(Describer) In an animation, streams of light collide to create a globe filled with water. Title: Science Nation. Lightning flashes through dark clouds in a rain storm.

(male narrator) When severe weather is about to strike, we all want up-to-the-minute information. But the radar network called NEXRAD, that meteorologists depend on, has its limits. The biggest drawback: the equipment is typically spaced 100, even 200 miles apart.

(female) You have a radar, and the beam goes out.

(Describer) The bottom of the beam is horizontal.

As it gets further away from the radar, you can see there's this gap

(Describer) ...underneath.

because the earth curves away from the beam. And a lot of tornadoes actually happen in that gap.

(Describer) Barbara Philips:

That's one reason why the false alarm rate for tornadoes is almost 75% right now. The orange color is 90 mile an hour winds...

(Describer) She notes an orange blotch on a radar image.

(narrator) With support from the National Science Foundation, Brenda Philips co-directs CASA, the Center for Collaborative Adaptive Sensing of the Atmosphere. Engineers and scientists have developed and implemented a new generation of smaller, highly-capable radar systems designed to be spaced much closer together. The improvement is easy to see.

(Describer) She points out red and orange on CASA data that is missing NEXRAD data of the same area at the same time.

(female) This is the CASA data. Basically, it's this image right here is the tornado that's happening. When you see the picture here in NEXRAD, you know the tornado is happening, but you can't tell precisely where it's occurring.

(Describer) A funnel cloud touches the ground.

(narrator) From tornadoes to flash floods, the cities of Dallas and Fort Worth face more than their fair share of dangerous weather. So when the CASA team was looking for an urban area to test its system at the neighborhood level, the metroplex was a good fit. When we have events, we try to turn those around

(Describer) Tom Bradshaw, NWS:

and produce case studies to try to learn from what the CASA data showed us.

(Describer) Juan Ortiz:

(male) With smartphone technology and GPS we can give you the information where you are now so that you can make the right decisions to protect yourselves, as well as your family members.

(narrator) More accurate, localized forecasts can save businesses money as well as protect lives. The mayor of Midlothian, south of Dallas/Fort Worth, was happy to get his small town in on CASA. There's now a radar right at the police station.

(male) They're getting protection from adverse weather. Not just tornadoes, but ice, possibly give us ice, it'll give us rain, it'll give us all the major products that affect a city or a community or a region from a weather standpoint.

(female) Having the data, having an emergency manager or forecaster start to analyze it and see the benefits of it and translate that into something that could be lifesaving, I think that's the real excitement.

(narrator) Smaller, smarter radars, able to track dangerous weather street-to-street, that's the kind of early warning system I want protecting mi casa.

(Describer) A globe turns by the title.

For Science Nation, I'm Miles O'Brien.