A Better Way to Track Tornadoes
Credit: Lori Mehmen / AP

Last year, six of the most intense tornadoes ever seen – twisters with the power to send buildings flying – touched down in the United States. That's more than in the past 10 years combined. This year's tornado count could be on track to be another record-setter. Forty people died in early March, when over 50 tornadoes struck the South and Midwest. In April, storms tore through Dallas–Fort Worth, leaving disaster zones in three counties. Current research shows only possible links between climate change and increased tornado activity. But one thing is clear: Over the past three years, tornado season has started earlier, with a rise in deaths and property loss. Tornado-warning technology, meanwhile, is stuck in the past.

The U.S. tornado-warning system now gives an average warning time of 13 minutes, with a three-in-four false-alarm rate. The system works like this: A network of 33 ground-based radars read wind speed and direction. If they detect tornado conditions – fast bands of wind in an unstable atmosphere – the National Weather Service (NWS) issues a "watch." Meteorologists then turn their attention to a more advanced detection system called Nexrad. When they see the signature spin of a twister, a "warning" is issued: Sirens are activated, a ticker runs on local TV, and radios advise people to seek shelter.

Another, more effective radar defense, called CASA, is being tested now. CASA consists of small, low-cost stations that provide extra coverage in high-risk areas. The images CASA beams back to meteorologists are much clearer than Nexrad's, decreasing false warnings and improving lead times by 25 percent. Similar, but far more expensive, systems also being tested now have the potential to double that.

CASA has already saved lives. On the heels of last year's catastrophic tornado in Joplin, Missouri, which killed 161 people and caused nearly $3 billion in damage, local emergency manager Lee Kuhlman was facing a huge twister headed for Newcastle, Oklahoma. Using CASA, Kuhlman says, "I could clearly see the funnel of the tornado," unlike with the Nexrad system, which is only capable of depicting the weather as mile-size pixels. While waiting for the Nexrad computers to refresh, he turned to CASA and saw the tornado change direction and head for a team of EMS workers in the field. Due to heavy rain, the workers couldn't see the funnel. "They wouldn't have known what was coming until it was too late," says Kuhlman.

If such upgrades work this well, why aren't they rolled out everywhere? The problem, as with most government services these days, is funding. After Joplin, President Obama warned against cuts that "might compromise the National Weather Service." This next budget, however, called for a $39 million reduction in NWS funding for 2013, which won't leave enough resources to operate the current system, let alone upgrade it. "People will die if these cuts are made," says Dan Sobien, president of the NWS Employees Organization. "Why can we afford around $40 million to fly the Blue Angels but not to save people's lives?"

With Washington's support in question, at-risk communities have begun constructing their own tornado defenses. A mix of municipal money and private grants is paying for four eight-foot-diameter radar globes in Dallas–Fort Worth. CASA will soon be operational, and by fall 2013, the number of radars will double. Juan Ortiz, the emergency management coordinator in Fort Worth, thinks the risk of waiting for the federal government far outweighs the cost to the community to fund CASA. If a truly violent tornado like the one that hit Joplin strikes the Dallas suburbs, the death toll could be huge – up to 30,000.

While Dallas and Fort Worth will soon have state-of-the-art radar, the rest of the country will have to make do with the unraveling safety net of the NWS. "We don't need to wait 20 or 30 years for the federal government to bring CASA online," says Ortiz. "We want to start saving lives and protecting property today."