Flash Flood Forecasting Over Complex Terrain

Flash Flood Forecasting Over Complex Terrain

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 book 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 book 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 book concludes that, in general, NEXRAD technology is effective in mountainous terrain but can be improved.

Flash Floods

Flash floods typically develop in a period a few hours or less and can arise from heavy rainfall and other causes, such as dam or flood defence breaches, and ice jam breaks. The rapid development, often associated with a high debris content, can present a considerable risk to people and property. This book describes recent developments in techniques for monitoring and forecasting the development of flash floods, and providing flood warnings. Topics which are discussed include rainfall and river monitoring, nowcasting, Numerical Weather Prediction, rainfall-runoff modelling, and approaches to the dissemination of flood warnings and provision of an emergency response. The book is potentially useful on civil engineering, water resources, meteorology and hydrology courses (and for post graduate studies) but is primarily intended as a review of the topic for a wider audience.

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