on the broadcast tonight, fever pitch. the extreme heat moves east. temperatures hovering around 100. how much worse can this system get? dire warnings tonight about what is happening half a world away where millions of people are starving to death. what downturn? it seems like all we hear about, stories about jobs being cut, but not in a place tom brokaw will tell us about tonight. and touchdown, the final mission for america's shuttle program comes to an end, and we're all watching the end of an era. "nightly news" begins now. captions paid for by nbc-universal television good evening.

here's just one way of looking at how cruel and how relentless this oppressive heat wave has been so far. over 3,000 separate records have been set in different places for the highest overnight temperature. extremely hot daytime temperatures in july are one thing, but it gets dangerous when no one can catch a break, like in chicago at 3:00 a.m. when it's 90 degrees outside as it was overnight. government forecasters have issued heat warnings for some extensive stretches of our country. this dome of hot air has pushed temperatures very high, and then there's that heat index, what the heat actually feels like when you're out in it. nbc's anne thompson is out in it in fact tonight in hot times square here in new york to start off our coverage. hey, anne, good evening. >> reporter: good evening, brian. more than 148 million americans are under a heat advisory or warning tonight. this is not just an inconvenience. this is deadly. the heat wave already claiming

more than 20 lives, and here in new york city the hottest days are ahead. the eastern seaboard is a griddle. the temperature reached the mid-90s, but the humidity made it feel well over 100 degrees. >> we feel nasty, which is sweaty and nasty. >> reporter: up and down the northeast corridor, officials urge people to conserve energy, limiting their physical activity and electricity usage. >> extreme heat is a real danger. it takes a toll on people's health, and it can put a strain on our infrastructure. >> reporter: a problem here and in the midwest. >> i'm kevin tibbles in chicago on a sizzling day five with no relief in sight. with the heat index, it's 110 degrees. some 7,000 homes and businesses are without power because of the heat, sweating it out without ac, and today ac is golden. >> reporter: the nation's largest independent grid operator, pjm, manages electricity across some 13 states in the midwest and mid-atlantic.

today demand climbed to 158,000 megawatts an hour, approaching a new record. with air conditioners blasting, come worries of a repeat of the 2003 blackout. in new york city, utility officials tried to calm fears. >> we could handle five days in a row of -- of 100 degrees. >> reporter: one of the nation's most miserable spots, washington, d.c., says the weather channel's chris warren. >> when the sun goes down, not much help. still around 90 degrees at midnight expected tonight, and for morning lows, starting the day in the mid-80s. >> reporter: for those who had to work outside caution was key. coaches at the practice for maine's all-star high school football game put in a special game plan. >> we have a ten-five rule installed today. we work for ten minutes and take five minutes for water and the shade. >> reporter: air quality alerts followed the soaring temperatures. almost 60 areas in the eastern half of the country warned. from maine's acadia national park, west to chicago, to raleigh-durham in the south. >> our bigger concern is that

it's going to last several days and that may put us us at increased risks over the next couple of days. >> reporter: and adding to the misery, a warning tonight for swimmers and kayakers here in new york city to stay out of the water because of a raw sewage spill in the hudson river. brian? >> talk about insult to injury. anne thompson in times square tonight to start us off. anne, thanks for that, i think. we're trying to keep a watch for you on when this wave will break where you live, and joining us again tonight, our friend janice huff, chief meteorologist wnbc here in new york, and i know you have to answer regionally, and no two places will have the same experience. >> exactly. there will be a break for the northeast which is experiencing the heat wave now. the 103 degrees in newark, new jersey, that set a record. there were parts of iowa yesterday that had a heat index above 120 of what it felt like. those areas of the country won't get the relief from the jet stream that the northeast will coming up later in the weekend and into next week. >> so relief first, maybe northeast?

>> northeast first, starting in the weekend, but tomorrow it's still going to be hot. so here's the forecast. we'll look at friday first and show you what's going to happen. still more heat, record-breaking heat. the jet stream is still too far to the north. we're expecting 101 in new york city tomorrow. temperatures record-breaking, maybe down to washington, d.c., but by sunday it does shift a bit. it drops south. that means cooler air will come in or at least not as hot and into the 80s in new york city by sunday into monday, but notice the southeast, the southern and central plains, still in the brink of that heat. they will not get the relief from the jet stream. patterns over the oceans in the north atlantic oscillate back and forth. it's in a negative phase right now which may be attributing to the heat and the drought over parts of the southern plains and why that's continuing and why they won't get any relief because the jet stream is just not strong enough to go that far south. >> see if you can do something for those folks in st. louis. >> i really wish i could. >> janice huff, thanks for joining us here in our studios as always. overseas, tonight we'll tell you about the next global crisis you will be hearing about.

it's bad and fair warning, it's hard to watch, and it's going to get worse. the u.n. is using a word we don't hear them use often, and that's famine. it's happening in the horn of africa triggered by years of drought and poverty and civil war in some cases and setting off a human tide of refugees. the drought is severe. the humanitarian crisis is centered in somalia but also kenya, ethiopia and djibouti, devastating crops and livestock and sources of drinking water. the u.n. estimates more than 11 million people are in urgent need of food assistance, including millions of children. we have a report tonight from the kenya-somalia border, and a reminder, again, these are some tough images. >> reporter: famine has returned to africa. in this village it hasn't rained heavily for two years so children are starving, desperately in need of help. >> they really need it

immediately. it's a matter of urgency, and some of them they cannot even wait. >> reporter: millions of people have been forced to flee their homes. 400,000 have come to this refugee camp in eastern kenya, most from somalia, and every day 1,500 more arrive, escaping war as well as famine. to get here abby has walked for almost a month with her five children. along her way, she was joined by other families crossing the border, too. this woman left home with her 12-year-old boy, mother and son together, but he collapsed from hunger and died on the way. for so many people this will be the first real meal that they have eaten for several days. the rations are small, the camp is overcrowded, and yet many people are so happy to be here.

but even here there is a chronic shortage of food as the aid agencies struggle to cope with demand. across the border in somalia, the situation is more desperate and much more dangerous. the militant group al shabab, affiliated to al qaeda, controls parts of the country. only now is it letting some aid through. all the while across parts of east africa, the conditions are worsening and the famine is spreading. nbc news on the kenya-somalia border. >> what's sadly common about this is that it's been going on for some time, but the world is just taking note, and before long there will be camera crews and journalists there. we'll continue to cover this story in the coming days, and we know a lot of our generous viewers will want to help the people in the horn of africa. there is a list of charities who are doing just that on our website tonight, that's nightly.msnbc.com.

in washington tonight, the clock keeps ticking away towards the treasury department deadline on the debt ceiling, and as far as progress towards a solution is concerned, the situation remains, as they say, fluid. next's kelly o'donnell watching it all with us tonight. kelly, good evening. >> reporter: hi there, brian. well, there was a hurry up and get here phone call from the white house to democratic leaders here in congress late today with less than an hour's notice to meet with the president. now this came after a day of anxiety and griping with democrats worried that the president might be about to strike a deal with speaker boehner that they wouldn't like in order to try to bring along those hard-to-wrangle house republicans. the president's budget director was here, and he got an earful about that from senate democrats, and it was made worse after whispers and news leaks that a bigger deal for debt reduction was close, and then all sides publicly denied it. >> i always believe that keeping the lines of communication open were important, and frankly i

think it would be irresponsible on behalf of the congress and the president not to be looking at backup strategies for how to solve this problem. >> there is no deal. we are not close to a deal. we are -- obviously the president is in discussions with all the leaders of congress. >> reporter: and more talking is going on, and brian, we are hearing complaints from democrats and republicans, even veteran members of congress, that they don't like that the negotiations are happening in secret. they don't know the details, and there's so little time left before that deadline for preventing default. brian? >> august 2nd it is. kelly o'donnell on the hill for us tonight. kelly, thanks. there's another standoff tonight between the national football league team owners and the players. both sides trying to avoid a season-killing strike. as you may know, a whole lot of fans and a lot of cities are waiting for a resolution here. darren rovell covers the business of sports for cnbc. he's with us from atlanta where

the owners are meeting, and darren, what can you tell us? >> reporter: good evening, brian. for 132 days the owners locked out the players in the nfl, but at 7:00 eastern time today in atlanta the owners voted 31-0 to ratify the new collective bargaining agreement. that brings it back to the players who in washington, d.c. will have a conference call to vote whether they will now drop the antitrust litigation and then recertify so that they can have a settlement, and they could then vote on a new collective bargaining agreement. a lot of money on the line if they don't get it done in the next 48 hours. they will lose at least one preseason game, and then if they don't get it done in the next week, it would be $200 million on the line for eareseason week lost, but it looks pretty good as one side, the owners, have ratified a new collective bargaining agreement. now they will throw it back to the players to s see if we'll he a season.

brian? >> darren rovell in atlanta. thanks for the update. we'll stay on it. and when we come back here tonight, one place in this country where business is booming, but why some are a little bit worried it's an echo of another bubble we all came to know and love. and later, coming in for one last landing as nasa says an over and out finally to the space shuttle program.

this recession, then you know we've brought you so many

stories about people losing jobs, losing homes. tonight we have a story about one place in america where both happen to be booming, where according to a new study employers expect to expand their work forces by 15% over the next few years. tonight tom brokaw reports from california's silicon valley. >> reporter: silicon valley, the mother load of the high-tech business, has another gold strike under way. some of the hottest new names and video games and online services are expected to go public for astronomical prices, and that means a lot of suddenly wealthy people are in the market for a new car with a pricey name, or a new home. there's no housing crisis in the silicon valley. >> you're having homes sell over list price but not only over sometimes several hundred thousand over. >> reporter: who are these people getting rich or hoping to in the middle of a great recession? >> record-breaking month.

>> reporter: 25-year-old dylan smith and his 26-year-old boyhood friend aaron levy are two of them. >> introducing box.net. >> reporter: in 2005 they opened a company called box which allows companies to share and store files from cell phones, ipads and androids. in the last nine months, dylan and aaron almost doubled their work force. they are now up to 6 million users, and they are moving to a new building three times as large. >> we wanted to be right in the center of silicon valley where there is much more talent and much more capital, much more access to resources, and i think this is the place to do that. >> reporter: they expect to more than triple their revenue every year for the foreseeable future. >> the biggest temptation is probably to try to do too much, although we are growing very quickly. we really need to focus on what's going to drive the most value for the business. >> reporter: it does seem that every corner in the silicon valley has an office park fully occupied by hot, high-tech companies. of course, it was that way back in the 1990s, and then the bubble burst. could that happen again? tim draper is a leading valley

financier. it could happen again, he says, but this time conditions are different. the whole world now is the marketplace. >> you can start a business anywhere, and it will spread around the world fairly quickly because we now have 3 billion users of cell phones and 2 billion users on the internet. >> thank you very much. >> reporter: dylan and aaron aren't thinking of going broke. they are having too much fun growing their company. they must be doing something right. big-money experts say they could get $600 million for box right now, but it's not for sale. >> yeah. >> reporter: tom brokaw, nbc news, silicon valley. one other economic note tonight. it's a done deal. the united states government no longer owns a piece of the chrysler corporation, but the majority stakeholder is now the italian automaker fiat. american taxpayers, along with fiat, helped bail chrysler out a few years back.

fiat has gradually been raising its stake, and today it bought the last of the u.s. shares along with a small stake held by canada, so tonight fiat owns 53% of this once proud and formerly all-american brand, and at the end of the day the u.s. treasury estimates american taxpayers lost $1.3 billion on this deal. up next here tonight, is it possible while one era ends another one is about to begin?

more material today, some audio the nixon library released more material today, some audio of the president, but mostly a trove of memos, many written by folks who are still around and still in the public eye, and they show people during a markedly different era, many of them fierce in their defense of the president. >> buhler. >> before ben stein was a deadpan actor and tv personality, he was a nixon white house aide. now you get to read his idea that the white house should commission a country western song about a woman whose p.o.w. husband is home from vietnam in time for christmas. ben also suggests john wayne could give a speech comparing his movies to nixon's presidency, lynch mobs out to get an innocent man, and he says clint eastwood should speak up for nixon. we hear nixon himself select pat buchanan, among others, for a special group with a special task.

>> for the purpose not of cheering but solely of attacking and defending is of the highest priority. >> later in another memo david gergen sends along three possible short options for nixon's resignation letter. in another gergen says the president should say he's leaving with a heavy heart but without bitterness and ask the public to rally behind gerald ford, which he did. speaking of ford, there's a snarky letter from him complaining of being blacklisted by nixon who brought him on as vice president just over a week later. no hard feelings apparently. the memo showed diane sawyer, then a 25-year-old nixon white house aide, got in trouble for telling a family friend he was being nominated as a federal judge. problem is a u.s. senator was supposed to tell him first. sawyer apologized profusely. in 1969 george h.w. bush, then 45 years old, writes to a white house aide. when i grow up, i want to be president, i think.

and then you can even see the end coming for the entire outfit, when david gergen writes ominously that he received an urgent call from reporter bob woodward that "the post" was agonizing over a story that would implicate richard nixon in a cover-up. richard nixon was gone 469 days later. we have placed all of these documents and the new recordings on our website, nightly.msnbc.com. they make for some fascinating reading and listening. and when we come back here tonight, the space shuttle program rolls into the history books, but what next?

a major chapter in america's space program came to a close early this morning as the space shuttle "atlantis" touched down for the last time. this means for american astronauts, for now the russians are now our ride into space. as you might imagine, this was a bittersweet day for the men and women who have made it all happen. nbc's tom costello reports tonight from the nbc space center. >> reporter: in a pre-dawn

landing with nasa precision, "atlantis" and her crew of four returned home safely this morning. >> main gear touchdown. >> reporter: at 5:57 a.m. america officially retired its last space shuttle. >> mission complete, houston. after serving the world for over 30 years, the space shuttle has earned its place in history, and it's come to a final stop. >> reporter: inside mission control and outside in houston where 4,000 employees and their families had gathered, they celebrated the end of an era. >> you get goose bumps. you want to cry, but you want to be happy at the same time. it's just awesome. >> reporter: back in florida, with sunrise breaking behind "atlantis," a tearful tribute to the hundreds of thousands of people who have worked on the program since the beginning. >> i personally want to salute them and everybody who has been involved in this program. it's been a 30-year journey that has been absolutely incredible. >> reporter: so after 30 years,

135 missions, 541 million miles traveled, the nation's space shuttles are all coming to a complete stop at museums across the country as tourist attractions. today, one last chance for a souvenir photo. >> you know, i was just thinking about all the people that i have worked with out here. >> just a shame it has to come to an end. we don't know where our future is right now. >> liftoff. >> reporter: the future is hazy. commercial space flights within five years, even longer for deep space missions. >> and hopefully i want that picture of a young 6-year-old boy looking up at a space shuttle in a museum and say, you know, daddy, i want to do something like that when i grow up. >> reporter: a dream that it countdown clock picks up again. tom costello, nbc news, cape canaveral. >> and that's our broadcast for this thursday night. thank you for being here with us. i'm brian williams. as always, we hope to see you right back here tomorrow evening. good night.

-- captions by vitac -- www.vitac.com we begin with breaking news tonight. good evening. i'm jessica aguirre. >> and i'm raj mathai. a 60-acre grass fire in morgan hill burning in the area east of 101. if you're familiar with the area, it's up the hill from the target store right. >> at 101 and cochran. it's threatening several homes as you can see how close they are to the homes, the smoke. the morgan hil