Focus on Flash Floods

HURRICANES can be devastating. Large-scaleflooding can seem overwhelming. They certainly catch national attention. But weather news generally misses the most dangerous natural hazard of all: flash floods.According to the American Meteorological Society (AMS), such floods are the leading cause of weather-related deaths in the United States.This is a hazard that has to be dealt with primarily at the local level. And, at that level, it isn't getting the public attention it deserves.The AMS points out the danger: "Too many people live along small streams that can easily flood." A single storm can cause several disasters as it suddenly floods different small watersheds. This happens most often at night. Many victims are caught in cars and buses.Continuing efforts to improve the flood warning system have not licked this problem. Now the AMS looks forward to "revolutionary advances in flash-flood detection," thanks to new technologies. These include the advanced radars the National Weather Service is installing and improved satellite monitoring. Better ways of estimating rainfall from radar echoes also will help. To make the most of this new technology, weather scientists need a better knowledge of how water accumulates and flows through small catchment areas. They need to know how to connect what happens locally with the larger weather scene. The federal government should support more research in this field. However, none of this will reduce the flash-flood hazard without more local public awareness of the danger. The key to cutting flash-flood fatalities is better land-use planning and a public well-drilled in what to do when a flood warning comes. Like people living in tornado country, individuals living in flash-flood terrain need to be ready to act at any time. They need preplanned evacuation procedures and predesignated shelter areas. Local news media are doing a good job in getting general warnings out. But the AMS says their warnings would be even more useful if they identified individual streams and crossings that have become dangerous.Flash floods now may be North America's most lethal weather hazard. But communities can cut the death toll through more effective warning, disaster planning, and public response, just as they have with hurricanes.