For years, I used Windy.com to visualize wind patterns at various levels of the atmosphere for my high altitude balloon and rocketry launches. I also use it at sea level while sailing. It is the best app for both use cases.

I recently learned Windy now visualizes almost any weather parameter you can think of – see the right side of the screen. Of particular interest to San Diego sailors and surfers is wave direction, shown above. Kayakers – notice it also shows wind-caused waves on the larger inland bodies of water.