Given the potential for extreme weather conditions to cause significant damage to both property and human life, it is imperative to take action to mitigate the impact of such events. Buildings as one of the main shelters of peoples' lives become critical to study. Especially, building envelopes components that seal the buildings and act as a barrier between indoor and outdoor environments are imperative to evaluate their thermal performance. Moreover, the incorporation of prefabricated wall panels can play a pivotal role in addressing challenges associated with extreme weather conditions due to their capacity to enhance structural resilience, accelerate construction, and encourage sustainable practices. While prefabricated construction has been shown to offer significant advantages in energy conservation, low-carbon emission, and environmental protection, its thermal performance remains uncertain when subjected to significant temperature fluctuations. Therefore, the objective of this paper is to evaluate the dynamic thermal performance of a prefabricated wall panel under extreme weather conditions. Accordingly, a prefabricated wall panel was tested in an environmental chamber, simulating a heat wave that occurred in Chicago in July 2012. The metrics of Decrement factor (DF) and Time lag (TL) were used to measure the dynamic thermal properties. The results show DF of 0.07 and TL of 8 h indicating when considering thickness as a factor, the tested wall panel exhibits superior dynamic thermal performance compared to the other wall panels from the literature. This study provides valuable insights into the impact of building materials and design on energy efficiency and indoor thermal comfort.