WICHITA, Kan. (AP) — Bone-chilling screams split the air.

Terrified voices shout “Jesus!” and “I love you!” to seek divine protection or share one final message.

The haunting audio of people taking last-moment shelter from tornadoes that devastated the Deep South and Joplin, Mo., last spring opens the storm spotter training presentation given this spring by the Wichita branch of the National Weather Service.

The sounds transport the audience back to the deadliest year for tornadoes in decades, shattering the illusion that the era of high death tolls from tornadoes had passed.

Last year saw 260 tornadoes strike the Deep South on April 27 — the most tornadoes ever recorded in a 24-hour period. Those tornadoes combined killed 320 people.

On May 22, an EF-5 tornado with wind speeds in excess of 200 mph demolished much of south Joplin, killing 158 people — the deadliest single tornado since 1947.

Every person heard on the audio opening the presentation had sought some form of shelter from the tornadoes that struck, said Chance Hayes, warning coordination meteorologist for the weather service’s Wichita branch.

Each of them managed to survive, Hayes said, but “some of them were in places they should not have been in” such as big-box stores or mobile homes.

“If they’re waiting for the sirens to sound, they have waited too long. They need to be prepared beforehand.”

Hayes was part of the weather service team that audited the watches and warnings issued from the Birmingham, Ala., branch to see what worked and what didn’t.

“In Alabama, those folks had a week’s worth of notification that the storms were going to occur,” Hayes said. “If they had no clue it was going to be a bad day, they were in a hole. They should have known that.”

Joplin was a different story, he said.

There was only a slight risk for severe weather issued that day by the Storm Prediction Center, but conditions rapidly became much more favorable for severe weather to occur as the day unfolded.

Even then, interviews conducted after the tornado hit showed residents had anywhere from two to nine alerts or “risk signals” that severe weather was imminent before they took shelter, Hayes said.

Risk signals could be anything from looking outside and seeing threatening clouds to an alert put out by weather radio or shared by a television meteorologist.

“The sirens were the first risk signal for most folks in Joplin,” Hayes said. “What they didn’t realize, however, was how serious it was.

“They had no clue.”

Hayes said he hopes residents will soon learn to take appropriate shelter after just two or three risk signals, such as a siren sounding and then a check of television or radio to confirm the immediacy of the threat.

In response to what happened last year, local weather officials are stressing awareness, escape routes and safety zones in this year’s storm spotter safety classes.

They know storm chasers and spotters aren’t the only people who come to the classes. Many are residents simply wanting to learn more about the weather.

If phone calls are any indication, crowds for this year’s classes will be larger than any in years, Butler County Emergency Management director Jim Schmidt said.

The classes for the Wichita area and southeast Kansas began last week and continue through early April.

It’s easier than ever for people to stay aware of dangerous weather approaching, Hayes said.

With weather radios, television stations, radio stations providing live coverage, social media and other sources - including the telephone and your own eyes - there’s no reason for people to be surprised by threatening storms.

The key is being alert and knowing where to go for shelter before the storm hits.

Weather officials are stressing a simple message for motorists driving into ugly-looking storms: Don’t.

If a storm has a blue-green tint, it’s likely loaded with heavy rain and hail.

If the storm stretches to the horizon and has clouds that bend like a bow at the front and look like a shelf, strong winds are approaching.

Dark blue patches in storms signify particularly heavy rain, which can be dangerous to drive in.

In such instances, Hayes said, it’s better to drive away from the storm or seek shelter in a building until the storm passes.

People who will be driving at night should check for watches or warnings before they leave, as well as radar covering their intended path to see if they’ll run into severe weather.

They can also monitor radar on their smartphones if they have one.