The data are being made available on a best effort basis by all parties involved. There are no guarantees the data will be available when you really need it.
National Water Model Retrospective Version 1.2
- 25 Year retrospective simulation (Jan 1 1993 - Dec 31 2017)
- A reanalysis rather than a reforecast (forcing different than real-time runs)
- Output fields are fewer and less frequent than real-time to conserve space
- Provides historical context to current conditions
- Can be used to infer flow frequencies and perform temporal analyses
- 584,384 objects, 21.7 Tb in size, with hourly streamflow output and 3-hourly land surface output
Reanalysis Technical Details
- Forced with NLDAS and NARR
- 1992 used as a warmup period so the data in 1993 is good.
- 1-km raster, 250-m raster, and vector data.
- Uses the NHDPlus flow lines, lakes, and reservoirs.
The data is being made available in a NetCDF file format. The data are a combination of raster in a projected format and vector data that must be referenced with associated geographical information located in other files.
Products Available & Name Conventions
There are several files which contain various output products for each time step. They are detailed below.
|Product Name||File Description||Time Between Files||Example File Name|
|CHRT||Streamflow and other values at points associated with stream channel flow lines||1-hour||201409090000.CHRTOUT_DOMAIN1.comp|
|LAKE||Output values at points associated with lakes & reservoirs||1-hour||201409090000.LAKEOUT_DOMAIN1.comp|
|LDAS||Land surface model output including soil moisture, radiation, ET, snow, etc. at 1-km resolution||3-hourly||201409090000.LDASOUT_DOMAIN1.comp|
|RT||Ponded water depth and depth to soil saturation at 250-m resolution||3-hourly||201409090000.RTOUT_DOMAIN1.comp|
The filenames are
Archive Data Access
Data access is provided via a S3-API compatible service. The files may be downloaded with the aws cli, boto, or through a web browser.
This endpoint is S3-api compatible, so when you visit in your browser it will return XML with a truncated list of files available to download.
aws s3 ls s3://nwm-archive/ --no-sign-request --endpoint-url https://griffin-objstore.opensciencedatacloud.org --no-verify-ssl
Real-time Data Access
If you could like to access a real-time data feed of forecasts from the National Water Model that data is available from NOAA at the following location.