Windy days can be annoying, but in regards to training they can be the best days for endurance training. If you’re on a longer ride and experiencing a lot of head winds you need to maintain a consistent smooth high cadence with no coasting or soft pedaling. Keep your elbows tucked body low and tap into your cardio system. You'll last longer and have stronger legs longer into your ride if you’re not mashing a big gear trying to fight it. There's always other days for big gear training. Mother nature can through some crazy things at you but use them to your benefit and learn. Focus and use this opportunity to be mentally tough and you'll come out stronger.