Wounded Warrior Half Marathon training: Week 3 complete

Last week's plans:
Sun: Rest
Mon: Short run 2 mi + pushups, crunches, lunges
Tues: Power yoga - I was hoping to make it to class at Lululemon but it was storming and I didn't feel like leaving the house. So I did Yoga Sculpt from ExerciseTV.
Wed: Short run w/ intervals easy 2.6 mi
Thurs: Short run easy Rest
Fri: Yoga Interval run 2.45 mi
Sat: 7 mile run

Saturday's run was tough. My legs were feeling great, but it was so hot and humid that the rest of me couldn't keep up. I stopped several times for walk breaks. I start my long runs between 8:00 and 8:30am and have debated getting up earlier to avoid the heat of the day. Since my half marathon starts at 8:00 I wonder if that would be a good idea since I would be running in the heat on race day.

Thoughts?

This week's plans:
Sun: Rest
Mon: Short run
Tues: Lululemon yoga
Wed: Short run
Thurs: Short run w/ intervals
Fri: Yoga
Sat: 8 mile run