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7 Day HydroEstimator View of Precipitation over CONUS<br>Showing the Aftermath of Hurricane Irma - 13 September 2017

7 Day HydroEstimator View of Precipitation over CONUS
Showing the Aftermath of Hurricane Irma - 13 September 2017

Hydro-Estimator (HE)

Algorithm Description

The Hydro-Estimator (H-E) uses infrared (IR) data from geostationary satellites to estimate rainfall rates every 15 minutes over most of the globe with a product latency of less than 30 minutes. Estimates of rainfall from satellites can provide critical rainfall information in regions where data from gauges or radar are unavailable or unreliable, such as over oceans or sparsely populated regions, and the rapid refresh of the H-E makes it well suited for diagnosing the evolution of intense rainfall that can lead to flash flooding.

Satellite-based estimates of rainfall have been used operationally at NOAA / NESDIS since the late 1970's, starting with the largely manual Interactive Flash Flood Analyzer (IFFA; Scofield 1987), and then progressing to the fully automated Auto-Estimator (Vicente et al. 1998). The Hydro-Estimator (H-E; Scofield and Kuligowski 2003) is the current- generation operational algorithm at NESDIS and has been used since 2002.

Users and Applications

The Hydro-Estimator has been used operationally since 2002 in National Weather Service (NWS) Forecast Offices (FOs), mainly those with areas of responsibility outside the radar coverage umbrella. For instance, West Gulf River Forecast Center (WGRFC) uses satellite data in their multisensor precipitation analysis that forms the basis for their streamflow forecasts since much of the Rio Grande Basin is in Mexico and thus not covered by US radars. In addition, the nonprofit Hydrologic Research Center (HRC) has been using Hydro-Estimator rainfall as input to Flash Flood Guidance (FFG) systems that they have installed at a number of forecast centers around the world. The FFG system compares satellite-based rainfall estimates to estimates from a hydrologic model of how much rain is needed to induce flash flooding. These FFG systems serve countries representing over 10% of the entire global population.

Algorithm PI

Operational Product Access

CLASS Archive

  • Not yet available

Monitoring and Algorithm Support

Other HydroEstimator-related links

List of satellite/instruments for algorithm

  • GOES-13 and -15 Imager (GOES-13 to be replaced by GOES-16 Advanced Baseline Imager in November 2017)
  • METEOSAT-8 and -10 SEVIRI
  • Himawari-8 AHI