What type of windbreaker? I have one for summer use, but it is not proof enough for winter. Another one I have is made of heavier grade polycotton and is good for below freezing.
I figured out a "huff test" for windproofs. Seal the material against your mouth and give a powerful huff. Ideally some air should be forced slowly through under pressure. If the air goes through quickly, it's for summer. If, like a goretex, nothing budges, then its for rain.