. >> reporter: jim samaras takes solace that his brother and nephew and their colleague died doing what at that. that was beautiful. >> reporter: for tim, it was a wide-eyed enthusiastic kind of passion that fuelled every chase. >> i don't know how many storms i have seen in my lifetime. but every one of them i still get pretty excited. the little boy in me wants to come out here and just watch and stare. >> reporter: for "nightline" i'm ginger zee. >> coming up next, a great hunter becomes the hunted. inside the quest to save the elusive snow leopard. [ lighter flicking ] [ male announcer ] you've reached the age where giving up isn't who you are. ♪ this is the age of knowing how to make things happen. so, why let erectile dysfunction get in your way? talk to your doctor about viagra. 20 million men already have. ask your doctor if your heart is healthy enough for sex. do not take viagra if you take nitrates for chest pain; it may cause an unsafe drop in blood pressure. side effects include headache, flushing, upset stomach, and abnormal vision. to avoid long-term injury, seek immediat

jim samaras is tim's brother. >> his goal was actually saving lives through the technology that he's been able to develop. >> reporter: meteorologists tracking the tornado's path say it appears the three men may have been unable to escape when friday's twister after cutting a fairly straight path made a sudden turn north. kwtv meteorologist and storm chaser david payne was out following the same tornado friday from the opposite side. >> that tornado made a swing to the north, and when that happens sometimes, it can strengthen and become a bigger, more violent tornado. you don't have any time. and if the roads are all jammed up, then there's nowhere to go. >> reporter: and if you're in the wrong spot at this time, you can't escape. >> you can't escape. you become part of the tornado. and if that happens, it's a bad, bad deal. >> reporter: samaras tracked tornadoes for 30 years and was considered highly experienced and careful. his brother says it gives everyone an eye for pause. >> it's an eye opener for veterans out there. it doesn't matter how many you've seen or how many you've cha

jim samaras is tim's brother. >> his goal was actually saving lives, through the technology that he's been able to develop. >> reporter: meteorologists tracking the tornado's path says it appears the three men may have been unable to escape when friday's twister, after cutting a fairly straight path, made a sudden turn north. kwtv meteorologist and storm chaser david payne was out following the same tornado friday from the opposite side. >> that tornado made a swing to the north and when that happens, sometimes, it can strengthen, it can become a bigger, more violent tornado you don't have any time. and if the roads are all jammed up, there is no where to go. >> reporter: and if are you in the wrong spot at that time, you can't escape. >> you can't escape. and you basically become part of the tornado. and if that happens, it is a bad, bad deal. >> reporter: samaras tracked tornadoes for 30 years and was considered highly experienced and careful. payne says his death gives everyone pause. >> i think it's kind of an eye opener even to the veterans, you know, like myself, the guys out th