This application calculates the direction of Evripos stream. You can find when the flow change and what direction has it every time.Also application gives a matrix of the waters flow direction for the whole moon month The Evripos or Euripus Strait is a narrow channel of water separating the Greek island of Evia in the Aegean Sea from Viotia in mainland Greece. The strait is located in Chalcis on Evia (or Euboea).The strait is subject to strong tidal currents which reverse direction approximately four times a day. Tidal flows are very weak in the Eastern Mediterranean, but the strait is a remarkable exception. Water flow peaks at about 12 km/hour, either northwards or southwards, and lesser vessels are often incapable of sailing against it. When nearing flow reversal, sailing is even more precarious because of vortex formation.(From Wilipedia)For more information about this phenomenon please visit www.antonios-antoniou.gr.