At an altitude of 18.40 Km the temperature is 147.54K and at 78.11 Km it is 567.00K, What is the temperature at 61.5 Km?
I have no idea what model you are using for the temperature of high altitudes.
Whatever it is, it is an odd one.
http://www.aerospaceweb.org/question/atmosphere/atmosphere/layers.gif