near of lisbon you have 2 ou 3 very good beachs
you have Guincho with a lot of wind, it´s good for kite from 6m to 12m usualy i use my 8m.
you have beach of Rainha (praia da Rainha) beach of nova Vaga ( praia da nova vaga) and fonte da telha. all these beachs are near one from others. you choose what you like more.
and you have Lagoa de Albufeira, it´s a lake near by of the sea. you chose if you prefer ride in the lake our in the sea.
all beachs you can see the wind in
www.windguru.cz the second choice you can see in fonte da telha our costa da caparica. the distance from that 2 beachs are about 5km and the other beachs are in the middle. the best wind to ride in guincho and from the costa da caparica to fonte da telha its, NNW , NW, N, W, SW usualy yhe W and SW it´s rainy days in guincho the wind its usaly only NW and N.
in lagoa de albufeira the realy good wind its W our you can ride also with NW and NNW, with the rest of directions the wind and direction its very instable.
i hope this can help you..