National Drought Atlas: Expected Streamflow


Click on a USGS Region (1 to 18) to download an Excel file that will estimate the amount of streamflow that can be expected at selected stations in that state for non-exceedance intervals of from 2% (very dry) to 98% (very wet), and for durations of 1, 2, 3, 6, and 12 months.  The files are fairly large, but once downloaded, they can be saved and used indefinitely on your computer without further Internet transmissions.  The files also contain hyperlinks to other sources of data associated with each station's watershed.

The stations selected are a subset of USGS's Hydroclimatic Data Network (HCN).  The HCN stations measure essentially unregulated flow, and have long records with relatively few data gaps.  HCN stations which showed trends in the flow quantities over time were not included in the Atlas dataset.