IBMs Spatio-Temporal Epidemiological Modeler is a stand-alone open-source system that is used for modeling disease propagation based on user-set parameters. Its strength lies in its multi-model approach in designing a simulation, and through this implementation, STEM is able to create a scenario using various population, geographical, and disease models that interact with and affect each other. This paper discusses improvements on STEM by creating a cloud based version through web services. Specifically, this paper presents the design and development of web services leveraging on the functionality of STEM. The team is composed of developers and epidemiologists from the Department of Health (DOH), Philippines. In designing the web interface, the developers work closely with epidemiologists from the Epidemiology Bureau of the Philippinesâ€™ Department of Health, the target users. By doing so, they were able to identify functionalities that are needed and also those that were deemed unnecessary, which was ultimately not included in the web interface. Examples of identified needed parameters include the input fields for the number of initial infected people and for the specification of the start and end date of the simulation. Web services developed include: input, transmission, processing and visualization using open-source technologies, such as the Go Programming Language, MongoDB, and Leaflet.js. The Web interface is designed to act as a layer between the epidemiologists and STEM, with the local STEM used for creating the base models and scenarios, and the web interface used for forecasting.