. >> every single volcanologist believe it's likely that katla will below and it has the potential to be 100 more times than this one. >> not making it any easier to get a clear picture this evening. the volcano even interrupted president obama's travel plans. he and other world leaders had to cancel plans to attend the state funeral of poland's president today because it was considered too risky to fly. the funeral went on in krakow with them and nbc's jim maceda was there. >> reporter: a week of mourning came down to this. a funeral service. the flag-draped coffins of presidents lech kaczynski and his wife, maria, were blessed during a high mass in the ancient capital of krakow. dignitaries packed the small church, mostly from central and eastern europe, they came by car or train. but others sent their regrets. presidents barack obama and nicolas sarkozy and german chancellor angela merkel among dozens unable to fly through the cloud of ash hanging over europe. one exception, russian president dmitry medvedev. kaczynski was a divisive figure often alienating allies, but today all po

even more troubling, scientists fear a more dangerous volcano, katla could erupt next. >> it's similar to the other volcano, in that it's capped by a large ice field or glacier. so we might expect katla to start out fairly explosively like this volcano did at the summit. >> reporter: there is no place on earth the ash is thicker than down this road. the restricted zone directly under the ice flow. deep inside the poisonous haze swans in a pond, horses in a pasture. life trapped inside this other worldly place. >> this is what it's like to live under the volcano. there's a loud crack of thunder. it's only 3:00 in the afternoon. it's bright sunshine a couple miles down the road, yet here, it's pitch black. look at the ash. >> this woman and her family remain held up inside their house like survivors of an apocalypse, living in some totally foreign world. yes, naturally we're concerned, she says, but hopefully this won't last long. but scientists have no idea of knowing exactly how long the eruption will continue. it's expected to last several months at least at a low level. the question

. >> what are the chances the seismic activity could trigger katla?his one has gone off three times and in all cases katla has done so, as well. >> that was chris jansing reporting. in an decision to the seismologists working on the ground there is a team in the air with a team of vol canologists checking on the plume and later today will move over north america. but it's not expected to hit the u.s. >>> a team of doctors and support staff from howard university hospital left today for nigeria. their flight was po postponed on friday because of that vol cane nick ash. the group plans to spend two weeks in nigeria providing free health care to thousands of peel there. that trip may be shortened because of the delay in getting there. >>> a 4-year-old girl and a woman have been pulled arrilive from the rubble five days after the earthquake hit china. the woman is in critical condition and the little girl is suffering from heart trauma. meanwhile, there are signs of recovery there. buddhist monks helped set up tents for many of the survivors. many had bee

what are the chances that the seismic activity underneath this volcano could trigger katla? >> the only thing that we know is that this one has gone off three times and in all cases katla has done so as well. >> reporter: in addition to seismologists, who are working on the ground right now, there is a plane up in the air with a team of volcanologiszs checking on that ash plume. later today, it is, indeed, going to move over north america, but is not expected to hit the u.s. matt? >> chris jansing in iceland for us. thank you so much. now the impact of all of this on air travel and what's being done to get thousands of stranded passengers home. dawna friesen has that part of the story. good morning to you. >> reporter: britain and parts of europe remain a no fly zone for the fifth straight day, there's growing anger, especially from the airlines, that the authorities may have overreacted and closed the skies unnecessarily. for a fifth day, iceland's volcano is creating havoc in the skies. more than 300 airports across britain and europe were closed over the weekend, more tha

right now, they're keeping an especially close eye on the much bigger katla.far, indications are good. >> there are lots of measurements, lots of instruments on that volcano, and there's absolutely no sign of it activating so far. >> reporter: but even with the most extensive testing, predicting when what a volcano will do after it erupts remains an inexact science. >> this is nature. we can't control it and we can only guess about what might be ahead of us. >> reporter: an educated guess with a lot at stake. chris jansing, nbc news, iceland. >>> that's "nbc nightly news" for this sunday.

we hear explosions from the vol contain pope anyway, being here on pop of katla, this coal volcano so many icelanders fear, frankly, it feels like we're in another world. doesn't feel like we're on earth. >> gary tuchman, going the work out there. >> up there a while now. has a place in iceland by now. doing great work. updates about all of that. >> can you pronounce -- >> eyjafjallajokull. >> you know he can. sorry. wanted to you say that one more time. >> we want to hear you say it all day long today. >> i had to do it all day long about two days before i got it. >> very rhythmic. >> totally wrong, by the way. >> thanks, t.j. >> see you. >> you nailed it. have a great day. thanks a lot. >>> a serious threat across parts of the south particular. the stage is set for what could be an extremely dangerous tornado outbreak today. watches and warnings already posted in so many states. the highest risk areas right now, live pictures of, right now of memphis, but mississippi, alabama. also in the bull's eye, and now looking at new orleans. they are also keeping a close watch of a potential

and the last time e-15 erupted, katla, c-k-a-t-l-a, also erupted and sometimes that can be a bigger eruptionimagine two simultaneously erupting and all of that ash flowing over europe? it could be months of travel interruptions, maybe even years, the last time the volcano e-15 erupted, it kept spewing ash for two years, candy. >> wow. the things that happen you never actually even thought about. let me ask you, we had the planes that took off for heathrow not knowing if they could land, a flight i'm not sure i'd be on. we are hearing that heathrow is open. are they landing? >> they are landing right now. heathrow did open up about an hour ago. and i can kind of show you what happened here. the map behind me timed out while i was standing here waiting to talk to you, so i can't show you what the planes are doing at this point in time. i don't have anybody helping me here. so, the planes are landing from heathrow and gatwick. it's kind of an odd time for planes to be landing there because, you know, it's almost, what, 11:00, midnight there, but they're getting planes in there anytime they can