make sure to bring repellent.