Ventusky: Weather Forecast Maps

The application displays two types of waves: swells and wind waves. Waves travelling outside of their place of origin, and are thus not caused by local winds, are called swells. Waves caused by winds in that specific location are called wind waves. In the application, wind waves are marked in white and swells are marked in black. This feature allows you to quickly find areas where high wind waves are travelling in a different direction from the swells. Significant wave height is the average height (trough to crest) of the one-third highest waves. Given the variability of wave height, the largest individual waves are likely to be somewhat less than twice the reported significant wave height for a particular day. Wave period is time interval between arrival of consecutive crests at a stationary point.