on this link, the institudo estadual do ambiente - inea, provides the suitability of several beaches, including praia do recreio - on this link an early morning shot of recreio beach is posted daily, showing water conditions.

published by surfline, this page displays the forecast for recreio beach at avenida glaucio gil - also by surfline, this clickable map shows the height of the waves on a number of beaches in both rio de janeiro and niterói - and this chart shows the forecast for all waves in rio's southern region.

published and updated daily by the brazilian navy, this page shows the overall daily forecast for rio de janeiro state's coast, including waves (ondas), visibility (visibilidade), and  temperatures (temperatura).