Severe Weather Awareness Week: The Dangers of Flooding

During a thunderstorm, many people are understandably scared of the electrical current flowing through lightning, and even the sonic boom that creates the bellowing clap of thunder.

"Moores Mill Road! In 22 years I've never seen it flood like this, and to be on Christmas! Alabama weather is awful!" (Photo: Leighann Sharpe, Christmas 2015)

"Moores Mill Road! In 22 years I've never seen it flood like this, and to be on Christmas! Alabama weather is awful!" (Photo: Leighann Sharpe, Christmas 2015)

But according to the National Weather Service and the Centers for Disease Control, floodwaters claim more lives than any other thunderstorm-related hazard. In fact, it is the second most deadly weather event across the nation (heat-related fatalities ranks first).

Flooding is an overflow or over-abundance of water accumulating on land that is normally dry. Floods can happen during a period of intense rainfall (ie, a heavy downpour that lasts for hours); steady rainfall that lasts for several days; when snow melts too quickly; or when a dam or levee breaks.

A flash flood occurs when floodwaters accumulate quickly and with little to no warning. Flash floods are particularly dangerous because they can generate a large amount of water in a short amount of time, often in creeks and riverbeds that could overflow into homes as well as roadways.

"Over half of all flood-related drownings occur when a vehicle is driven into hazardous floodwater," explains the NWS on their Turn Around Don't Drown flood safety page. "The next highest percentage of flood-related deaths is due to walking into or near floodwaters...Many of the deaths occur in automobiles as they are swept downstream."

Hole left in Danville Road by Thursday's flash flooding. (Photo: Al Whitaker, WHNT News 19)

Hole left in Danville Road by flash flooding. (Photo: Al Whitaker, WHNT News 19)

Keep the following facts in mind the next time you encounter flood waters:

  • It only takes 6 inches of swiftly moving water to knock over an adult
  • It only takes 12 inches of rushing water to carry away a small car
  • It only takes 2 feet of rushing water to carry away even the heaviest of vehicles
  • The power of the water is so strong that it can wash away the road beneath it, even if it looks like the water is calm

Remember: Even if floodwaters do not sweep away your vehicle, water entering the engine could cause it to stall, creating a hazardous situation in which you cannot move due to a stalled vehicle.

(Source: NOAA/NWS)

Flood safety: How to protect yourself during a flood

Flood alerts come in various forms, including but not limited to:

  • Flood Advisory
  • Flood Watch
  • Flood Warning
  • Flash Flood Watch
  • Flash Flood Warning

A flood advisory is issued when a flood event warrants notification due to significant disruption or inconvenience, but is less urgent than a warning.

flood watch is issued when conditions are favorable for flooding to occur in the short-term future. In this case, the watch is typically issued several hours to even days ahead of the onset of the flooding event.

flood warning is issued when floodwaters may pose a serious threat to life or property. A flood warning may be issued several hours to even days in advance of the onset of flooding. Flooding that occurs near a river usually contain river stage (ie, crest level) forecasts.

Whirlpool from floodwaters draining into a culvert under Tunsel road in Hartselle, Al

Whirlpool from floodwaters draining into a culvert under Tunsel Road in Hartselle, Alabama on Christmas Day 2015. (Photo: WHNT News 19)

flash flood watch is issued when conditions are favorable for flash flooding, and it can be issued several hours to even a few days ahead of time.

flash flood warning is issued when flash flooding is occurring or is about to occur. Flash flood warnings are considered urgent messages since dangerous flooding can happen incredibly rapidly. Flash flood warnings are often issued minutes to hours before the onset of the flash flood.

During a flood or flash flood WATCH, be sure to monitor your weather radio or Live Alert 19 app for any changes in weather conditions. Gather your emergency kit and get ready to take action to head to safety; you should already have a place in mind to head to, and if not, determine where the closest shelter area would be located for your area in the event that you live or work in a flood zone or flood-prone area.

The valley (Ruth area) where my dad hunts...down Ruth Mountain. The sign says "One lane bridge" but the entire bridge, road, and land is under water." (Christmas Day 2015 from viewer "emh71784")

The valley (Ruth area) where my dad hunts...down Ruth Mountain. The sign says "One lane bridge" but the entire bridge, road, and land is under water." (Christmas Day 2015 from viewer "emh71784")

During a flood or flash flood WARNING, the time to act is NOW. If you are outdoors, head for higher ground immediately. If you are on the road and you encounter swiftly moving floodwater -- or even waters that look still but yet you can't see the road beneath it -- do not attempt to drive through the floodwater. Instead, turn around and either find a different route, or shelter in place at a safe building that is located in a higher elevation.

If you are indoors during a flash flood WARNING and your home or office located in the path of floodwaters, try to move to higher floors within the building. Do not attempt to wade through floodwaters, since hidden dangers (including live electrical wires, sewage, wildlife, object that could pin you underwater) may be lurking in the flood.

If you witness any damage due to flooding, wait until the danger passes and then snap a picture through the Live Alert 19 app (you can also email us a photo@whnt.com). Please be sure to include your name and city/town/location. Your damage reports help ensure that forecasters at the National Weather Service as well as at WHNT News 19 provide the most detailed record of what occurred from the flood, which helps improve our forecasting abilities for future storms.

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