March 25 through March 31 is Flood Safety Awareness Week in Eastern Washington. Each day during the awareness week the National Weather Service will feature information about a different flood related topic.

Today’s Topic: Flash Floods

Flash flooding: flash floods are exactly what the name suggests: floods that happen in a flash! Causes of flash flooding include heavy rain, ice or debris jams, and levee or dam failure. These floods exhibit a rapid rise of water over low-lying areas. There are many reasons that flash floods occur, but one of the most common is the result of heavy rainfall from thunderstorms. These sudden downpours can rapidly change the water levels in a stream or creek and turn small waterways into violent, raging rivers. Urban areas are especially prone to flash floods due to the large amounts of concrete and asphalt surfaces that do not allow water to penetrate into the soil easily.

Burn scars are prone to flash floods as well. Wildfires burn away the vegetation of an area, leaving behind bare ground that tends to repel water. When rain falls, it runs off a burn scar more quickly towards a low lying area, sometimes carrying branches, soil and other debris along with it. Without vegetation to hold the soil in place, flooding can produce mud and debris flows.

It’s important to avoid low lying areas and storm drains when heavy rain is in the area. Remember, Turn Around, Don’t Drown!

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