Economic systems are rife with heterogeneous risk events that have the potential to cause disruption. The diversity of risk types makes it challenging for companies to conduct comprehensive risk analysis for any chosen business opportunity. The current practice is laborious and expensive, involving internal risk analysts and external risk advisory services. In this paper, we present a cognitive system that augments human abilities, with the objective of drastic improvements in the productivity of risk analysis efforts. Our system is provided with a comprehensive risk taxonomy and its textual description along with an extensive corpus of textual data such as news articles. Using a series of textual analysis, knowledge extraction and machine learning techniques, the data corpus is annotated with risk-related information and indexed in a risk store for flexible query and retrieval. Our system interfaces with the risk analyst using a query orchestrator which translates analyst queries that are posed at a high level into lower level queries that are expanded to exploit the system's risk-related knowledge. It also enables formulating a graphical model and assessing the required probabilities; we introduce a particular family of models that can succinctly represent risk events modeled as stochastic processes over a long time horizon. We illustrate how a risk analyst can query the system to build a risk model with the help of a case study.