The Australian Bureau of Meteorology has a requirement for complex and evolving systems to manage its weather forecasting, monitoring and alerts. This paper describes an agent-based system that monitors in real time the current terminal area forecasts (forecasts for areas around airports) and alerts forecasters to inconsistencies between these and observations obtained from automatic weather station data. Categories and Subject Descriptors H.4 [Information Systems Applications]: Miscellaneous; D.3.2 [Language Classifications]: Java General Terms Design, Algorithms, Reliability Keywords Agents, Meteorology, Alerts, BDI, XML