Going out too fast

What a day. Thankfully, the remnants of the tropical storm weren't too bad out by me and I was able to get in my hard SOS run today. I haven't yet figured out what my pace is when I first set to running; I almost always go out far too fast compared to the desired pace. Today was more of the same. 

While I may have naturally pulled back a little bit, and then pulled back a little bit more once I saw what my pace was, that doesn't lessen the fatigue that I went through needlessly in those first 15-30 seconds. My pace was supposed to be 6:05/mi for my ½-mile intervals, but I kicked off my first one at 5:11 pace. Granted, that didn't last long at all, but it's still way too much of a burst of energy. It took me about four intervals to come much closer to the right pace from the outset of the interval in question. Anyone have a good idea for how to properly get to the right pace quickly, without overexerting oneself? Treadmills make it easy, but those aren't helpful when training outdoors. :-)

Mile   Planned    Actual   

.5       3:03          3:05

1        3:03          3:02

1.5     3:03          3:00

2        3:03          3:04

2.5     3:03          3:03   

3        3:03          3:15

3.5     3:03          3:06

4        3:03          3:14

5        6:30          6:49

The other interesting thing to note about today's run is that my initial (and every other) segment was slightly downhill (about 30 feet), with the intermediate/return segments being back uphill. Despite the moderate headwind on the downhill segments, those segments (save for the first one) were always faster than the return trips. That such a mild hill has that much of an effect is rather notable. Definitely explains why there is as much of an effect as there is on my runs during the obvious uphill segments.