6 mi at GMP.
I used Power to guide my effort today, and my plan was to shoot for 270-275 Watts. BUT, it was so incredibly HUMID and Hot. 2 days ago when I did the Intervals workout, it was 50 F, cool and dry. Today was 75 F and humid, and it felt like I was in a sauna from the start. After a 2 mi w/u, I very quickly realized that I wasn't going to be able to run at 270-275 W steady for 6 miles. I ran at what felt like a comfortable effort, which appeared to be in the 260-265 W range, so that is what I aimed for. Toward the end, I pushed it up closer to 270 W, but it was not comfortable at all.
I am not concerned; this is probably about as good as it gets on a day like this, and the training effect of the heat/humidity is probably quite strong, so I'll take it.