The graph bellow shows the relation between Pressure and Temperature for a single braking event

Peak rotor temperatures can be at least twice as high as what is calculated . 
Higher rates of deceleration will increase the peak rotor temperature more since the braking system has less time to dissipate the heat generated.
Under multiple decelerations, the temperatures move progressively higher because the rotors do not have a chance to cool to ambient temperatures.

(time=10 sec. ; Initial speed=50mph=80kmph) for a front brake rotor (weight=18lb=8.2kg)