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Water Supply

Water Supply Outlook Report

The Water Supply Outlook Report (WSOR) contains water supply forecasts, which are statistical predictions of streamflow volume that will flow past a point on a stream during a specified period of time, typically in spring and summer. These forecasts are given not as a single number, but as a range of numbers to reflect forecast probability and uncertainty. Learn more about these forecasts and how to interpret them.

Click Here to Access Historical WSORs

This directory provides access to all historical reports from 1990 to present. To view a historical report, simply select the "Water Supply Outlook Reports" drop-down menu, then select the water year of interest.


Receive the WSOR and other related Snow Survey updates by subscribing to our e-mail list here.

Additional Resources

External Resources

Northwest River Forecast Center                                Oregon Department of Water Resources                     California Nevada River Forecast Center
   - 10-Day Streamflow Forecasts                                   Bi-weekly Water Conditions Report                       - Ensemble Forecasts
   - 120-Day Streamflow Forecasts 


Contact Oregon Snow Survey

Do you have questions regarding water supply or snow survey data? Please click the above header to send us an e-mail.