While windbreakers are primarily designed to resist wind and offer some level of water resistance, they may not be fully waterproof. Many windbreakers have a durable water-repellent (DWR) coating that helps shed light rain or drizzle. However, in heavy rain or prolonged exposure to moisture, windbreakers may eventually become saturated. For complete waterproof protection, it's advisable to consider specialized rain jackets or outerwear.