The importance of base layers is often overlooked as most outdoor enthusiasts focus on their external jackets or pants. For example, a three-layer Gore-Tex jacket may keep any moisture out, but wearing the wrong base layer underneath may cause sweating, and then you’re wet anyways.I’ve been wearing a The North Face Hybrid Crew Neck for a few weeks now (has been washed a few times in between uses, but is odor resistant anyways) in a variety of conditions, and have been extremely pleased with how warm (neutral temp to warm) and dry I’ve been. The Hybrid Crew Neck is 75% hollow-core-polypropylene, having both thermal and breathable characteristics, is extremely lightweight, and has a seamless construction for added comfort. It is tight fighting, yet is still extremely comfortable. At $70, it’s a bit more expensive than that long sleeve t-shirt you’ve been wearing, but being dry and warm is well worth it in my book. For more info, check it out on the TNF website.