How do you survive a flash flood? Keep an ax in the attic

Back-to-back flooding disasters in recent years — in Texas, New Mexico and Kentucky, among many others — have showed that preparing for flash flooding is a new necessity as the planet warms.

And there’s no more dangerous time for a flash flood than after dark; you can’t see the storm coming, and you can’t see the water rising. Worse, if it’s late enough, you’re not awake to hear the warnings.

So how do you stay safe?

Here’s what to do right now to help keep you and your loved ones safe before the next flash flood strikes.

Know your risk

The first thing you should do is figure out whether your home is in an area of flood risk. The best way to do that is to look at flood zone maps, which will show which areas will be dangerous when the water starts to rise.

Look up your address on the US Federal Emergency Management Agency’s flood mapping tool. Are there stripes or swaths of color over your home or neighborhood? If there are, you’re at some level of risk. If extreme flooding strikes, there’s a high chance you will be affected.

FirstStreet.org is another tool you can use to assess your risk. Just plug in your address to see how vulnerable your home or community is to floods, fires, wind and extreme heat. The site also includes projections of how those risks are expected to change in the coming decades, a useful reminder that the climate crisis is supercharging rainfall and driving up flood risk.

Stay informed

Flash flooding, by nature, is intense and sudden. You probably won’t have time to plan once a flash flood hits, so you need to know if the weather could turn foul before it happens and take the forecast seriously.

For starters, meteorologists are really good at getting the word out.

• Do you spend a lot of time on social media? Follow your local National Weather Service office and your favorite TV meteorologist there.

• Watch TV. We’re partial to CNN, of course, but local news is still one of the best ways to get weather warnings. Many stations also have their own weather apps.

• Sign up for severe weather alerts through a weather app. These will include more than just the most dire warnings; you can also get personalized forecasts and notifications for when meteorologists think conditions could get bad.

• Understand the alert lingo: A watch is issued when conditions are right for bad weather, but it hasn’t happened yet. A warning is issued when the severe weather is happening. An emergency is issued when things are really, really bad.

Don’t shut off your cell phone alerts

You know them when you hear them: those blaring emergency alerts that come out of your cell phone. Tornado; flash flooding; a missing child — all of these will trigger a Wireless Emergency Alert.

They may be loud and startling, but don’t turn them off. They might be the only line of defense between you and deadly weather when you’re fast asleep at 2 a.m.

Get a NOAA weather radio

You can’t watch TV when the power is out, and cell phone service isn’t guaranteed in an emergency. So when all else fails, a weather radio can make sure you still get the warning.

These devices stay silent until a serious alert is issued, then automatically turn on and tune in to broadcasts from the National Oceanic and Atmospheric Administration, which issues real-time weather alerts, including flood warnings.

Many models come equipped with flashlights and hand cranks to keep the battery charged. Some have solar panels.

These radios are also designed to wake you up in an emergency, just like a smoke alarm.

It doesn’t matter how fancy you want to get; the point is that they serve as a failsafe source of information and offer much-needed peace of mind, especially if you’re in a high-risk zone.

Have a plan

Alerts and information will only go so far if you don’t have a plan.

Evacuating early and moving to higher ground as soon as possible is essential.

Having a “go bag” prepared will also enable you to move quickly. FEMA recommends that you have at least a gallon of water per person per day for several days, as well as a multiple-day supply of nonperishable food, plus a flashlight, a first aid kit, batteries and basic sanitation items like antibacterial wipes and garbage bags. Keeping cash in there is also smart; if stores are open, don’t expect them to take credit cards if the power or internet are out.

Tips for when the water starts rising

Be prepared to get to higher ground on foot. Driving through high water can be deadly, so the “on foot” part is critical. Grab your emergency kit and head to higher ground on foot before high water hits your doorstep. Plan where that will be ahead of time.

Keep an ax in the attic. This sounds wild, but if the water is so high that you need to get into your attic, you’re going to need a way out. And that’s going to be straight up through the roof with an ax.

Invest in life jackets for the family. If the worst happens and you’re swept away by floodwater, a personal flotation device could save your life.

Never drive through flood water. It’s imperative not to get in your car in a flood, especially if you don’t know whether your escape route is in a flood zone. Two feet of water can float a car, and 6 inches of moving water can sweep you off your feet. If you find yourself in a car with floodwaters rising around you, get out immediately and get to high ground.

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