Here are some links around sea areas, weather and other useful stuff.
Navionics online nautical chart (Navionics nautical chart available online)
Maritime weather croatia (Current maritime weather report of the DHMZ Croatia)
Grip weather data (Global weather data from GRIP data)
Buoy fields croatia (great overview of the croatian buoy fields)
Ferry croatia (official site of the croatian ferry company Jadrolinija)
Tide calculation worldwide (UK Hydrographic Office website - select port and view tide)
If you think more links would be useful, please feel free to send me a message.