York, this is nbc nightly news. Reporting tonight, lester holt. Good evening. They were the faithful, adults and children who had gathered for friday prayers only to be targeted for death on a massive scale in a pair of suicide bombings. As many as 137 people are dead and more than 350 injured tonight. Victims of the attack against two mosques in sanaa, the capital city of yemen. Its a place where the u. S. For years now has been actively hunting down al qaeda terrorists. But a recent government overthrow has changed an already volatile landscape. And tonight for the second time this week, it is isis claiming responsibility for a deadly terror attack that has rattled the region and beyond. Nbcs katy tur has the latest developments. Reporter the first bomb went off inside the mosque, the second at the gates as those left standing tried to escape. In the pandemonium, worshippers rushed the wounded away while others prayed over the dead. Moments later, two more explosions at another mosque. One bomber believed to have hidden his explosives in a fake cast on his leg. Coordinated suicide bombings during midday prayers, targeting followers of the Shiite Houthi Movement that seized power in the capital last month. This father lost his son. Many victims were young boys. Those boys accompany their fathers to the friday prayers. Its really a family thing. Reporter within hours, isis claimed responsibility, just as it did for wednesdays Museum Massacre in tunisia, which left 20 Foreign Tourists dead. But again it offered no proof, a fact underscored by the white house today. It does appear that these kinds of claims are often made for a perception that they have, that it benefits their propaganda. Reporter some experts say yemen, an al qaeda stronghold, may be the next iraq for isis. With isis trying to say, look at your strongest branch, its barely able to defend the sunnis in yemen. We are much more capable of doing that. Reporter yemen has been a key u. S. Ally in the war against terror. But the u. S. Was forced to evacuate its embassy last month, as yemen plunges further into chaos and potential collapse. Katy tur, nbc news, london. In this country as we head into the weekend, a lot of eyes on the weather. Its the first day of spring, but in the northeast you wouldnt know it from looking outside. A big snowstorm hitting right now. And another arctic cold front about to sweep through. Nbcs rehema ellis reports. Reporter its a case of, not again. First day of spring, is this what you were expecting . Absolutely not. Reporter heavy snow crippled the morning commute in maryland and in philadelphia. Snowcovered roads made for treacherous travel. Two people died after their car crashed on the Atlantic City expressway this afternoon. Today, from Newark Airport to washington dulles, the northeast saw more than 585 flights canceled, nearly 583 others delayed. In new yorks long island, the hope is this is the last time theyll have to sand and salt the roads. Another shot of cold air comes in over the weekend. Temperatures in the northeast will drop to 10 to 15 degrees below average. Reporter its not the first time weve had march storms. The superstorm of 1993 dropped more than three feet of snow from alabama to new york. Im really looking forward to spring. But this is really not the first day of spring id imagined. Reporter other big snowfalls on the first day of spring, washington, d. C. , 4. 2 inches in 1965. Philadelphia, 9. 6 inches in 1958. And boston got 10. 2 inches in 1944. It looks like winter. Reporter and now todays weather has many asking, is spring really here . Officials are warning travel on the roads remains dangerous tonight. And several states have speed restrictions in place. And tomorrow, instead of being out in a park like this for the first full day of spring, a lot of kids and their families may be housebound one more weekend. Lester . All right, rehema ellis. Now to a place that could use all this. Were talking about the west where drastic new rules are going into place to save water, in a region absolutely parched by drought. California lawmakers are working on a relief plan, but the state would need 11 trillion gallons of water to recover from this emergency. And now warmer months are, of course, on the horizon. Nbcs Miguel Almaguer is in piru, california, for us tonight. Miguel, good evening. Reporter lester, good evening. This is symbolic of californias drought. Lake piru just outside of los angeles is at 20 of capacity. All of the green you see around me should be covered 30 feet under water. Officials here say they havent seen water levels this low for this long in decades. This is the crisis crippling california, a drought so devastating nasas senior water scientist is sounding the alarm. If we dont take measures to conserve our surface water in our reservoirs, well have about a years worth of water left. So it will be gone. Reporter reservoirs are dangerously low because the snowpack that supplies a third of the states water is just 13 of average. This is yosemites half dome in 2011. And now the view today. Entering its fourth Consecutive Year of drought, the golden state is turning deep red. 40 of california is in exceptional drought, the most severe category. Governor brown told chuck todd today theres no greater crisis facing the state. It does take time. And we are running out of time because it is not raining. Reporter brown wants a billion dollars for Water Infrastructure and to help struggling communities, but many call the plan a bandaid. In the central valley, farmers are abandoning fields and jobs are drying up. This food bank alone helps 350,000 people. We get people come in from the county now that lives on the fringes and theyre they work in the fields. Reporter now statewide, lawn watering is limited while at restaurants you wont get a glass of water unless you ask for it. This is the new liquid gold, now harder to find and more valuable than ever. The outlook and the view in california isnt pretty. With dismal water levels on this nearly 90degree day, theres talk of water rationing. The governor says hell revisit that discussion in three weeks when the socalled rainy season officially comes to an end. Lester . Miguel, that view makes quite a statement there, thank you. Former secretary of state Hillary Clinton has been hit with a formal request to turn over her private email server to investigators. The request came in a letter from the head of republicanled Congressional Committee examining the attacks on u. S. Diplomatic posts in benghazi, libya, in 2012. Clinton has previously said the server is private and would stay that way. The letter gives clinton until april 3rd to respond. Now to a story getting a lot of attention today as much for what we dont know as what we do know. Its the mystery in mississippi involving an africanamerican man found dead in circumstances that for some are reminders of a painful era of the past. Now police and the fbi are methodically trying to determine whether something sinister is at work here. Nbcs Kerry Sanders has more. Reporter its a mystery that harkens back to an ugly past. A black man found hanging from a tree limb, a bedsheet used as a noose. 54yearold James Otis Byrd had been missing for two weeks when his body was discovered deep in the woods near port gibson, mississippi. Its just like all of a sudden, bam. We dont do stuff like this, not these days. If the evidence said that he was lynched, were going to seek that person out and try to find who they are and try to get a conviction on them. Reporter byrd had served time in prison for killing a woman during a robbery but was paroled in 2006. Law enforcement sources tell nbc news byrd had recent financial problems. He was last seen leaving a casino march 2nd and was reported missing days later. While investigators are leaning towards suicide, the fbi says its too early to say. Were really trying to paint a picture as to what was going on, both personally and professionally to help us further identify a potential reason. Reporter Officials Say among the clues that theyre working with, there were no signs of a struggle and byrds hands were not bound. Tonight, there are more than 30 state, local and federal agents involved in this investigation. An autopsy that was conducted today should produce some results as early as next week. Some Authorities Say those results may actually provide important answers. Lester . Kerry sanders tonight, thank you. There is encouraging news to report tonight in the fight against alzheimers. While there is no truly effective treatment, the results from a new study are so promising theyve caused something of a stir. A new drug being called a potential Silver Bullet to slow down memory loss. Our National Correspondent kate snow has details for us. Reporter after his mothers cognitive abilities started declining a few years ago, 30yearold max lugavere started looking for ways to improve his odds. I learned that changes in the brain dont begin the minute that you have symptoms. They begin decades prior. Reporter which is why experts are cautiously optimistic tonight about initial results from a new drug given to patients who seem to be in the early stages of alzheimers disease. They met and exceeded these high expectations. Reporter on wall street, the stock price for the maker of the new experimental treatment spiked. How encouraged are you by this . This is the first evidence that we can modify the progression of alzheimers. And i think thats very encouraging indeed. Reporter researchers tested the treatment on 166 people who had mild alzheimers or early signs of dementia. Some got a placebo, others got different doses of the drug. Those who received the highest dosage had the slowest buildup of brainclogging plaques linked to alzheimers. They also performed better on memory tests. For the first time, people with mild changes in memory but not frank alzheimers disease were included. They were able to maintain their thinking and continue to live independently. Reporter there were some side effects, headaches and brain swelling. And experts caution this was a small initial study. In order for us to really see if theres value, you have to do it much larger groups, like thousands of individuals. Reporter the drug does now move on to larger trials. But even if everything goes well and the drug is judged to be safe and effective, lester, it would be several years before it would be available. Kate, thank you. Since the late 90s, her name has been synonymous with scandal. Now Monica Lewinsky is continuing her emergence back into the public eye, with a plea that comes from her experience with infamy. Nbcs Peter Alexander has her story. Reporter this time Monica Lewinskys stepping into the spotlight on her terms. Anyone who is suffering from shame and public humiliation needs to know one thing you can survive it. Reporter lewinsky, for years the target of ugly attacks and worldwide ridicule, is now tackling the topic. Public humiliation as a blood sport has to stop, she said. During a ted talk thursday entitled the price of shame, the former white house intern opened up about her affair with president clinton 17 years ago. At the age of 22, i fell in love with my boss, she says. Two years later, lewinsky suffered devastating consequences. Who didnt make a mistake at 22, she asks. Her goal today, to stop cyber bullying. Part of what she calls a culture of humiliation. I was branded a tramp, tart, bimbo and of course, that woman. I did not have sexual relations with that woman. Reporter it was easy to forget that woman was dimensional and had a soul, she says. This is a reinvention for Monica Lewinsky. Shes reclaiming her story. Shes telling it in a way we havent heard before. Reporter now 41, lewinsky is calling for compassion over negativity. Empathy from one person can make a difference. These days she says shes turned the page. I know its hard. It may not be painless, quick or easy, but you can insist on a different ending to your story. Reporter focused on her future as she tries to give new purpose to her past. Peter alexander, nbc news, washington. Weve got a lot more still ahead, including this one. Do you believe in reincarnation . How one little boy shocked everyone with what he knows about another mans life long ago. Its a fascinating story. Also a lifechanging turn in the pool for american Missy Franklin, a breakout star at the london olympics. How all those medals are about to pay off big time. Were back now with a tale that you have to hear all the way to the very last twist. A young boy who says he remembers things he couldnt possibly from a time long before he was born. Thats according to his mom. She turned to experts of the mind for some answers. Nbcs Cynthia Mcfadden tonight with the incredible story of what they found. Reporter its not unusual for little boys to have vivid imaginations. But ryans stories were legendary. He said, mom, i have something i need to tell you. I think i used to be somebody else. And he started just telling me these stories about how he had lived in hollywood. His stories were so detailed. It just wasnt like a child that could have made it up. Reporter ryan talked about dancing on broadway, working for an agency, traveling the world, being married five times. He even said the street he lived on had the word rox in it. And it would be, my last room was grander. I want to go back to my swimming pool. Reporter but things got really strange when they picked up a book about the golden age of hollywood. She turns to a page. And i said, yeah, thats me. Thats who i was. Reporter thats me . Yeah. Reporter but the man in the picture wasnt even a major star, just an unnamed extra with no lines in an old mae west film. Thats when ryans mother turned to this man, dr. Jim tucker, a child psychiatrist at the university of virginia. For 50 years, the Prestigious School has collected more than 2,500 cases of children claiming past lives. And your conclusion after 50 years is what . These cases demand an explanation that we cant just write them off. Reporter hes return about them in his book return to life. Had you ever given much thought to this whole idea of reincarnation . No, maam. I grew up in a baptist church. Thats not something that we were taught to believe in. Reporter but with the help of a movie historian, the man ryan pointed to in the picture was finally identified. His name, marty martin. And just like ryan said, he was a former actorturnedhollywood agent who danced on broadway, was married five times and even lived on roxbury drive in beverly hills. In all, dr. Tucker confirmed that 55 of the things ryan said were true. Of course, a lot of people are going to say, come on, this is the parent or somebody else feeding them information. Its inconceivable that the parents for some reason had done all that. This information wasnt on the internet. Reporter but there was one fact that scientists thought ryan had wrong. He said he didnt see why god would let you get to be 61 and then make you come back as a baby. That looked like just an incorrect statement. Reporter thats because martins death certificate says he was 59 when he died. Since then, ive gotten information that the death certificate was actually incorrect, which would have made marty martin 61 when he died. Ryan was right all along. Reporter are you glad youve had this experience . Yes, i am. Reporter a chance he says to live his own wonderful life. Cynthia mcfadden, nbc news, tulsa, oklahoma. One to ponder, isnt it . Were back in a moment with the cheating scandal that has parents climbing the walls, quite literally. In india more than 600 students have been expelled from school over an epidemic of cheating, and you cant blame it all on the kids. Some parents scaled the walls at this school to reportedly pass cheat sheets to their children inside. Students were taking their tenth grade finals, which play a big role in who gets into indias best universities. Congressman aaron schock is resigning amid questions about his expenses and now hes the center of a federal investigation. The feds are looking into how the Illinois Republican used taxpayer money in his personal investments. Schock, who had a fondness for chartered planes and downton abbeythemed office decor, wont officially leave office until march 31st. A spectacular show in the skies over norway today as the moon completely blocked out the sun, a total eclipse. Tens of thousands gathered to watch it. A clear view on two remote islands. The next one will be visible over indonesia in 2016. When we come back, a young olympian who passed up a lot of zeros to swim at college, now looking at a future filled with gold. Test test test test test test test test test test test test test test test test test test test test test test parra when we first met Missy Franklin back in 2012, she was still in high school and winning gold medals at the london olympics. She could have turned pro back then and taken all the money that would have come with it. But missy had much bigger goals than simply landing a payday. Chris jansing who covered franklin during the olympics caught up with her before her new plunge. Reporter say this about Missy Franklin, the girl loves to dance, as a workout or as a final warmup before a race with her uc berkeley teammates. Now the olympic champion who said no to huge endorsement deals after the london olympics is about to take her final lap before leaving her team to turn pro. Youre going to cry. I know. Its a huge transition. I have made the most incredible friends here. Its going to be a world record for Missy Franklin. Reporter a breakout star in london, missy won five medals with her parents, dick and d. A. , beaming from the stands. You see the American Flag go up, what parent wouldnt be bursting with joy . And seeing her cry. Reporter how does it feel to be famous . I still dont feel famous. Reporter come on. I still dont. Reporter and yet its not every girl who gets to celebrate her birthday with prince harry. Still, she gets even more satisfaction cheering up kids at a colorado hospital. Shes like the pied piper with kids. She loves them and they love her. Reporter an only child, the franklins have always been extremely close and moving away has been hard. So mom had an idea. Why dont i move to berkeley and ill find us a duplex . I did nix the duplex idea. The duplex might have been a little much. I love them. I love them so much. Its been horrible for all of us being away from each other. Reporter a College Sophomore and psychology major, the franklins little girl is growing up. That goofy kid they couldnt stop from dancing, couldnt keep out of the water, now wants to become the most decorated female olympic swimmer in history. Im doing this because i love it. If i get there, thats great. If i dont, i tried as hard as i could and i had a blast while i was doing it. Reporter and what a blast shell be to watch. Chris jansing, nbc news, berkeley, california. That is going to do it for us on this friday night. Were glad youre here. Im lester holt. For all of us at nbc news, thank you for watching. And have a good weekend. Good night. This evening the giants continue their preparation for the Upcoming Season in the Sonoran Desert a place they have trained for six decades. When sepeda mccovey and they continue their training in the desert in the Cactus League coming up next. The weather here in the desert is fabulous as we fly over the top of