GIS AND TORNADO SIRENS 2006 IRE NATIONAL CONFERENCE IN FORT WORTH

Sarah Okeson Journal Star Peoria, Ill.

sokeson@pjstar.com 309-686-3251

On May 10, 2003, a tornado with winds up to 200 mph hit South Pekin, a small village near Peoria, capping a week in which more than 300 tornadoes were reported across the Midwest. The Journal Star has mapping software, and I decided to use it to look at how prepared Peoria County was for a tornado. Here are some of the tools and sources I used in doing the story. GPS Device I wanted to look at how much of the county was within range of tornado sirens. I soon learned that sirens aren’t like houses with specific address. They’re often in fields or parks so it’s more accurate to plot their latitude and longitude. Some counties and municipalities know what latitude and longitude their sirens are at, so all you need to do is get the information and plot it in ArcGIS. Unfortunately, Peoria County didn’t have that information. I bought a GPS device so I could find the exact locations myself. People who hunt and fish frequently use GPS devices. You can buy a simple handheld one for about $100. Downloading Waypoints You’ll need an eTrex cable and another piece of software to import the coordinates from the GPS device to your computer. I used www.gpsu.co.uk which let me import the waypoints into my computer as a shapefile that I could use with ArcGIS. Once I had the locations of the tornado sirens I drew radii around them to show how far away the sound of the sirens could be heard. I compared the coverage area of the sirens to a map of the census blocks to see how much of the county’s population was covered by the sirens. I also mapped the locations of the county’s schools and nursing homes to see if any of them were outside the range of the sirens. Tornado Sites Here are some sources that helped me learn more about tornadoes. http://www4.ncdc.noaa.gov/cgi-win/wwcgi.dll?wwevent~storms. With this site, you can look at what tornadoes or other disasters have hit your state or county, if there were fatalities and what the property damage was. Alan Moller, who can be reached at Al.Moller@noaa.gov, is a senior weather forecaster with the National Weather Service in Fort Worth. http://www.nssl.noaa.gov/ National Severe Storms Laboratory in Norman, Okla. Harold Brooks, a research meteorologist, was very helpful and interesting. He can be reached at (405) 325-6083.

Newspaper: PJS Date: Sep 11, 2005

Day of Week: Sunday Edition: All Section: CITY

Page: A1 Length (in lines):

Headline: Peoria selected 'stormready' - With 17 tornado sirens, city one of 37 in Illinois to earn designation

Byline: SARAH OKESON Captions:

Published: LEFT: Julie Redenius comforts her daughter Linda, 6, on Sept. 14, 1965. The girl broke into tears when she found her mother's home at 1218 W. Blaine St. flattened by a tornado after walking home from school. Julie Redenius escaped the house through a back door but had to dig her way back in the front door to where two of her sons were trapped in the rubble.

ABOVE: Norwood School students line up outside their tornado-wrecked school along West Farmington Road in September 1965. The students were waiting for buses to take them to three churches serving as temporary classrooms. A portion of the school was severely damaged in the Sept. 14, 1965, tornado.

CAPTION: Peoria County sirens Keywords: weather

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PEORIA - As New Orleans grapples with the aftermath of Hurricane Katrina, Peoria is nearing the anniversary of the worst tornado to hit this community, and city and county planners are wondering if they are ready for a repeat.

Almost 40 years ago, on Sept. 14, 1965, an afternoon tornado injured 30 people and caused an estimated $2.5 million in damage as it left a seven-mile swath through Norwood, Bellevue and South Peoria.

The city had sirens, but the only advance warning of the tornado was the sound of the 150-plus mph winds. No one pushed the panic button to sound the sirens because the tornado wasn't spotted before it hit.

In the decades since then, the city and county have spent thousands of dollars installing a network of sirens - 17 in the city and 63 in the county outside Peoria - and plan to add more soon.

"We're always playing catchup," said Vicky Turner, the director of Peoria County's Emergency Services & Disaster Agency. "I know we'll never have the entire county covered. It's just too much to do."

But the National Weather Service thinks Peoria is adequately prepared for a tornado or other disaster. The city is one of 37 communities in Illinois and the only city in the Tri-County Area to be considered "storm ready" by the weather service.

In comparison, New Orleans, Bloomington-Normal, Springfield and Rockford weren't considered "storm ready" by the National Weather Service, although Champaign-Urbana, Carbondale and Aurora are.

"The National Weather Service is saying that this community is ready for natural disaster," said Chris Miller, warning

coordination meteorologist for the National Weather Service in Lincoln. "People in that community can rest assured that the emergency managers are prepared for it."

To be considered storm ready, communities must, among other things, have access to radar data, be able to alert residents of possible disasters that are coming and be prepared.

Weather forecasters disagree on the effectiveness of tornado sirens. Some say it's a mistake to rely too much on sirens.

"A siren is like a doorbell," said Miller. "If someone rings the doorbell, all you know is that someone is at the door. You don't know who they are or what they want."

But Alan Moller, a senior weather forecaster with the National Weather Service in Fort Worth, Texas, is an advocate for sirens.

"It's best to have a multiple warning system and not depend on just one thing," Moller said. "I think a lot of people think sirens are passe and low-tech, but I don't think there's anything wrong with that. Most people killed by tornadoes are outside or in mobile homes. Sirens reach people who have the greatest vulnerability."

The city's tornado sirens consist of white rotating horns that are mounted on 50-foot poles. The county's sirens are black cells stacked on top of each other on a pole. The more cells the siren has, the more powerful it is.

The sirens cover almost every part of the county's cities, marching north up Illinois Route 29, south on U.S. Route 24 and west on U.S. Route 150.

Planners decide where sirens should go by looking where people are moving and how close the other sirens are. Depending on the make and size of the siren, it can be heard anywhere from 0.4 to 2 miles away.

The sirens for the city and county cover census blocks for all but about 5,400 people in the county, or about 3 percent of Peoria County residents, according to a computer analysis of the county sirens and 2000 census data.

On the first Tuesday of every month, city ESDA Planner Dwain Deppolder takes to his car as the city tests its sirens, listening as the warning system wails and trying to spot any neighborhoods that can't hear them.

In the early 1990s, the city upgraded its sirens, reversing an earlier decision to scrap the 1960s-era system after public outcry. The county has bought new sirens with money from a public safety sales tax that voters approved in 1996.

Tornadoes are to the Midwest what hurricanes are to Florida and Louisiana, but for about 70 years, from the late 1880s to 1952, government weather forecasters weren't even allowed to use the word "tornado" in a weather forecast. That meant people often didn't know about approaching storms in time to take shelter.

The man in charge of weather forecasting in the late 1880s, Gustavus Henrichs, was from Iowa, and he didn't like the term.

"He believed it was ludicrous to think there were as many as 25 tornadoes in the United States a year," said Harold Brooks, a research meteorologist with the National Severe Storms Laboratory in Norman, Okla. "He was concerned that if people thought there were a lot of tornadoes they might not want to move to Iowa. That ban was in place for a long time."

It was in place on March 18, 1925, when the Tri-State tornado was on the ground for more than three hours, passing over southeast Missouri, southern Illinois, and southwest Indiana, killing 695 people and destroying 15,000 homes.

Tornado historians speculate that increased awareness about tornadoes after the Tri-State tornado contributed to a steady decline in the fatality rate.

In 1948, two men at an Air Force base in Oklahoma issued the first tornado forecast. Four years later, the U.S. Weather Bureau began the first public severe storm forecasting service.

The last single tornado to kill 100 or more people in the United States was the Flint, Mich., tornado of June 8, 1953, that killed 116 people. Fourteen tornadoes have hit Peoria County since 1950, including the 1965 twister, according to the National Weather Service. None of the twisters have killed anybody.

As Peoria waits to see if refugees from Hurricane Katrina will arrive here en masse, local emergency workers are working with the local Red Cross chapter and The Salvation Army to be ready to house hundreds of people.

Peoria County Administrator Patrick Urich said it's good practice for how the county could handle a disaster here.

"We've got to make sure we have plans drawn up for all to see," Urich said. "What's being afforded by this opportunity is to see how this works in action."