THE DEFINITIVE GUIDE TO HITZ DISPOS

If regular air is generally made up of N2, O2, H2O and lesser quantities of other gases, then how occur the plasma glow we see in the course of a static discharge or lightning is blue? Due to the fact that listing appears to condition that a mixture of O2 and N2 would give you a orange-ish coloration. Or am I Erroneous in regards to the regularity?