OBJECTIVE Construction worker health and safety is a primary concern for construction companies and researchers. Arabian Gulf region, like Saudi Arabia, has been experiencing extremely hot and humid (EHH) weather, which directly affects construction workers' health and safety. This study aims to address the problem of EHH weather conditions and their impacts on construction workers' physiological status. METHODS This study assesses the impacts of EHH weather on construction workers' physiological status through the measurement of workers' physical body parameters (age, height, and weight); type of activities; and assigned tasks. Thirty-five multinational workers participated in the measurements, which were conducted in real construction site conditions A quantitative analysis was then applied to quantify the physiological impacts of the weather conditions. Several hypotheses were tested to identify the significant impacts of individual and working aspects on the workers' physiological responses. CONCLUSIONS The results provide empirical evidence that the recorded Heart Rate (HR) exceeded the acceptable physiological zones for construction workers exposed to extremely hot and humid weather conditions. Physical body parameters, work activities, and worker status significantly influence construction workers' physiological responses. This study recommends adopting a continuous monitoring approach as an early warning system under extremely hot and humid weather conditions.