After doing all the excellent suggestions above, you find you still have the occasional capsize to windward, you can often save it by not coming into the boat.
If you hike out horizontally into the water, and stay in the hiking position, you will unweight the boat because your body will be in the water, supported by the water. So the boat won't capsize on top of you. If the lull is brief, you will be picked back up when the wind resumes. Sounds strange, but really works to stop a capsize. Yea, I know it is cold.