Thursday long run

It's been a long time since I've done one of these so I will try to remember how...
It was cold this morning, like 33 degrees, so I decided to sleep in and run at lunch. Lunch time came around and no sun, no warmup. It was about 40 degrees overcast, and no sun. the plan was 9 miles on flatter course with 4 mile tempo in the middle at better than 9:30 pace.
Started off nice and easy, didn't feel too bad but it was mostly down hill for the first 2 miles. Then I hit the greenway and picked up the pace to 9:10, the first part was false flat down so I knew I should keep the pace up since when I made the turn around to come back it would be false flat up. I did the first two miles at 9:10 pace then turned around and started back, amazingly at mile 3 I was still on 9:10 pace, but I was starting to suffer, I started counting down the mile markers and concentrating on the heavy metal playing in my ears. 3.5 miles still at 9:10, but I knew I could not hold it for another half mile, so I eased up for the next quarter and my ave pace dropped to 9:13, now I was at the final quarter mile and I knew I could make it so I picked the pace up and dropped my ave pace back down to 9:12. When the four miles was over I had to walk for a quarter to recover. Finally I started jogging and went back up the hill to work and did an extra bit around campus to get in a little more for a cool down since running up that hill didn't really count as a cool down. finished with 8.7 miles in 1 hour 27 minutes.