Radar applications for measurement of areal precipitation are reviewed. Radars with a beam width of 2° or less and a wavelength of 10 cm should provide improved measurements of areal rainfall and more timely and comprehensive rainfall reports. However, substantial realization of radar's potential in operational hydrology requires further examination of the correspondence between radar and rain gage data, refinement of communicating and computer‐processing techniques for radar data, and development of means for measuring precipitation echoes in the presence of terrain echoes. (Key words: Rainfall; instruments, radar)