Expert Report

Each report is produced by a committee of experts selected by the Academy to address a particular statement of task and is subject to a rigorous, independent peer review; while the reports represent views of the committee, they also are endorsed by the Academy. Learn more on our expert consensus reports.

The nation's network of more than 130 Next Generation Radars (NEXRADs) is used to detect wind and precipitation to help National Weather Service forecasters monitor and predict flash floods and other storms. This report assesses the performance of the Sulphur Mountain NEXRAD in Southern California, which has been scrutinized for its ability to detect precipitation in the atmosphere below 6000 feet. The report finds that the Sulphur Mountain NEXRAD provides crucial coverage of the lower atmosphere and is appropriately situated to assist the Los Angeles-Oxnard National Weather Service Forecast Office in successfully forecasting and warning of flash floods. The report concludes that, in general, NEXRAD technology is effective in mountainous terrain but can be improved.

Key Messages

  • The committee finds that the Sulphur Mountain radar is appropriately sited to detect approaching storms while avoiding problems with anomalous propagation of the radar signals.
  • The radar is amply functional and has provided crucial support to the Los Angeles-Oxnard forecasters in their mission to monitor, predict, and warn of precipitating events and flash floods.