Castelli Climber'S 2.0 Jersey Mujer, rojo/naranja

Castelli made this jersey specifically for hot weather, with a meshy fabric on the front that allows a lot of air to flow through the fabric to cool you, while on the back they created a fabric that blocks over 90% of UV rays while also being airy and lightweight. But don't think of it as a niche jersey that you only bring out for hot days. Add a base layer underneath it and you'll use it from mid spring to early fall, and the stretch of the fabrics that make it fit so great mean that it's extremely comfortable.