ABSTRACT
Precipitation in the forms of rain and snow is the major input to a watershed hydrologic system. Its occurrence, distribution, amount, intensity, and duration affect streamow, soil moisture, soil erosion, nutrient losses, and distribution of plant species. Precipitation in the forms of sleet, frost, dew, and hail, due to its lower occurrence and small quantity, is less important to hydrology. Hydrologic studies and watershed research are mainly concerned with rain and snow.
