In Hennepin County, outdoor warning sirens still key to delivering severe weather alerts

When a family of tornadoes roared across the Twin Cities on May 6, 1965, authorities sounded civil defense sirens to warn people to take cover.

It was a bold move that had never been tried before, and it worked.

"They got it," said Eric Waage, director of Hennepin County Emergency Management. "They took shelter. The sirens saved lives."

Once reserved to alert civilians to enemy military attacks, outdoor warning sirens remain a critical tool in warning the public of extremely large hail, destructive winds and tornadoes. On Thursday, sirens will blare at 1:45 p.m. and 6:45 p.m. as part of a statewide tornado drill to be held in conjunction with Severe Weather Awareness Week.

The drills, which will be canceled if there is severe weather, are meant to encourage people to think, "What would I do now?" Waage said.

Other activities to remind and educate people about what to do when severe weather strikes will be Monday through Friday.

From 1950 through 2020, Minnesota has averaged 29 tornadoes a year, according to the Minnesota State Climatology Office. While 77% of twisters in Minnesota occur during May, June and July, the violent spiral windstorms have been reported in every month of the year except January and February. In 2021, at least 16 tornadoes danced across Minnesota on Dec. 15, the latest date for a tornado ever reported in the state, records show.

Though none has been reported in Minnesota yet this year, there had been 519 nationwide as of Friday, nearly double the average at this point in the year, according to the National Weather Service Storm Prediction Center. Tornadoes already have led to 63 deaths this year, approaching the yearly nationwide average of 71.

The trend has Hennepin County officials fearing that 2023 could be an active summer locally. Urban areas are not immune, as shown by twisters that inflicted damage on north Little Rock, Ark., and other communities across the southern U.S. in recent weeks, Waage said.

In the past 50 years, more than 30 tornadoes have touched down in Hennepin County, including north Minneapolis in 2011 and Edina and south Minneapolis in 1981. In 1939, a storm raced from Medina to Anoka and became the namesake of the Anoka High School sports teams: the Tornadoes.

While the nearly 300 sirens in Hennepin County remain the most direct way to get the word out — warnings don't have to pass through media outlets before reaching the public — the county in recent years has invested heavily in technology to expand ways to alert residents of the state's most populous county, and fast.

"People don't pay attention as they used to," said Emily Jackson, a Hennepin County Emergency Management meteorologist. "They are not as weather aware."

A large section of the county's public works facility in Medina houses the Emergency Operations Center. The county has three meteorologists on staff to monitor weather conditions, and a network of 25 automated weather stations feeding them data. When strong storms develop, staff members come into the nerve center to monitor a bevy of radio frequencies, send out alerts to cell phones and on social media channels and even post messages on electronic highway billboards.

The county also holds annual training for severe weather reporting for staff and volunteer weather spotters and works in concert with the National Weather Service.

"We hope to provide even more accurate warnings," Waage said.

In addition to tornado warnings, Hennepin County sirens sound when hail 2 ¹⁄₂ inches or more in diameter is reported and when winds reach 80 mph or stronger.

That is one reason Hennepin County is among several agencies participating in Severe Weather Awareness Week. And the hope is residents, businesses and schools will participate, too.

Waage said all households should have a NOAA weather radio that broadcasts storm warnings and hazards instantly. Cell phones may not be the most reliable because they might not work in some buildings, he said.

"People need to have more than one method to be warned," Waage said.

That is why the tried-and-true siren will always sound when severe weather strikes — an official confirmation that "it's time to take protective action," Waage said.