Measuring risk in the context of natural disasters is a key challenge in Humanitarian Logistics. Risk is generally understood as a function of hazard, exposure, and vulnerability. However, vulnerability is particularly difficult to quantify, especially when it involves human factors. In this paper, we perform and initial assessment of both exposure and vulnerability using various elements, including seismic zonification, building regulations, and population mobility. We use the earthquake that struck Mexico City on 19 September 2017, as a case study to develop our approach. Our goal is to contribute to the creation of an Urban Vulnerability Index to help decision makers reduce risk in Mexico City.