When layering up intended for cold weather conditions its ideal to start with a close fitting thermal vest which will wick out moisture and also keep you heated by trapping air near to your body. Second is a lighter fitting top which will behave as a screen in between your waterproof and the warm internal lining of the vest. The 3rd layer would ideally be a water-resistant of some sort. This must protect not merely from above when rainwater will be piling straight down but additionally from beneath as mud and rain water is thrown up from the wheels and puddles while you race along on your bike.
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