Speed workouts are back

I suppose it's time I started to actually train to meet my half marathon goal. I've been running regularly since the Austin half but just running. No speed work and no hills (unless they are part of the long run route).
The party is apparently coming to an end.
I did my first tempo run last Tuesday. 5 miles or 3 miles and then 2 miles depending on whether you believe in a water break during a tempo run. The 5 mile tempo went smashingly well. The 3 then 2 mile version, not so well. I did my last two miles slower than the first three. I'm chalking this up to the weather.
Here, I can even prove it mathematically:
Heat + Humidity = slower G
There! Now, it has to be true.

So yesterday, I did some fartleks on the indoor track. I forgot my watch at home so I did it by distance instead of time. 1.5 laps on (i.e. fast) .5 laps off (slow). Approximately 2.5 mins on, 1 min off. Once my body got past the shock of running in 75 degree weather, it adjusted pretty well.
I used to run on the indoor track after I tore my ACL but before I had surgery for it. While it can get monotonous; running on the treadmill really puts it in perspective. I would rather run on the track even though its only 1/7th of a mile long. Treadmills are too rickety for me. I sway too much on them.
Trick to running on an indoor track, it seems, is to have something else to do. Speed work may be the best suited to an indoor track when it's ridiculously hot or cold outside. So the plan is to do speed work once and week. I made the mistake of mentioning this to my trainer and she may have me do hills once a week too.
I really, really hate hill workouts. Like "why is the sky clouded over today but it's still 100 degrees outside" hate.