[TXnMA]

Contrail formation, lifetime, and spread are not solely a function of elevation. If it were, the A/C who consistently fly the major west-east corridor I live under would always make persistent contrails. [ve seen days where planes flying straight and level have contrails that "switch on and off" as they traverse streaks of air with different properties.

You probably could get better info from the gentleman at contrailscience.com if you address him nicely -- but I guess that is a (your word) suggestion...:-}

[TigersEye]

The weather system that existed there at that time extended to the east slope of the Rockies and was quite humid. The contrail should have persisted all the way to Phoenix for awe808 and certainly as far as LA for UPS902.