This book represents a sense of the weather community as guided by the discussions of a Board on Atmospheric Sciences and Climate community workshop. The book puts forth the committee's judgment and corresponding recommendations on the most pressing high level, weather-focused research challenges and research to operations needs. The book addresses issues including observations, global non-hydrostatic coupled modeling, data assimilation, probabilistic forecasting, and quantitative precipitation and hydrologic forecasting. The book also identifies three important, emerging issues--predictions of very high impact weather, urban meteorology, and renewable energy development--not recognized or emphasized in previous studies.