Drought forecasting systems use models fed by climatic and atmospheric data (historical/seasonal weather patterns, real-time meteorological monitoring, and weather forecasts) to predict the probability of a drought occurring in a region or area of interest in the future (up to approximately three months).
if you interest to do flood modelling contact NCCR (National Centre for Coastal Research). they did modelling for Chennai and Mumbai for future flood that means based on rainfall where the places getting more inundation, at what time it reach along the area will useful to evacuate the people and safe the property.