National Weather Service United States Department of Commerce

The National Weather Service (NWS) has declared March 16 through March 22 as Flood Safety Awareness Week. The National Weather Service in {city} will feature information about a different flood topic each day during the awareness week.

 

For information throughout the week, like us on Facebook Follow us on Facebook and follow us on Twitter Follow us on Twitter.

 

Today's Topic: Floods Hazards


A flood is defined as any high flow, overflow, or inundation of water that causes or threatens damage.  Flooding can occur with prolonged rainfall over several days, intense rainfall over a short period of time, or when water from an existing source moves too quickly (i.e. snowmelt, dam break, etc.). Brief descriptions of the various types of flooding you may experience are found below.  Brief descriptions of some of the types of flooding you may experience in eastern New York and western New England are found below. More information about these and other flood hazards can be found on the NWS Flood Safety Website at www.floodsafety.noaa.gov.


Flash Flooding: Flash flooding is a rapid and extreme flow of high water into a normally dry area, or a rapid water level rise in a stream or creek above a predetermined flood level, beginning within six hours of the causative event (i.e. intense rainfall, dam failure, ice jam).


River Flooding: River flooding occurs when rivers rise and overflow their banks, inundating areas that are normally dry. The latest river forecasts for eastern New York and western New England can be found at our Advanced Hydrologic Prediction Service page at https://water.weather.gov/ahps2/index.php?wfo=aly.


Tropical Systems and Coastal Flooding: At any time of year, a storm from over the ocean can bring heavy precipitation to the U.S. coasts. Whether such a storm is tropical or not, prolonged periods of heavy precipitation can cause freshwater flooding in coastal areas, as well as further inland as the storm moves onshore. In addition to the freshwater flood threat, tropical systems and nor'easters can bring the threat of storm surge related coastal flooding.

 

Snowmelt: Flooding due to snowmelt most often occurs in the spring when warming temperatures quickly melt the snow. The water runs off the still partially frozen or already saturated ground into nearby streams and rivers, causing them to rapidly rise and sometimes overflow their banks.


Ice and Debris Jams: A backup of water into surrounding areas can occur when a river or stream is blocked by a build-up of ice or other debris.

 

Dam Break and Levee Failure: A break or failure can occur with little to no warning. Most often they are caused by water overtopping the structure, excessive seepage through the surrounding ground, or a structural failure.


Understanding the different flood hazards and knowing the actions to take before, during, and afterwards can help you protect your life, the lives of your loved ones, and your property.  Prepare now by visiting www.floodsafety.noaa.gov


Join us tomorrow for information on flood related services provided by the National Weather Service.