Moderate heat (6)
(Other definitions for temper that I've seen before include "Tendency to anger" , "Toughen with anger" , "Volatile anger - don't lose it" , "Display of anger" , "Frame of mind" .)
(Other definitions for warmth that I've seen before include "Pleasant heat" , "Affection, kindness; emotional intensity" , "Mild heat" , "Ardour" , "Compassion" .)