Weather Warnings Can Save Lives. Here’s What Makes Them Effective.

Severe weather can happen any day of the year. If you are in its path, you’ll probably get a warning in the form of a shrill alarm on your cellphone or text scrolling across the TV screen.

These messages are carefully crafted to make sure you have time to seek shelter before it’s too late, which could unnecessarily put you, or emergency medical workers, in harm’s way.

But what actually causes people to respond to these warnings?

It’s something scientists learn more about every day. Here’s how it works and how you might convince your uncle, for instance, that he really does need to evacuate ahead of the next hurricane.

An effective warning is specific.

People often look for an indication that they will be directly affected by a storm, said Kathleen Sherman-Morris, a professor of meteorology and climatology at Mississippi State University. This means it is important for a warning to be more specific than, for example, saying that a tornado is headed toward Eastern Tennessee.

“A lot of times you’ll hear people on TV pointing out communities and roads and landmarks,” Professor Sherman-Morris said. “Those kinds of things are very important to help people understand that it’s coming close to them.”

If you are trying to convince a skeptical relative about incoming danger, it will help to be specific in your messaging, too (assuming they trust you). Tell them about a local landmark that could be affected, based on the forecast, or when the storm is expected to be at its worst where they live. If you both know someone in the area who has already experienced problems because of the storm or posted about its destruction online, it could also help to relay that information.

Why do some people hesitate or ignore warnings?

Some people will go to a tornado shelter as soon as a warning is issued. Others might get the warning, then take a few minutes to read about the storm online, see what the television says and talk to family and friends before sheltering. “Different people need different levels of confirmation,” Professor Sherman-Morris said.

Those who do not act because they believe they will be fine, despite the warnings are a minority.

To emphasize the potential danger, emergency managers will sometimes use shocking or jarring language, said Amber Silver, assistant professor in the department of emergency management and homeland security at the University at Albany.

In 2017, Patrick Rios, then the mayor pro tem of Rockport, Texas, told people who chose not to evacuate before Hurricane Harvey to use a permanent marker to write their names and Social Security numbers on their arms in case they died.

Alerts do not reach everyone.

The National Weather Service provides alerts in English and Spanish, which can limit communications with people who primarily speak other languages.

In September 2021, heavy flooding in New York City spotlighted the challenges faced by people who are not fluent in English. Many of the 13 New York City residents who died spoke limited English and may not have received or understood the warnings sent before the storm.

The messages can also be incomprehensible to people with cognition issues, or inaccessible to those who cannot afford computers or TVs.

There is specialized alert equipment for people who are blind, deaf or hard of hearing, but the most common sources of information, such as TV broadcasts, could also be made more accessible by using more descriptive and specific information, according to a 2020 study published in the International Journal of Disaster Risk Reduction.

That is why a key part of the warning process is family, friends and the community, not just the technology, said Kim Klockow-McClain, a senior social scientist at the National Weather Service who visits places that have experienced severe weather events and talks to residents about how warnings influenced their actions. She said good warning systems involve “a set of organizations of people who are all coming together to alert each other that something is going on.”

It is not always easy to leave.

Once people get a warning, it can still be challenging for them to act on it.

First, shelter is not a given. People who live in mobile homes, which are not typically safe shelter in severe weather, must make a decision to find a safe place before a warning is issued, because it can quickly become too dangerous to travel. And not everyone has a social network that can help them find somewhere safe.

People who need to evacuate their homes but have mobility challenges also face barriers responding to alerts. A 2002 study published in the journal Natural Hazards Review found that households that included people with mobility challenges were less likely to evacuate than those without.

For others, transportation, food and hotels during an evacuation can be too expensive.

The National Weather Service and its parent agency, the National Oceanic and Atmospheric Administration, are working to improve how underserved populations get information in emergencies, Ms. Klockow-McClain said. The agency’s VORTEX program is conducting field research and gathering data to ultimately give meteorologists in the Southeast more lead time in recognizing tornadoes that are embedded in a line of storms, potentially buying time for issuing alerts and circulating other practical information, such as shelter locations.

Ms. Klockow-McClain said that people with fewer resources often “shoulder the burden” and account for a disproportionate share of fatalities.

How do I get a severe weather warning?

Warnings can be issued for events including dangerous cold, heat, wind and rain.

Some alerts, such as tornado warnings, demand instant action. Others, such as tornado watches, indicate that you should prepare in case things escalate.

Get alerts from at least two places.

Before a storm happens, people should check that they can receive alerts from two sources, such as a cellphone and the radio. Your cellphone should automatically receive severe weather warnings. Many cities and states also have their own cellphone alert systems.

Local meteorologists can also be a great resource because they are familiar with the community, Professor Sherman-Morris said.

How can alerts be improved?

Ms. Klockow-McClain of the Weather Service is pushing for technology that could better address the gray area between a watch and a warning, so people can make the best decisions possible under the circumstances.

“It actually is mind-boggling how much we can get from models now,” she said. “And the challenge is really giving you the right slices of all of that to make sense of what’s going on.”

The Weather Service is also trying to learn the best way to get messages to communities, such as those where English is not the predominant language. This means identifying what people and resources a community turns to for its information.

Ten years from now, the way we receive alerts could look “very, very different,” Ms. Klockow-McClain said.

“That’s our hope, is that it will.”