The surface instrument network of the Upper Colorado River pilot project

The upper Colorado River Pilot Project is sponsored by the U.S. Dept. of Interior, Bureau of Reclamation. Its purpose is to augment precipitation in a 3300 square mile area in the San Juan Mountains of southwestern Colorado through modification of wintertime cold orographic clouds. The first project phase, initiated in November, 1968, provided for installation and operation of a network of surface instruments to collect meteorological data. A network of precipitation, wind, and temperature sensors was designed to provide an understanding of the physical processes and sequence of storm events which occur in this area and to permit evaluation of precipitation augmentation operations. The paper discusses the instrument network design, procedures developed for areal distribution of precipitation, and presents examples of precipitation patterns observed.