Want to know which way the wind is blowing? Employ the scientific method and do a little observation. Here are three possible options to consider:
1. Go outside with a plastic bag. Hold the bag out and turn slowly in a circle until the bag begins to fill with air. Whatever direction you're facing, that's which way the wind is blowing.
2. Check out your neighbor's clothesline.
3. Stand in your yard and look up at the weather vane. Perhaps more accurate, but not nearly as fun.