Hi, I live 20 km far from Tarifa. You can have all information you need from internet. Look here for example:
When wind is from W you normally use 12 meters or bigger
And when wind came from E (Levante) 12 meters or less
The water isnÃ‚Â´t very cold, you wonÃ‚Â´t be cold with normal neopren suit.
This is another very good web for chek the meteorology at Tarifa spot:
Good luck! and see you at the beach!
Ah! And if you also want night parties, come in summer, youÃ‚Â´ll be surprise, sure