NWM Retro- National Water Model retrospective forecasts

Multi-decade CONUS retrospective simulations from the NOAA National Water Model

The NWM retrospective¹ (sometimes incorrectly refereed to as a reanalysis²) takes the configurations of the NWM Version and reruns the model for a full series of landsurface flux data. From https://registry.opendata.aws/nwm-archive/:

One application of this dataset is to provide historical context to current near real-time streamflow, soil moisture and snowpack conditions. The retrospective data can be used to infer flow frequencies and perform temporal analyses with hourly streamflow output and 3-hourly land surface output. This dataset can also be used in the development of end user applications which require a long baseline of data for system training or verification purposes.

Some of the highlights:

• There is “no nudging”, so streamflow comparisons at gages need not worry about “contaminated” model outputs.
• See also: NWM oporational forecasts.

Footnotes

1. a rerunning of the model configuration to create a seamless historical record

2. a rerunning of a model with the express objective of improving the skill of the forecast