Type Remarks Precipitation Measured at least daily, indicates the gross amount of water applied to the land surface. Cumulative winter precipitation may be used as an alternative to snowpack if wintermelt and sublimation losses are considered.
Rainfall often contributes greatly to flooding.
Hydrometric Data Data on river levels and flows and lake levels. By monitoring upstream water levels and flows, the forecasters obtain an early indication of the timing and amount of the spring runoff. This facilitates forecasting for downstream areas. Soil Moisture Data indicating the moisture content of the soil and, conversely, how much may be absorbed by the soil. The amount of water not absorbed runs off the land into streams.