Quintero et al. (2026) Evaluation of Short-Range Streamflow Forecasts at Flash Flood–Prone Basins with the National Water Model

Identification

• Journal: Journal of Hydrometeorology
• Year: 2026
• Date: 2026-07-01
• Authors: Felipe Quintero, Witold F. Krajewski, Humberto Vergara
• DOI: 10.1175/jhm-d-26-0026.1

Research Groups

• IIHR Hydroscience and Engineering, The University of Iowa
• Office of Water Prediction

Short Summary

This study evaluates the performance of the National Water Model in predicting short-term streamflow across the United States, with a focus on small basins prone to flash flooding. The results show that forecasts often struggle to anticipate high flows more than a few hours in advance due to model initial conditions and errors in rainfall forecasts.

Objective

• Evaluate the probability of detection (POD) of high-flow events at small basins prone to flash flooding.
• Quantify the impact of modeling system components, streamflow data assimilation, and quantitative precipitation forecasts on forecast skill.

Study Configuration

• Spatial Scale: Continental United States (CONUS)
• Temporal Scale: Short-range forecasts (up to 7 hours)

Methodology and Data

• Models used: National Water Model (NWM) with High-Resolution Rapid Refresh (HRRR) model for precipitation forecasts.
• Data sources: Hourly observations from U.S. Geological Survey (USGS) locations.

Main Results

• The median POD of high-flow events reduces from 0.8 at the first hour to zero after 7 hours when streamflow data assimilation is used.
• Without streamflow data assimilation, the median POD reduces from 0.1 at the first hour to zero after 5 hours.
• Errors in precipitation forecasts reduce Kling-Gupta efficiency (KGE) at headwater basins.

Contributions

• This study highlights the limitations of current forecasting systems in predicting high-flow events at small basins.
• The results suggest that improving model initial conditions and rainfall forecasts are crucial for enhancing forecast skill.

Funding

• This research was supported by the Office of Water Prediction and the National Science Foundation.

Citation

@article{Quintero2026Evaluation,
  author = {Quintero, Felipe and Krajewski, Witold F. and Vergara, Humberto},
  title = {Evaluation of Short-Range Streamflow Forecasts at Flash Flood–Prone Basins with the National Water Model},
  journal = {Journal of Hydrometeorology},
  year = {2026},
  doi = {10.1175/jhm-d-26-0026.1},
  url = {https://doi.org/10.1175/jhm-d-26-0026.1}
}