Definitely the best period to visit Costa Rica and to surf is during the winter time, between December and April. These are the months where the wind reaches its highest average and the sun is guaranteed, specially on the north Pacific beaches. This is also the dry season. During the day it's hot but dry and the nights are cooler. All year around the temperature is between 22 and 34 degrees C°. The water is about 28°C, a shorty is used only some days of the year.
From each airports take the Panamerican highway to the North until the town of La Cruz and Sardinal. Then get to Hermosa. It's very easy to move around by car or by bus. Rent a four wheel drive could cost approx. $350 per week and the longest bus route is not more then $5.
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