scorching temperatures set to last for days. amid the heat, in massachusetts, 911 services knocked out statewide for hours. and in the west, dozens of wildfires burning. a state of emergency in new mexico. evacuate. foedo and the warning in texas. the first potential tropical storm of the ar taking aim. al roker is tracking it all also tonight, president biden's new executive action shielding 500,000 undocumented spouses of u.s. citizens from deportation. who will qualify? and republicans attacking the pl a nesty. boeing's ceo on capitol hill, testifying for the first time since that door plug blowout. the dramatic moment in the room. his apology to mi omax ash victims, and the grilling he ced after yet another boeing whistle-blower comes forward. justin timberle arrested in the hamptons for dwi. the mug shot just out. what he allegedly told the officer about how much he had to drink. and the celebration is on in boston. the celtics bringing home their record 18th nba championship. >> announcer: this is "nbc nightly news" with lester holt. >> good evening and welcome. tonight, millions more are under heat alerts as the blanket of brutally hot air we've been watching settles into the northeast, now stretching from iowa to maine, with temperatures into the 90s. fast forwarding us right into what feels like the middle of august. 50 to 75 record highs could be broken this weekend. cities, including chicago, washington, d.c., and philadelphia expect to see at least five days at 90 degrees or higher. many cities in the hot box are urgently warning residents of health dangers, especially with the hottest temperatures still to come. the heat itself just part of the weather story we're watching tonight. in the west, wildfires are on the rampage, while the texas coast is facing a tropical storm threat. al roker has the latest forecast. but let's start with maggie vespa. >> reporter: tonight the extreme heat is expanding east. >> it's hot! really, really hot. >> reporter: with 73 million americans from iowa through maine sweltering in record-shattering temps. detroit, cincinnati and new york all hong in the 90s for at least five days. >> every region of upstate is going to be hit with over 100 degrees. >> reporter: officials in massachusetts giving out local numbers for first responders after the state's 911 system went down for hours today. >> we thought it was important, particularly with the heat. >> reporter: the heat index already at 100 degrees in chicago and d.c. 105 in pittsburgh, where severe storms overnight knocked out power for tens of thousands. families desperate for relief. >> it feels like it's harder to breathe. >> when i step outside, it's like i'm in an oven or something. >> reporter: like you're in an oven? >> reporter: out west, the heat is fueling more than 20 wildfires. thousands evacuated from redoso, new mexico after two fast-moving wildfires merged nearby. meanwhile, in texas, increasing swells crashing on to the coast, the potential tropical cyclone swirling in the warm gulf waters. the heat costing more than ever. a new study out this month warning air conditioning costs this summer will hit a ten-year high $719 as americans try to keep homes cool amid severe prolonged heatwaves. pittsburgh dad shawn malloy says his electric bills soar $150 in the summer. >> whenever the heat goes, it's skyrocketing. >> reporter: is it tough on the budget? >> yes, it is. >> reporter: researchers call it the cost of climate change as dangerous heatwaves become more common. >> and maggie vespa joining us now from pittsburgh. maggie, this intense heat is now closing some schools here along the east coast. >> lester, that's right. districts from boston and buffalo have announced they're switching to half days to send kids home before temperatures peak. and one district in massachusetts ended the school year early, starting summer break today. lester? >> all right, maggie, thanks. let's bring in al roker. al, this is just the start of the heat and an active tropical former storm system. >> absolutely, lester. we have a lot going on. 73 million people from iowa, new england, the appalachians. heat watches or advisories. for tomorrow, records possible in syracuse, bangor, elkins and the wilmington, and the next few days temperatures stay in the 90s, air temperatures from concord to cincinnati to chicago and those feels-like temperatures will be even higher. 9 million people at risk from duluth down to garden city. thunderstorm watches and tornado watches up into minnesota, and we've got tropical storm warnings now from brownsville just to the south of houston. what we're looking at, heavy rain due to that storm, which could become alberto, anywhere from 7 to 10 inches from brownsville to bay city. lester? >> all right, al, thank you. let's turn now to the major immigration announcement by president biden, shielding hundreds of thousands of undocumented people who were married to u.s. citizens from deportation. well, former president trump is slamming it as an election year amnesty. here is julia ainsley. >> reporter: tonight, president biden announcing a sweeping new executive action, preventing the deportation of an estimated half a million migrants who are married to u.s. citizens. >> these couples have been raising families, sending their kids to church and school, paying taxes. >> reporter: the new move applies to migrants who crossed the border illegally and have been here at least ten years. they'll now get a pass to citizenship. previously, migrants who crossed the border illegally would have to leave the country to apply for citizenship through marriage, and some were denied reentry, a risk javier castro wasn't willing to take. >> i have a wife. i ve two ks. i have a home. this is not something that i want to roll the dice at all with. >> reporter: qiros castro is a nurse in houston, where he lives with his high school sweetheart haley, their 5-year-old daughter and 2-year-old son. the white house says he'll likely benefit from the president's move. what do you and your wifel your children about yr immigration status and your journey? >> my daughter doesn't fully understand. she has no idea what's at stake. i guess the stress, the certainty. >> reporter: there have been a record nearly ten million illegal border crossings since president biden took office. former trump calling today's move an unconstitutional mass amnesty that will encourage more people to come here illegally. >> our country is under invasion. we should not be talking amnesty. we should be talking about stopping the invasion instead. >> reporter: and it followed the president's executive action, tightening asylum restrictions. since then, the number of illegal border crossings has dropped from 4,000 a day to just over 2100 a day, according to dhs officials. though smugglers are boasting nothing at the border has changed. this smuggler advertising on whatsapp his menu of available routes for migrants to cross illegally into the u.s. the white house says the new protections will start by the end of the summer, but the new policy may face legal challenges. lester? >> julia ainsley, thank you. the ceo of boeing faced tough questions on capitol hill today six months after that door plug failure on max 9 jet. but now a new boeing whistle-blower says the company may have used substandard parts. here is tom costello. >> shame, shame! >> reporter: met by chants of "shame" as he entered the hearing room, boeing's ceo david calhoun quickly apologized to the families of those who died in two max 8 crashes overseas. >> i apologize. for the grief we have caused. >> reporter: and promised boeing is change. >> our culture is far from perfect, but we are taking action, and we are making progress. >> reporter: but calhoun came under immediate bipartisan fire. >> this hearing is a moment of reckoning. >> reporter: for the max 8 crashes, the max 9 door plug blowout in january, quality control breakdowns, defective parts, and clear reports of falsified documents, intimidation and retaliation. >> it appears that boeing has fostered a culture that censors people who try to speak up and help. >> you're the problem. and i just hope to god that you don't destroy this company before it can be saved. >> reporter: today a new whistle-blower claims boeing 737 max's assembly line lost hundreds of parts that did not meet boeing specs, which he claims were hidden from faa inspectors and may have ended up in planes, and that it could lead to a catastrophic event. >> i have not directly spoken to any of the whistle-blowers. >> you think that would be a good idea to do that? >> yeah, i think it would. >> how could you? >> reporter: many family members remain furious at a previous justice department agreemlowing boeing and its execs to avoid criminal prosecution after the fatal crashes. but justice now says boeing has violated that agreement. nadia milleron lost her daughter samya stumo. >> he is responsible for 346 deaths, and he is free. and he has no criminal charges against him. >> reporter: zaporia curry lost her father. >> i've never seen worst acting in my life than david calhoun's apology. >> reporter: and the justice department could still charge boeing and the ceo? >> prosecutors have until july 7th to decide. but boeing is critical to if national economy, space program, national defense. so the government has a lot to weigh in deciding whether to file charges. lester? >> all right, tom costello, thank you. tonight russian president putin making a rare visit to north korea, a crucial supplier of arms for russia's war in ukraine, while the u.s. is expanding its capability to arm the ukrainian side. courtney kube reports on this new arms race. >> reporter: russian president vladimir putin just arriving in north korea, only his second trip to the isolated nation in more than two decades. hugging north korean leader kim jong-un. another sign of a deepening partnership between the men, with kim looking for assistance with military technology while putin is getting a major boost for his war in ukraine. north korea has sent millions of rounds of ammunition, artillery shells, and missiles to russia, according to u.s. officials. but ukraine now getting more help from the u.s. from this new factory in texas. here the u.s. military produces artillery shells known as 155 rounds, the kind they are sending to ukraine. at the beginning of the war, the u.s. made about 14,000 rounds per month. now they're at 30,000 and expect to hit 55,000 per month by the end of the summer. but the u.s. is still months away from catching up with russia, which produces at least 100,000 rounds every month. do you need to step it up even more? >> i think we need to produce more. i think we need to invest more in munitions. and we're doing that. >> reporter: even with russia and north korea outproducing the u.s., the army secretary insists there is still american advantage. >>ou have to compare the quality of what the russians are producing and what they're getting, frankly, from countries like north korea. it's just not the same quality as what we're producing. >> reporter: with the war in ukraine now esntially at stalemate, defense officials say consistent ammunition anweapons supplies are more important than ever. lester? >> all right, courtney kube, thank you. in 60 seconds, in the heat of his summer tour, star justin timberlake arrested on a drunk driving charge in a famous beach down. town. what police say about the pop superstar's condition when he wa the pop superstar's condition when he wa s weathertech products are designed and manufactured in america using only american raw materials. most competitors make things seven thousand miles away... and then wonder why they don't fit. with weathertech in your vehicle you may hear angels singing as you marvel, how do they do it? simple. american technology and american workers deliver quality... not imported junk for a few bucks less. get the gold standard in floorliners and support america. voices of people with cidp: cidp disrupts. find your fit at wt.com cidp derails. let's be honest... all: cidp sucks! voices of people with cidp: but living with cidp doesn't have to. when you sign up at shiningthroughcidp.com, you'll find inspiration in real patient stories, helpful tips, reliable information, and more. cidp can be tough. but finding hope just got a little easier. sign up at shiningthroughcidp.com. all: be heard. be hopeful. be you. back now with the arrest of one of the biggest names in entertainment. justin timberlake pleading not guilty to a charge of driving while intoxicated on new york's long island. erin mclaughlin has late details. >> reporter: tonight, justin timberlake arrested and charged with driving while intoxicated. according to the suffolk county district attorney, he pleaded not guilty and was released. the singer was photographed by thedailymail.com in handcuffs, heading to court today in sag harbor, a ritzy beach community on eastern long island. a source close to timberlake tells nbc news last night the 43-year-old had dinner at the exclusive american hotel. he was driving a 2025 bmw to a friend's house after midnight when according to court documents, he failed to stop at this stop sign and swerved in two different places. police pulled him over. the officer determined timberlake was intoxicated, writing his eyes were blood shot and glassy. a strong odor of an alcoholic beverage was emanating from his breath. he had slowed speech and he performed poorly on all standardized field sobriety tests. according to the documents, timberlake told the officer "i had one martini, and i followed my friends home." he was arrested and brought to police headquarters, where he stayed overnight, having refused a chemical test to determine his blood alcohol level three times. nbc news reached out to timberlake's representatives and has yet to hear back. the performer was in sag harbor on a break from his world tour, promoting his new album. the legendary billy joel, who had lunch at the same hotel today reacting to timberlake's arrest. >> judge not lest ye be judged. >> reporter: timberlake's next concert is in chicago on friday. he is also scheduled for a virtual court date at the end of july. lester? >> all right, erin, thank you. coming up, a major move by a school district to curb cell phone use. we'll tell you where. plus, our investigation into suspected chinese organized crime groups growing marijuana in maine. the national security concerns, next. known for following your dreams. known for keeping with tradition. known for discovering new places. no one wants to be known for cancer, but a treatment can be. keytruda is known to treat cancer. fda-approved for 17 types of cancer, including certain early-stage and advanced cancers. one of those cancers is early-stage non-small cell lung cancer. keytruda may be used with certain chemotherapies before surgery when you have early-stage lung cancer, which can be removed by surgery, and then continued alone after surgery to help prevent your lung cancer from coming back. keytruda can cause your immune system to attack healthy parts of your body during or after treatment. this may be severe and lead to death. see your doctor right away if you have cough, shortness of breath, chest pain, diarrhea, severe stomach pain, severe nausea or vomiting, headache, light sensitivity, eye problems, irregular heartbeat, extreme tiredness, constipation, dizziness or fainting, changes in appetite, thirst, or urine, confusion, memory problems, muscle pain or weakness, fever, rash, itching, or flushing. there may be other side effects. tell your doctor about all your medical conditions, including immune system problems, if you've had or plan to have an organ, tissue, or stem cell transplant, received chest radiation or have a nervous system problem. keytruda is an immunotherapy and is also being studied in hundreds of clinical trials exploring ways to treat even more types of cancer. it's tru. keytruda from merck. see all the types of cancer keytruda is known for at keytruda.com and ask your doctor if keytruda could be right for you. 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[ sniffs ] yep, that's mold. well, then, let's see if we can save you some money with progressive. guess how much i originally paid for this fireplace? 23 bucks. materials and labor. just ignore him. you got bamboozled! a major move today schools. the board in the nation's second largest school district approving a strict all-day ban on cell phones for its more than 400,000 students. the ban would take effect in january. the vote coming a day after the u.s. surgeon general called for warning labels on social media. and now to our nbc news investigation. maine has become a hot spot for black market marijuana as authorities fear chinese organized crime is growing a foothold in the state. jacob soboroff has more on our series "captives of cannabis". >> this is rush hour in skowhegan, maine. >>. >> reporter: rush hour in skowhegan maine. aaron bolster has been a realtor here for what's it's like to live in this part of the country? >> it's a good lifestyle. clean air, low crime. >> reporter: but that's changed. sincy one, local law enforcement say they've raided over 40 unlicensed marijuanows acro the state at homes suspected to have ties to chinese organized crime, at least several with sales by bolster. when you realized they're starting to raid at houses you have sold, what did you think? >> wondering which is the next one? >> reporter: bolster is right. now home to grows run by chinese criminal groups, a phenomenon we've been reporting on across the country for two years, with consequences including human trafficking and money laundering. next door to that home that bolster sold, we met neighbors janet and richard gordon. how often were people present at the home? >> at the end of the month, they were loading a van and then it would take off for a few days. >> reporter: norridgewock town manager richard labelle was on the raid at this property an brought us to where authorities say they found nearly 400 pot plants. oh, wow, it's a big structure that used to be used for what? automotive repairs? . can we go look? >> sure. >> reporter: inside with electricity shut off, he showed us chemical containers, a pamphlet on hemp growing, multiple rooms built to process marijuana, and perhaps evidence of where the vans the neighbors saw may have been headed. this is brooklyn. we know from covering other organized chinese crime grows across the country, that people are coming from brooklyn to go to grows in places like oklahoma. >> yeah, very little doubt that folks are coming from the city and they're either going back to brooklyn and/or boston. >> reporter: according to property records, the house was registered in new york, a hub to chinese groups and the migrant laborers they rely on which we investigated last year. it's a connection that raises grave concerns for maine senator susan collins, who we met in washington. why is this happening? >> chinese transnational criminal groups seem to be targeting rural areas. what we don't know is it a threat to our national security. >> reporter: it sounds like you're saying this is bigger than marijuana. >> i think it is bigger than marijuana. it may be an attempt to probe our defenses. >> reporter: an attempt senator collins suspects that could be connected to chinese leadership. is it fair to say you believe xi jinping is aware of this operation? >> i do believe that. >> reporter: and has he directed it in some way? >> i don't know that, but it's impossible for me to believe that he is not aware. >> reporter: this month, the fbi director stopped short of supporting senator collins' theory. >> we don't yet see, but we're obviously investigating any direct ties between these grows and, say, the chinese government itself. >> reporter: in a statement, the chinese embassy in washington says the chinese government has taken an active and responsible approach to work with countries, including the u.s., to solve the drug problem. yet a recent congressional investigation found the chinese communist party holds ownership interest in several chinese companies tied to drug trafficking and moneylaundering. four former senior federal law enforcement officers confirmed to nbc news those schemes often include proceeds from illicit marijuana. back in maine, there are nearly 100 active grows possibly tied to chinese criminal groups according to the u.s. attorney. and just today federal authorities charged two individuals, bringing the total to three and have seized seraprerties. as a town official, do you think they're working for themselves or for a larger enterprise? >> very little doubt in my mind that they're working for a larger enterprise. >> reporter: that larger enterprise with connections around the country and the globe still coming in to focus. jacob soboroff, nbc news, norridgewock, maine. up next, a new generation brings home the hardware in the garden, extending a dynasty and making history in boston. garden, depression is a journey. i'd made some progress on my antidepressant... had some daily wins in reducing my symptoms. but i was still masking my depression. so i talked to my doctor. she told me i could build on my wins, without changing my antidepressant. rexulti, when added to an antidepressant, significantly reduced depression symptoms more than an antidepressant alone. and less depression... that's a win. rexulti can cause serious side effects. elderly dementia patients have an increased risk of death or stroke. antidepressants may increase suicidal thoughts and actions and worsen depression in children and young adults. report new or sudden changes in mood, behavior, thoughts, or feelings, or if you develop suicidal thoughts or actions. report fever, stiff muscles, and confusion, which can be life-threatening, or uncontrolled muscle movements, which may be permanent. high blood sugar which can lead to coma or death; weight gain; increased cholesterol; low white blood cells; unusual urges; dizziness on standing; falls; seizures; trouble swallowing, or sleepiness may occur. keep moving forward. ask your doctor about rexulti. hey, grab more delectables. keep moving forward. you know, that lickable cat treat? 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(♪♪) start to get yourself back, with bimzelx. ask your dermatologist about bimzelx today. finally, they're still celebrating in boston after one of the most storied franchises in all of sports brought home a record-breaking championship. here is anne thompson. >> this crowd on its feet. >> reporter: in a city where history is on every corner -- >> time to say it again, boston. anything's possible! >> reporter: the celtics add another milestone to boston's lore. >> the celtics are nba champions. >> reporter: their 18th championship, the most in the nba. a record of excellence built by bill russell, larry bird, bill walton and kevin garnett, 16 years after the last crown, and coming painfully close in the prior two seasons, jayson tatum and jaylen brown, burdened by expectations, haunted by history, vanquishing both. >> we did it! >> reporter: bob ryan's seen them all in 55 years writing for "the boston globe." >> and now they have done it, and they can pound their chest, and they can flex their muscles and they can do whatever they want. they've earned it. >> reporter: so many memorable moments. payton pritchard's impossible shots. >> the buzzer winner. >> reporter: brown lifting the bill russell trophy as mvp. >> and say this with my brothers and partners in crime, they've been with me the whole way. >> reporter: the joy of tatum, a single dad raising his son deuce. >> deuce tatum is boston's child. >> reporter: boston once again ecstatic. >> 19 next, 19 next! >> reporter: to have history repeat itself. anne thompson, "nbc news. and that is "nbc nightly news" with lester holt for this tuesday. i'm lester holt. please take care of yourself and each other. good night. a lot of smoke and some of it is drifting our way. meol