Feed. This morning, how facebook is responding. Sight to behold. That is a ninehour flight sunrise right there. Every minute of it. Matt and al take in the Natural Beauty of new mexicos stunning white sands. The next stop on our celebration of 100 years of National Parks. Today, tuesday, may 10th, 2016. Announcer from nbc news, this is today with matt lauer and savannah guthrie, live from studio 1a in rockefeller plaza. Good morning, everybody. Welcome to a special split edition of today on a Tuesday Morning. Matt and al are at the breathtaking White Sands National monument. Natalie and i are camping out at studio 1a. Thank you for bringing us the star wars set. Yeah, it is. Its like something from another planet. It really is. Its going to be one of the most beautiful sights on this planet in about 30 minutes, when the sun comes up and hopefully warms things up around here. Thats right. And this is actually the star of this show. Its called gypsum, and its whats covering 275 square miles of incredible landscape. Were going to show you around the sights, the sounds. Which, by the way, there are few of. Perfectly quiet here. Al will take you deep underground to Carlsbad Caverns in a little while. Looking forward to that. Very cool. Well see you in a bit. Our top story, the powerful tornadoes that cut a path of destruction across the plains overnight. Nbcs Gabe Gutierrez is in wynnewood, oklahoma, 60 miles south of oklahoma city. Good morning. Savannah, good morning. This home obliterated, ripped from the foundation. Debris everywhere. At least two people were killed in oklahoma, including a man in his 70s. You dont often see the explosive power of a tornado outbreak quite like this. Reporter it is a rare, intense glimpse at natures fury. A deadly, monster tornado, almost a mile wide, captured up close on camera, chewing through everything in its path. This morning, wynnewood, oklahoma, is assessing the damage. No structure spared. Brick homes, mobile homes, woodframed barns, ripped apart. It blew off of its foundation and is pretty much parked in the driveway. Reporter at least half a dozen twisters. Theres a car right there. You need to back up. Reporter hammered the state all evening. Hit another barn or another structure. Reporter across the country, at least 19 reported tornadoes, including touchdowns in nebraska and iowa. Dangerous, dangerous situation here. Reporter while some stormtested oklahomans didnt let hail stop their round of golf. Other seasoned weather watchers were amazed at what they saw. Look at the motion. Holy cow. Wow. This is an ef4 tornado. No doubt about it. Ripping the town apart. Reporter today, it is the small things in wynnewood that loom large. Anniversary card. But were okay. Reporter lisa buckner survived by racing to her emergency underground shelter. It was scary. Very scary. Especially by yourself. Reporter her home is shredded, but her will is not. Never in my life. I dont want to do it ever again. It was horrifying. Reporter drier weather is expected today and thats expected to help the cleanup effort. But here theyre bracing for another potential round of Severe Weather tomorrow. Savannah and natalie, it is, after all, the height of tornado season here. Terrifying images. Gabe gutierrez, thank you. We have a new look this morning at the likely matchup between donald trump and Hillary Clinton in the general election. This as trump prepares to meet with Republican Leadership on thursday. Well begin our coverage with nbc National Correspondent peter alexander. Good morning. Good morning. Ahead of the pivotal meetings in washington, donald trump faces a real challenge, trying to unite this fractured republican party. Paul ryans latest comments about trump may leave both men at least a little wiggle room over the partys convention, if they still dont see eye to eye. Hillary clinton. Donald trump. Reporter the fall fight coming into focus. Donald trump trailing Hillary Clinton nationally by five points, according to the latest nbc surveymonkey online poll. Paul ryan is deferring to his partys presumptive nominee, saying hed step aside as chair of the Gop Convention if trump asks. Hes the nominee. Ill do whatever he wants with respect to the convention. Reporter ryan with a reality check ahead of his thursday meeting with trump. If we pretend we are unified without actually unifying, well go into the fall election at half strength. That means well be less likely to win. Reporter what does ryan want . I want to get to know him and understand him better because i really dont know him. Reporter also on trumps docket, visits with leading republicans, whose sources tell nbc news want to discuss trumps tone. As voters head to the polls today in nebraska and West Virginia im ivanka trump, and i want to remind you to vote for my father, donald trump. Reporter hes already shaping a possible Trump Administration tapping Chris Christie to head up his transition team. The new jersey governor is promising to best serve the president elect and the nation. A policy adviser says itll be challenging for trump to attract top talent. Marco rubio is stamping out speculation that he would serve as trumps running mate again saying he does not want to be considered as trumps running mate, reiterating his concerns with trumps policies remain unchanged. Also this morning, ben carson, now one of Donald Trumps allies, requested a session with speaker ryan to take place ahead of trumps visit this week. The goal, to help warm the room for the trump ryan meeting. Interesting. To be a fly on the wall. Peter, thank you. While trump gears up for thursdays meeting, hes stepping up attacks on Hillary Clinton. But so far, shes not taking his bait. Andrea mitchell is covering the Clinton Campaign this morning. Good morning. Morning, savannah. Donald trump, surprising observers in both Political Parties by launching deeply personal attacks on hillary and bill clinton. The opening round of what is likely to be a vicious campaign. Hillary clinton courting independent women in a suburban area focussing on issues like equal pay. I raise it all the time and, you know, im accused of playing the gender card and all of that. The fact is, it is a real problem. Reporter after Donald Trumps toughest attacks yet, repeatedly raising bill clintons sex scandals from the 1990s. Calling her an enabler. She was a total enabler. Shed go after the women and destroy their lives. She was an unbelievably nasty, mean enabler. What she did to a lot of those women is disgraceful. Reporter trump getting even more personal about the man who was once his golf buddy and wedding guest. Hillary clintons husband abused women more than any man that we know of in the history of politics, right . Reporter clinton responding monday. Donald trump has really gone after your husband, and even you as an enabler, for the scandals of the 1990s. Im going to let him run his campaign however he chooses. Reporter what is trumps evidence . No doubt she did help rescue her husbands First White House campaign after jennifer flowers accusations of an affair. Im not a little woman sitting here next to my man like tammy winet. I love him and i respect him. Reporter days after the accusations that president clinton lied about an affair under oath first made headlines, Hillary Clinton gave this now famous response about the incident to matt on today. The great story here for anybody willing to find it and write about it and explain it is this vast, rightwing conspiracy that has been conspiring against my husband since the day he announced for president. Reporter more recently. Monica lewinsky said clinton had an impulse to blame the woman. Are his claims accurate . If not, do you feel a need to correct the record . I have nothing to say about him and how he runs his campaign. Reporter women a critical voting bloc, women heavily favoring clinton over trump. It remains to be seen whether voters in 2016 will care about the scandal decades ago, or perhaps blame trump for resurrecting them. Thank you so much. We should mention, thursday on today, well get former Vice President dan quayles take when he joins us for an exclusive, live interview. Interesting to hear from him after so long. We have breaking news overnight. A deadly stabbing attack at a train station just outside of munich, germany. Nbcs keir simmons is following that story for us. What can you tell us . Good morning, natalie. Europe has been on edge since the attacks in paris and brussels. Security services on alert. Now they have an assailant who shouted god is great as he stabbed passengers, according to witnesses. The attack leaving bloody footprints on the station platform. A 56yearold man killed inside the train car and another injured inside the train car. Discarded, a cell phone and pen. These were commuters on board the first train of the day. Two more men were knifed outside the station. The attacker is arrested. A 27yearold german national. Reports say he had a fourinch knife. The munich Prosecutor Says it is too soon to know whether the attack was motivated by islamic extremism. Train personnel are being praised for being courageous and stepping in and preventing further attacks. Keir simmons, thank you. We are getting our first look this morning at the canadian city ravaged by a massive wildfire. The flames moved far enough away from ft. Mcmurray to give them a chance to see the area. 80 of homes in one neighborhood burned to the ground, and the wreckage of blackened and melted cars remains on the road. Fire Officials Say almost 90 of the buildings in ft. Mcmurray survived. Justin trudeau vowed a multiyear commitment to rebuild the city. Now to the troubling accusation leveled against facebook. A former worker is claiming it censored politically sensitive content from its popular trending news side bar. This morning, facebook a scrambling to respond to accusations of political bias. After a report released monday by the website gizmodo, that says a team of facebook employees had intentionally suppressed news articles from conservative news sources. These news curators coming forward to say they were also instructed to artificially inject certain stories into the trending news module. In interviews, the curators describing grueling work conditions and humiliating treatment. According to a former journalist who worked on the project, workers prevented stories about mitt romney, rand paul and other conservative topics from appearing in the trending section, even though they were organically trending among the sites users. Facebook boasts hundreds of millions of monthly active users. This story itself a trending topic all night long. During facebooks april keynote address, Mark Zuckerberg touched on politics. We stand for connecting every person. For a global community. For bringing people together. Reporter in response to the allegations, a spokesman for Facebook Says it follows rigorous guidelines to ensure consistency and neutrality, and it works to be inclusive of all perspectives. We take allegations of bias very seriously. Facebook is a platform for people and perspectives from across the political spectrum. The Republican National committee released a statement on its website saying, in part, it is beyond disturbing to learn that this power is being used to silence viewpoints and stories that dont fit someone elses agenda. And other former curators they interviewed denied consciously suppressing conservative news. The outlet says it was unable to determine if leftwing news topics or others were suppressed. A lot of people will see if there is truth to it. Already trending on facebook. Also one of the nations top Traffic Safety organizations is issuing an urgent warning about a growing danger on the roads. Driving while high. Aaa says in some states that legalized marijuana, fatal accidents involving drivers who consumed pot are on the rise. Nbcs tom costello is in washington, d. C. , where pot has been legalized. Tom, good morning. Good morning. 13 more states considering whether to legalize marijuana. Washington state was among the very first, and now aaa Research Suggests that people high on pot there were seen let me start that again. People are seeing a double in percentage in the number of people high on pot who then were involved in fatal accidents. Driving under the influence isnt just about drinking and driving. So you smoked 30 minute ago, and youre saying that im not going to find any weed in this car . Reporter it can also mean driving while high. Why are you driving around smoking . You know its not a good idea, right . Reporter Legal Marijuana is spreading across the country. 20 states allow medicinal use. Four states, plus d. C. , allow recreational pot. It is a growing danger on the nations roads. Driving is already a tough task. When you add a drug that impairs our ability to manage that task, its a recipe for disaster. You are impaired. You are impaired. I have seen impairment. I have seen what impairment does. Reporter its been two and a half years since mary gaston waved goodbye to her 23yearold son blake at a suburban seattle restaurant. Seconds later at this interaction, he was hit by a car. The 33yearold driver now in prison admitted he was high on pot. Blake died right in front of his mom. It was a very traumatic death. It was very it was a very horrific death. Reporter Washington State legalized marijuana in 2012. This morning, aaa reports the percentage of drivers who had smoked pot and were then involved in fatal crashes in Washington State more than doubled between 2013 and 2014 from 40 to 85. With his trademark smile, blake gaston was a brother, son, musician, student, computer wiz and so much more. Even at 23 years, he had lived a hell of a life that was way, way too short, but hed lived a hell of a life. Some states set legal limits of exactly how much thc, the marijuana chemical, can be in your blood for you to be considered legally impaired. The new aaa Research Suggests those are meaningless. It doesnt accurately reflect real impairment. They think its better for police to be able to be empowered to determine whether somebody is impaired. Back to you. Tom costello, thanks so much. Lets go back to al, who is in new mexico with the forecast. Thats right. A little brisk right now. Yes, it is. But it is going to warm up a little later. Lets show you whats going on. Unfortunately, Severe Weather is going to start heating up again. You can see, weve already got strong storms firing up from chicago all the way down to tupelo, mississippi. Part of that same system that caused all the tornadoes yesterday. Today, we are looking from st. Louis, memphis, charleston, and could be an enhanced area that gets put in later on by the National Weather service. 14 million folks at risk for severe storms, damaging winds, hail, tornadoes possible. Tomorrow fires up again. Were going to be watching this very closely, as we get into the afternoon and evening hours. This will start moving toward the northeast and the midatlantic states. It will weaken as it gets closer to the coast. Were going to get to your local forecast coming up in the next 30 seconds. In the next 30 seconds. Good morning. Im meteorologist kari hall. We have clouds all across the bay area as temperatures now in the mid to upper 50s. Expect a lot more sunshine. Clouds will clear out of here quickly. A high of 66 in San Francisco. In the east bay 70. Trivalley in the low 80s today. Upper 70s for the south bay in the peninsula as well as north bay. Our temperatures will continue to climb as we go into the next several days. Big temperature changes coming, not just here, but across the rest of the country. Well have that story coming up in the next half hour. Guys . Thank you. Coming up, a Surprising New report tied to the tragic Christmas Day fire that killed three young sisters and their grandparents. Why the man who initially took the blame is now pointing finger at the girls mother. Well have her exclusive response. Matt . Savannah, plus, the beauty that makes new mexicos white sands one of the worlds natural wonders. But first this is today on nbc. scal good day, mlady i am sircanalot, here to save you from another breakfast bore. Wake up those eggs with glorious spam see what spam can do. At spam. 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