When it gets really windy, I often use a Pro-Tec helmet while windsurfing. It works great most of the time, but as the weather gets colder, the helmet has a number of little problems:
I am talking about the ventilation holes - they give me an ice cream headache when it gets cold. Wearing a hood underneath helps somewhat, but when the temperatures drop towards freezing, the ventilation holes are just a bad idea. And we are getting there now, especially when the wind comes from the north.
I could have simply spent $120 to buy another helmet, but since I have only one head and thus don't need two helmets, I decided to address the problem with a knife and a plastic pool noodle. Plastic pool noodles are an extremely valuable tool for windsurfers: cut of 10 cm pieces and put them in the foot straps so they don't get crushed when stacking boards; cut them in half and put them on the roof rack or trailer as a cheap cushion; or cut out little pieces to fill holes in the helmet during the colder seasons:
Here is the image of the final product:
I may also tape the holes close with some electrical tape, but I don't think its necessary. Now all I need is 35 mph winds to try it out :)