In many parts of the country, flash flood watches and/or flash flood warnings are often issued during torrential downpours, especially in hurricane-prone and/or low-lying areas. Flash floods can be damaging and even deadly, so when an alert is issued in your region, it’s very important to remain alert and take action to ensure the safety of you and your family. But do you know what these alerts mean, how to prepare and what you should do? We’ve compiled some valuable information about what flash floods are, how to prepare and what to do when they occur.
As its name implies, a flash flood signifies rapid flooding that occurs in a short amount time – anywhere from a few minutes to about six hours. It is most often caused by heavy or steady rain brought by thunderstorms, tropical storms or hurricanes, and can also result from dam failures or rapidly melting snow or ice. Flash flooding may also occur when repeated rainstorms affect already saturated soil or dry soil unable to absorb a large volume of water. In all of these cases, flowing precipitation is channeled through streams or combines with other volumes of water, producing a quickly-moving and potentially destructive torrent of water and collected debris. What makes flash flooding especially dangerous is that it can occur when there is no rainfall in a local area at all – in that case, there is heavy precipitation affecting an area upstream.
When flash floods may or do occur, the National Weather Service issues two types of alerts: Flash flood watches and flash flood warnings.
Flash flood watch: Flash flood watches are issued when conditions are likely to favor the formation of flash floods.
Flash flood warnings: Flash flood warnings issued to notify you that a flash flood is happening right now, or will occur imminently.
Flash floods can be dangerous, damaging or even life-threatening, but by learning as much as you can and taking time to prepare, you can help protect yourself and your family if these natural disasters impact your local area. For more information on flash flood safety, contact the Red Cross and the National Hurricane Center if you reside in the United States. Or if you’re in Canada, you can contact the Canadian Red Cross and the Canadian Hurricane Centre for more information.