weatern Algarve in February
I've just spent a week at Carol's in the Western Algarve and went swimming in the sea 4 out of the 6 full days. The water was lovely, theory says that the sea is the same temperature there in February as it is in Bournemouth in June. However it felt warmer, there was no sudden hesitation moment at depth of 2ft 6in (varies by individual). I stayed in for ages without feeling cold and then came out and dried off in the sun. Such a super experience in Europe in winter.
I was at Praia do Zavial which is about a 40 minute walk from Carol's (quicker by car!). This beach gets cut off at high water - which means you don't get people wandering in on you (except that there is a coastal path just above the beach but that was no problem).
The surf was quite strong on all days and you had to watch the undertow and be aware of the potential for a rip tide, but the waves and the tow made it all the more fun. There were surfers at the other end of the beach, all dressed up in their wet and dry suits - if only they knew how wonderful it was to be natural...
I can thoroughly recommend Carol's as a place to stay, they looked after me really well during the week and their place has some lovely sun traps.