I'll back up Jason: the black pants are going to be marginally cooler due to the air flow. The "black is hotter" nonsense needs to end. Black absorbs more LIGHT, not necessarily more HEAT. Material and other factors are more important in temp feel.
In fact, I wear a bandana product called a Buff. They've got a UV (protection) black one that I will probably wear at some scrimmages under my hat. I want to weat it down to keep cool. I wear other dark colors on my morning run and they work great.