Flash Flooding Is A Sudden Danger. Here's What You Should Do To Stay Safe.

Flash flooding is something you may not think about, but there are things you can do to keep yourself out of a dangerous situation next time a torrential downpour happens.

A flash flood is one that happens suddenly, usually in the span of an hour, but sometimes in just minutes.

It can happen when heavy rain falls over already soaked ground or mountainous terrain, turning usually placid creeks and streams into rushing torrents spilling out of their banks.

Underpasses and other low-lying areas of cities and towns can flood quickly when storm sewers can't drain water running off paved surfaces fast enough.

The most extreme flash flood events can be destructive and deadly, flooding homes and trapping motorists.

On August 21, 2021, catastrophic flash flooding triggered by a state record 20 inches of rain in just 24 hours killed 20, flooded over 700 homes and caused over $100 million damage in Waverly, Tennessee, and nearby communities.

Flooding claimed an average of 98 lives in the U.S. each year over the past 10 years, trailing only excessive heat, according to data from NOAA.

Summer is the peak time of year for flash floods in most of the U.S., due to slower-moving weather patterns, ample warm and humid air, and occasional tropical storms and hurricanes.

Flash floods can also occur in the absence of severe thunderstorms that might normally grab your attention, sometimes making them a bigger surprise.

For example, a cluster of non-severe thunderstorms dumped over 11 inches of rain in southern Arkansas on July 3, 2022.

Fortunately, there are steps you can take to be ready before and during a flash flood to stay out of danger.

Flood Prone Area?

While flooding can happen anywhere if it rains hard enough, knowing how flood-prone your area is a good first step.

Is your home near a creek, stream or a normally dry wash that floods?

If you don't know, check flood maps from FEMA or ask a neighbor that has lived there longer.

If you do live in an area more susceptible to flooding, know how to get to higher ground quickly in case of a flash flood. Gather some valuable belongings in a "go bag" in case you need to evacuate your home quickly.

Since regular homeowners insurance does not cover flooding, you may want to consider purchasing flood insurance.

Pay attention to roads that tend to flood in your area, particularly underpasses. Keep those in mind the next time a flash flood happens.

Be Weather Aware

The next step is simply to be aware of the forecast potential for flash flooding on any given day.

The easiest way to do that is to know if your local National Weather Service office issued a flood watch.

Similar to a watch for severe thunderstorms or tornadoes, the NWS issues flood watches when conditions are favorable for heavy rain that could trigger flash flooding in your area.

In The Weather Channel app, you'll see "Flood Watch" atop the screen below your current conditions. Tap on that and you can read the details from the NWS, including when the watch is in effect.

During a Flash Flood

Your local NWS office issues a flash flood warning when flash flooding is either already happening or expected to develop based on rainfall rates and radar trends.

Regardless of whether a warning is in effect at the time, avoid flooded areas.

Most importantly, never, ever, attempt to drive through a flooded stretch of road or drive around barriers saying a road is closed ahead due to flooding.

Over half of deaths in floods happen in vehicles, according to NOAA statistics.

The reason this is so dangerous is that it may be hard to judge how deep the water is, or whether flooding is hiding a washed-out section of road. Flooding can also be more difficult to spot at night.

It only takes about 1 foot of water to float many vehicles. Once your vehicle is floating, you have no control.

And if that water is moving, it will sweep your vehicle away, possibly tipping it on its side, flipping it, or smashing it against trees, bridges, rocks along a riverbank, or anything else in its way.

If you're stuck in your vehicle underwater, find a pocket of trapped air, usually against the rear window or roof. Roll a window down slowly, take a deep breath and be ready to swim.

If the window won't roll down, break the window with any blunt object, such as a Swiss Army knife.

Given the power of water to sweep vehicles away, don't attempt to walk through floodwater.

Just 6 inches of flowing water can knock you off your feet.

Flowing at just 6 mph, water exerts the same force per unit area as air blowing at EF5 tornado wind speeds, according to Greg Forbes, former severe weather expert at The Weather Channel. Water moving at 25 mph has the pressure equivalent of wind blowing at 790 mph, faster than the speed of sound.

Furthermore, flood water can contain debris, sharp objects, hazardous chemicals, sewage, even snakes and insects.

If you receive a flash flood emergency from the NWS, the situation is more dire.

These rarely-issued alerts indicate a flash flood poses a "severe threat to human life and catastrophic damage is happening or will happen soon," according to the NWS.

Such an alert was issued for the aforementioned deadly Tennessee flash flood of August 2021, flooding in the Northeast from the remnant of Ida in September 2021 and flooding from Hurricane Harvey in southeast Texas, among other events.

If you're in a flash flood emergency, you should avoid all travel unless you're escaping a flooding area or told to evacuate.

Flash floods can be as dangerous as tornadoes and severe thunderstorms.

Taking these steps before and during a flash flood should minimize your chances of being stuck in a flooded vehicle and could save your life in a more serious event.

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