Crack in concrete surfaces is one of the earliest signs of decomposition of the essential structure and constant exposure will cause serious damage to the structure and environment. In most of the safety assessment and fracture mechanic applications proposed that these cracks and defects eventually will grow and will have potential lead to in-service failure. Crack in concrete surfaces is one of the earliest signs of decomposition of the essential structure and constant exposure will cause serious damage to the structure and environment. Currently, non-destructive methods are getting popular in the field of inspecting defects in structure and one of them in trends is that using the thermographic image to detect hidden effects. However, the accuracy of the thermal camera, also called resolution, is highly dependent on camera variables such as lens, detector, sensitivity etc. Also, the most important question that needs to be answered for this research is what happens to the image in fog, rain or other climatic conditions where the camera detects crack which exceptionally smaller than most thermographic applications detects. This paper investigates the accuracy of thermal images obtained by the thermal camera under various weather condition and aims at providing information about optimum choice of environmental condition where the more favorable thermal images can be obtained and increase survey reliability and accuracy of the analysis.