WMO Hydrological Observing System

WMO Hydrological Observing System

The WMO Hydrological Observing System (WHOS) is  a portal to the online holdings of National Hydrological Services (NHS) around the world that publish their historical observation and/or real-time data without restrictions or cost. It represents the hydrological component of the WMO Integrated Global Observing System (WIGOS).
Important Notes: WHOS is being developed and implemented in phases.  The map interface appearing above is a provisional product designed for demonstration and testing in preparation for a review of the WHOS concept at the 15th Session of the Commission for Hydrology (CHy-15) in December 2016.  A full WHOS implementation is subject to approval by CHy-15. 

Hydrology & Water Resources Programme, © Simon Avinge

Hydrology and Water Resources Programme

Providing better hydrologic information, assessments and forecasts, so that Members are able to independently assess their water resources and respond to the threat of floods and droughts.

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