Frequency distribution of annual peak water-equivalent on Wyoming snow courses

An empirical sample frequency distribution of annual peak water equivalent, W, expressed relative to the station mean, W(bar), was determined for all Wyoming snow courses having 30 or more years of records. Because tests supported the hypothesis of homogeneous variance amoung location and elevation cases, a composite distribution was derived that provides a reasonable approximation for all snow courses in the State. The modular co-efficient, W/W(bar), is approximately normally distributed, with mean 1.0 and variance 0.088. A table of exceedance probabilities is provided to facilitate application.