The presentation will focus on significance of trust in scientific activities in general and forecasts in particular. The presentation will use Advanced Hydrologic Prediction Service (AHPS) as an example to elaborate following points: It is necessary and important for scientists to understand severe weather events like flooding better, however, it is not sufficient. Unless the public or users, sophisticated or casual, make sense of that understanding (by the scientists) and act on it, the improved forecasts will remain academic or pedantic. In a democratic society, science and society should not be two separate spheres because there is as much society inside science as outside. If science is practiced and legitimized in a society, then communicating the activities and results of science in less opaque language assumes importance. AHPS is such an attempt. With the introduction of probabilistic forecasting it became important to communicate clearly how the users can use this information in making risk-based decisions. It was important to translate what hydrologists wanted communicate with users so that forecasts and warnings were clear. It was equally important to communicate in transparent manner how the forecast was developed so that users understood the benefits and limitations of such forecasts. The presentation will provide an account of how National Weather Service is trying to develop trust in new forecast regime.