NWM — NOAA National Water Model

Hourly hydrologic forecast at every NHDPlus stream reach (~2.7M reaches) in CONUS. Analysis-Assimilation runs hourly with 3-hour and short-range (18h), medium-range (10d), and long-range (30d ensemble) configurations. The natural input for parametric flood triggers and flash-flood validation.

ProviderNOAA Office of Water Prediction
Delivery modestream
CNR score80
CadencePT1H
Originhttps://water.noaa.gov/about/nwm