[MENTION=457988]Hoopdriver[/MENTION] is right. The apparent wind is different from the true wind, and there is almost always an apparent headwind on a bike. When I learned to sail, I learned to gauge wind direction with my ears and cheeks. Spin your head around until the noise in your ears or the feelings of your cheeks are equal. You have to do this when standing still. Or you could mount a chopstick to your handlebar vertically and hang a piece of soft twine from it.

[MENTION=71490]Wilbur Bud[/MENTION], that's a great web page. I bookmarked it in my weather folder.

Also, everyone should bookmark the US wind map or the World wind map and check it in the morning.