Epidemiological forecasting is critically needed for decision making by national and local governments, public health officials, healthcare institutions and the general public. The Delphi group at Carnegie Mellon University was founded in 2012 to advance the theory and technological capability of epidemiological forecasting, and to promote its role in decision making, both public and private. Our long term vision is to make epidemiological forecasting as useful and universally accepted as weather forecasting is today. I will describe some of the methods we developed over the past eight year for forecasting flu, dengue and other epidemics, and the challenges we faced in adapting these method to the COVID pandemic in the past few months.