Climate change is affecting more and more local communities, which are now facing different hazards; in answer to this threat, specific actions at the local level should be taken. The Covenant of Mayors (CoM) is an initiative that tries to involve municipalities and communities in developing SECAPs, i.e., plans for sustainable energy and climate with the aim to develop adaptation and mitigation measures. In order to identify and evaluate hazards, the CoM developed a template relative to the current risk level and expected changes in the future. This paper develops a methodology to fill the template using a data driven approach instead of a heuristic one. The methodology was applied to the city of Trieste in northeast Italy and uses local weather station data and projections obtained from GCM-RCM models. Data were manipulated using different approaches for current risk levels and the Mann–Kendall test is proposed as a method to identify the future evolution of hazard intensity and frequency. The results showed that the developed approach could help municipalities in developing their SECAPs and in identifying the present and future evolution of hazards.