Ponded water depth
Modeled depth of water ponded on the land surface for a geographic grid cell and valid time; configuration, initialization, code version, and model release must accompany it.
Sources that carry it
2 sourcesOperational NWM analysis and forecast output family published as NetCDF files. Terrain-routing grids directly emit modelled ponded-water depth (sfcheadsubrt) in millimetres at 250 m for CONUS and southern Alaska and 100 m for Hawaii and Puerto Rico/USVI, with model initialization time, output valid time, model configuration, NWM version, and code version. It is model output, not a satellite observation and not the separate NOAA Flood Inundation Mapping service.
Open multi-decade historical NWM simulation archive, versioned by NWM release and distributed in NetCDF and Zarr/cloud files. RTOUT terrain-routing files directly emit modelled ponded-water depth every three hours. Retrospective runs use observed rainfall and meteorological reanalysis but do not assimilate stream-gauge observations; they are model reconstructions, not direct flood observations.
Questions it helps answer
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