tonight on "nightline" -- direct hit. a colossal tornado going almost 200 miles an hour rips through missouri. >> oh, gosh, that is a monster tornado. >> plunging one town into a terrifying nightmare. [ screaming ] >> and when the light returned, scenes of breathtaking destruction. an american tragedy. hundreds are injured and more than 100 are dead, including at a hospital, a home depot and a walmart. tonight at least 17 have been found alive. others are still believed to be trapped. and more to come? as rescuers race to locate survivors with the skies still in turmoil, meteorologists warn of more tornadoes to come across the country. we talk to the deputy director

of fema about what to do in case the worst strikes. a special edition of "nightline" begins right now. good evening, i'm terry moran. walking around joplin tonight is just an ominous experience. this is a blasted landscape. mile after mile of it. the trees sheared off with tremendous violence. houses torn apart and crushed. cars wrecked as far as the eye can see. and the storms are still coming. the night sky will just open up and the rains pour down, drenching the ruins. this was one of the deadliest tornadoes in the history of the united states. more than 100 souls have been lost. and abc's josh elliott spent the day in this devastated

community, with the first responders searching for survivors. >> reporter: last night, just before dinner, the town of joplin, missouri, was hit with this. what we now know to be the deadliest u.s. tornado since 1953. >> monster tornado. >> reporter: some residents were given up to 24 minutes warning. >> get the sirens going. i'm telling you. >> reporter: with the tornado traveling nearly 200 miles an hour, not nearly enough time. >> tornado's right over here. >> look at all the debris. >> be careful. oh, gosh. look at the telephone pole. >> i know. >> oh, my gosh. [ screaming ] >> reporter: at this convenance store, you can hear children screaming for their mothers and utter chaos as the tornado hits. [ screaming ]

>> reporter: the tornado covered a swath one mile by four miles wide. >> oh, i got lightning. >> there's the tornado right there in front of us. >> reporter: at st. john's hospital, they declared a condition gray. patients, relatives and staff instructed to leave their rooms to take cover in protected areas. later, gurneys and wheelchairs were tossed hundreds of yards. and medical personnel loaded patients on the backs of trucks to take them to safer locations. holding i.v. poles by hand. in the end, at least five patients and one visitor inside the hospital died. sheila and mark harrington were inside the emergency room when it happened. >> there was no light and we have very little flashlights in the debris of everybody in there. they were screaming and looking for their loved ones and saying that they couldn't find them and they wanted someone to help them and it was total chaos. the nurses was yelling.

i've never seen a tornado before. and we heard other nurses saying get away from the windows. >> reporter: rod pace, one of the medical flight managers, described to diane sawyer how he actually held on to a door inside the building as it tore his hospital apart. >> we were holding the door closed. we were trying to hold the door closed. it felt like the door would move. i've heard people talk about a building and how it breathes when it's on fire. >> right. >> it felt like that building was breathing and that door would move in and out. >> reporter: and carol buck was at home when disaster struck. >> we held our heads down. we didn't say too much. you could see things flying. coming in. the roof caving in. bricks flying from the hot fireplace. >> reporter: marie colby couldn't believe her eyes. >> you could see all the stuff flying through the air. big, huge chunks hitting the car. and they we saw a semitruck in front of us flip over and

another one up and over a little ways get picked up, thrown in ]> the air and actually tossed over into the ditch. >> reporter: but no one knew the enormity of the destruction till daybreak. well over 100 and counting among the confirmed dead. six miles of debris. more than 2,000 buildings damaged.xd to give you an idea of the path and the power of this tornado, take a look at what it did to a massive chunk of the roof of this walmart. just lifted it completely off. but then look at the incredible swath that it cut. some three to four miles. in the tattered distance, that tiny little building is, in fact, the seven story st. john's hospital. destroyed cars lined streets. roofs torn from homes and buildings. leading to a facebook page created for people looking for information about lost loved ones. governor nixon urged people to focus on saving those who were possibly still trapped in that debris. >> i want to focus on the fact we believe there are still rescues out there and we want to support the men and women that

are on the ground out there literally going foot by foot, searching for folks. >> reporter: doug westhoff's team, missouri task force one, is the team in charge of these efforts. >> just a whopper of a twister, this is just incredible damage. >> reporter: he's worked search and rescue for over three decades. he's seen september 11th and hurricane katrina. >> it's mother nature. we don't control it. we just react to it and do the best we can with it. >> reporter: doug and his team of 80, many of whom are volunteer, spent most of the day scouring stores like this walmart for survivors. we were able to get inside and saw the scope of the damage for ourselves. this section of this massive chain store had its roof torn off as the twister made its way through. as you can see, also reducing its outer wall to mere pieces of rubble. inside right now, the search and rescue workers are making their way, aisle by aisle, on the off chance anyone is still trapped in here alive. when we met them, search and

rescue worker erin and her dog pick had been on the job for roughly 20 hours. we're about 18 hours in. how much longer will your team be at it? >> we'll be at it until they tell us we don't need to be here any more and every single person is accounted for. >> reporter: across the street at the home depot, rescue workers did find eight people. seven were alive. one was killed by the storm. they aren't done searching. >> you were over in that far corner. can we go inside and do some more sections here? >> reporter: gary england believes his brother is still inside. he found his truck in the parking lot. >> we haven't found him yet. we'll keep looking. we'll be out here till we find him. >> reporter: but dave westhoff captured the essence of this close-knit town the best. >> you know, we are missourians and we take care of our own and this is a strike, as you say, in our own backyard. our hearts say, get down here and do what we can to help the folks in this part of the state. and we pull together as a group and do the best we can for them.

>> reporter: josh, you've been out in it all day and the devastation in this weather. with the first responders, search and rescue. what did you see? what was that like? >> a relentless sense of perspective. every time you wait to become inured to what you're seeing, you look down another city block and you find yourself thinking, oh, my god, look at that. and it's like that over and over and over again. we were out with the first responders and the search and rescue teams. and if you feel yourself lagging, if you think, wow, it's been a long day for me, you look at them, they started before we did. they'll be working through these horrific conditions all night, well into tomorrow. they're going to work until they drop. we heard often today that everybody who really responded, a lot of them were missourians and they really have a sense that this happened in their backyard and they're here to do whatever they can. but if you were at ground zero or at hurricane katrina, if you saw pictures of banda aceh, that's what we're talking about here.

it is a staggering thing. and we arrived in the darkness. and when sun -- when day broke today, it took your brett away. >> and took the breath away of some first responders who are veterans of tornado alley, who have seen a lot of devastation. >> we talked to some who have been on the job for over three decades and said this is as bad as they've ever seen it. they were speaking in euphemism, perhaps trying to take some of the sting out of it. we asked them, how do you compartmentalize it, how do you process it? how do you deal with the grisly discoveries you make, perhaps hour by hour, they work house to house to house, and they struggle, especially considering these are their brothers and sisters. >> and the people in this community or what was this community also pitching in. >> and i think that's a real point to make. so many people caught themselves talking about of the place where they work. well, used to work. the place where i live. well, used to live. and watching people just start

to process it was a very tough thing today. >> because it's gone. >> it's all gone. >> all right, josh, thanks very much. get dry. >> you bet, terry. >> all right, thanks. ♪ professional driver on a closed course. ♪ do not attempt at home. always wear your seat belt. ♪ and please drive responsibly. [ male announcer ] it's the most fun you can legally have. see your authorized mercedes-benz dealer for exceptional offers on the c-class. that's how it is with alzheimer's disease. she needs help from me. and her medication.

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if it seems like this has been a terrible year for tornados, that's because it has. there have been more than 480 tornado-related deaths in the u.s. in 2011. that's eight times the average over the past three years.

experts say death toll from a storm like this is so random it depends on whether the tornado hits a populated area or not. here in joplin, many factors came together. as sam champion reports. >> reporter: here in joplin, missouri, thunderstorms and high winds swept through once again. not 24 hours after the massive tornado ripped through the town -- >> there's the tornado right there in front of us. >> reporter: and new details about that deadly tornado are now emerging. it was an incredibly fast-forming supercell created by the clash of warm moist air and a cold front. the unstable result, a twister. according to the national weather service, it went from a funnel cloud to a very large and extremely powerful tornado in under ten minutes. we now know it was a massive ef-4 tornado, meaning registered winds were over 190 miles an hour. the giant was three quarters of a mile wide as it touched down at 5:41 local time. residents here in joplin were

given about 24 minutes notice a tornado was headed their way but for many that wasn't enough. 75% of the town was damaged by that tornado. and we lost at least 115 lives. even veteran storm chasers say they haven't seen anything like this. >> the thing that was the most amazing about this tornado was the sheer size of the tornado and how fast it moved through the city of joplin. it was on -- my speeds were up to 45, 50 on the south side of town and i could not keep up with the tornado. it was actually outrunning me. the tornado was literally probably in excess of 50 miles an hour. >> reporter: as search and rescue teams continue to work throughout the night looking for any survivors, many are wondering just what's going on this year when it comes to this deadly string of severe thunderstorms. last month, 875 confirmed tornadoes was an all-time record for the month of april. in that month, 24 lives were lost during a series of storms in north carolina. and then came the deadly outbreaks that devastated parts

of tuscaloosa, alabama, leaving a death toll that reached beyond 300. so far this year there have been over 450 reported tornado deaths, making 2011 already the ninth deadliest tornado season since 1875. so what's happening? there's a persistent pattern of colder than normal air in the west that's being driven by a powerful jet stream. and colliding with warm, humid record heat in the south. this results in an extremely unstable and favorable pattern for severe thunderstorms and tornadoes to develop over and over and over. >> this year has really been just the perfect year for tornados. >> climatologist heidi cullen writes about global warming but she says you can't pin these tornadoes directly on climate change. >> extreme events like droughts, heat waves, wildfires, those are phenomena we very much expect to see more of as we move into a warmer world. >> yet, still we don't know whether or not tornadoes are

being lumped into that extreme weather? >> it's one of those things where we just don't have enough data to really make the case. >> as for the unusually high number of dets, experts say tornadoes this year seem to have struck very populated areas, increasing the chances for fatalities. >> we're getting a two-dimensional picture of whatever is out there. we're able to detect differences in precipitation like rain, like hail, like even tornado debris. >> tornado detection technology is improving. new dual polarity raid daughter shows nonprecipitation movement that can signal the existence of a tornado immediately. >> let's say, for example, it's nighttime, you know, storm spotters may still be out there but because it's dark they're probably not going to see a tornado. the radar doesn't care if it's day or night. as long as there is debris, airborne debris that a tornado has lifted and is swirling around, tiny bits of debris -- leaves, twigs -- the radar's going to be able to see it where a spotter may not be able to see it. >> what is clear in joplin is

that no amount of warning could have prevented utter destruction we see here tonight. there is no sign of relief. with another powerful storm system moving into the plains and the midwest by tomorrow. it guarantees more severe weather and looks more and more like another tornado outbreak in the same areas. for "nightline," i'm sam champion in joplin, missouri. missouri. well, hotels k can't fill every room every day. like this one. and this one. and oops, my bad. so, they give expedia ginormous discounts with these: unpublished rates. which means i get an even more rockin' hotel, for less. my brain didn't even break a sweat. where you book matters. expedia. i really didn't see it coming. i didn't realize i was drifting into the other lane. [ kim ] i was literally falling asleep at the wheel. it got my attention, telling me that i wasn't paying attention.

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when disaster strikes in america, neighbors help neighbors but they're going to need a lot more than that. that's when government and aid workers step in and they have their work cut out for them in joplin. earlier, i spoke with the deputy director of fema. when you arrived here this morning and saw this devastation, mile after mile of

it, what was your reaction? >> the first thing i noticed was all the first responders. the police officers. the firefighters. the emts. the heroic work they were doing, pulling survivors out of the rubble. also neighbor helping neighbor, pulling each other out of the rubble. the resiliency of this community has been unbelievable. >> now fema's here, the federal government's here. what are you going to do, what is the first priority? >> we have resources we started to roll in here at the request the governor. anything they need, we're going to be there. the president sent me down here first thing this morning to make sure that the full family of the federal government is going to be here to support whatever's needed. we're not here just for a couple of days, a couple of weeks, we're going to be here for months. >> what kind of help does the government have for people? >> the one thing that's important to realize, this isn't just fema, it's the entire team. it's the federal, state, local

government. it's also the tremendous work the faith-based community has been doing. it's also the work of the private sector. nongovernmental operations such as the red cross, the salvation army. we're going to be there to help them. it has to be a team effort. that's how we'll proceed with it. >> they had a warning. 24 minutes warning here. for people who hear a tornado warning around the country what do you want them to do? >> one of the things we want people to do is get low, drop, cover and hold on. if they can go into a basement, or don't have a basement, get a room, in a closet. the best place they can be is down, if they can cover up. really just to get underneath somewhere, go into a basement in a room, that's the best thing. >> the search and rescue operation continues tomorrow first light? >> the search and rescue will continue. they had 400 firefighters here. they have another batch ready to come in to continue the search and rescue. just the work that the local first responders have don