I ride on the hills of Medellin, Colombia (6500 to 9200 feet over sea level) and during my rides I encounter temperatures ranging from the low 40s in the early morning to the 80s or more in the afternoon. So for afternoon rides the jacket is pretty hot but since I ride mostly in the morning or at night it is perfect. I use it with a Castelli Mesh Seamless base layer. By the middle of the morning I take off the sleeves (since I have short arms it is sometimes a little cumbersome) and if the ride takes me into the early afternoon I can always open it and finish mi ride. Versatile enough for most of my high altitude rides.