Digressing from ATIS
When starting a Non FADEC hot engine the engine should be run to MAX motoring speed to cool the engine prior to selecting fuel, this could be as low as approx 100 deg C so high ambient temp will not really effect the starting cycle.
A FADEC engine would automatically do this for you.
For example I have timed a Trent 700 motoring for 40 seconds to reduce the internal temperature before fuel light off.