I struggle with tempo runs.

I can never figure how fast I'm supposed to go.

I don't know how long I should warm up before I start.

And I stink at maintaining an even pace.

So yesterday when I set out to do my first tempo run of this training cycle, I pretty much just winged it. I decided that tempo runs should be faster than my pace runs (should they?) and that I would shoot for maintaining 8:30ish per mile (I'm training to do my pace runs at 9:10, so is 8:30 reasonable?)

My schedule called for a 30 minute tempo run. I decided I'd do five minutes of that warming up, and then use five minutes at the end to cool it down and push hard for the 20 minutes in the middle. Is that the way you're supposed to handle these things?

Now I made all my decisions about the tempo run with no regard for the weather. I figured I could tough it out no matter what.

Wrong.

My splits ended up looking like this:

Mile 1: 8:56
Mile 2: 9:07
Mile 3: 8:32
.41: 4:42 (that was cool down time)

Not anywhere close at all.

But then look at this morning's splits. It was my easy day. My sole focus was to take it nice and easy and loosen up my legs.

Mile 1: 9:39
Mile 2: 9:40
Mile 3: 9:20

Those splits are much more evenly paced. There were some nice downhills in the last mile that sped things up. (Side note: It was already 77 degrees at 5 a.m. with 79% humidity and a dew point of 71. I pretty much wanted to die while running this morning)

I really need to figure this tempo run thing out. How hard to push, how fast to go and how to better keep my pace even.

Please share your running wisdom with me. Am I going about these runs all wrong? Where can I improve?