Water vapor is one of the most important variables in the atmosphere affecting weather and climate.
A better understanding of the temporal and spatial distribution of moisture throughout the troposphere will improve our ability to predict clouds and precipitation and to parameterize global climate processes. Furthermore, empirical observations of atmospheric water vapor are the only means by which we may confirm and refine our understanding of many important physical processes within the atmosphere. Modeling results have also shown that high resolution measurements of PWV used together with vertical profiles of winds from radar wind profilers can improve the short-term cloud and precipitation forecasts. This year the network was expanded from 9 to 15 sites, with new sites at Granada, Colorado, DeQueen, Arkansas, Palestine, Texas, Jayton, Texas, Winfield, Louisiana, Neodesha, Kansas. Three additional sites are to be completed by late summer of 1997 in Alaska.