It was 45 degrees when I left the house, I made it 3 miles from the house and turned around to take the car. Simply put, I didn't have the right gear. No tights or windproof pants, gloves were at home, but I only had ski gloves, so I was stuck. Hands were numb by the 3rd mile anyway, and my toes were not far behind... and I still had 15 miles left.