Levy Trail/Ghetto Cat Loop

I alternated two-minute jogs with three-minute walks to complete two miles through thick fog on the Levy Trail this morning in 28:00 and noticed something that seemed unusual. I looked up when it was still dark and could see black sky and stars, even though the fog was thick enough to encourage me to run on the trail for the sake of safety. Is that the way it usually works?
All right, finally, my windows are open and the fan's on. It's 72°F at 5:33 p.m. I walked the Ghetto Cat Loop this afternoon in 30:58.