Slow and hot

Im not sure why I am feeling so sluggish but I am pretty sure its the heat. These next 4 weeks are my base weeks and this week I have 11 miles scheduled plus cross training(road bike). Tuesday I ran 3 miles during lunch and the temp was 90 plus the humidity. This morning I ran 4.78 out of the 5 planned, I just misguided my run. Total min. for that was about 54 min. at an 11:12 pace.