Effective warning for flash flooding is extremely difficult given the localized nature and rapid onset of intense rainfall and the fast hydrologic response of small basins. Flash floods can occur within minutes or a few hours of excessive rainfall. All the steps in the warning process need to be effective and completed in the least amount of time possible. These steps include: computing the rainfall, modeling the basin response, analyzing the situation, communicating the warning message, and completing life saving actions such as evacuations. This paper will describe some of the tools and techniques being used to improve each step in the National Weather Service's end-to-end flash flood warning process.

With the opportunities presented by both the Community Hydrologic Prediction System (CHPS) and the resources of an Integrated Water Resources Science and Services (IWRSS) program and the National Water Center facility, flash flood services delivery will most likely evolve significantly in the next 5 to 10 years. Some of the potential changes will be discussed.

Successful implementation of new flash flood warning technologies and best practices will lead to improved warning services and fewer lives lost to these destructive events.