1. A method for displaying a thermal image of a scene in an infrared (IR) thermal camera, the method comprising: registering a first air temperature value (T A ); registering a second air temperature value (T B ); calculating a threshold temperature level value (T Iso ) based on the registered T A , the registered T B , and a temperature color alarm level (T CAL ); imaging, by the IR thermal camera, a surface area to capture the thermal image, wherein the thermal image represents a temperature distribution in at least a part of the surface area; comparing a surface area temperature in at least one image point of the thermal image to the T ISO ; adjusting the color of the at least one image point in dependence of the relation between the surface area temperature in the at least one image point and the T 130 to create a colored version of the thermal image; and displaying the colored version of the thermal image.