My wakeup HR was 47. I had to leave home soon after I was up, so I didn't run until evening. I left home about 7 pm during a slight sprinkle of a rain. However, by the time I had gone 1/4 mile, it was raining pretty good (at least by desert standards :) I didn't check my thermometer before I left, but I would guess the temperature was in the 50s. All I was wearing was a thick long sleeved T-shirt, my running shorts, and my running hat, and I was worried about losing body heat due to wet clothes. However the heavy rain only lasted for about 15 minutes, and the T-shirt was thick enough that the rain didn't soak in until after my body was at running temperature. By the time I reached my turn around point, the rain was down to a light sprinkle, and by the time I reached home, the rain had stopped. I felt fine during the run and didn't feel cold at all. A nice run!