I've been wearing wool for more than 30 years, and have watched it fall out of fashion, and lately, become quite trendy. Different weights give you different amounts of warmth, and the weave determines how well it vents when you get too warm and sweaty. Wool has 2 great properties: it keeps you warm even when damp (more warm than synthetics, anyway), and it resists smells. I've got different base layers and jerseys for different temperatures. For this jersey, there's not enough information to tell the exact temperature range, but if it's like other long-sleeve wool jerseys, it would probably work in the 40s with a base layer and a top wind layer, the 50s with either a base layer or a wind layer, and the 60s and low 70s on its own. The other important information that's left out of the description is whether its made of merino wool. Merino isn't itchy or scratchy.