A.M. Workouts

I flip around between working out in the mornings during the winter and the evenings during the summer, and I never really notice a difference in power output/RPE for the two. It is a bit harder to get warmed up in the morning, becuase my body is still pretty stiff when I hop on the bike. If I want to do a workout with any sort of intensity in it I have to do a good warmup that includes a few 5-10 minutes of easy L1 and L2 riding, and then a few 1-2 minute "blow out" efforts in upper L3 and L4. Once I've done that, though, I can do any workout with the same wattages that I would see in the afternoon.

One thing that I do a little differently from you, though, is that I get up 30-60 mins before I ride and eat a light breakfast and have a cup of coffee. I would definitely feel like **** on the bike if I hopped on 15 minutes after rolling out of bed. So you might try getting up a little earlier, have a bit of solid food before you get on the bike, and see if that helps things.