By Jamie Ross and Hannah Jewell  Email Good morning. It’s Wednesday, June 19th — also known as Juneteenth or Emancipation Day. Here’s everything you need to know about the holiday. Now let’s get to the news.   A brutal, long-lasting heat wave is intensifying across eastern states. What to expect: Scores of high-temperature records are set to be broken today from Michigan to Maine — including in Detroit, Cleveland and Boston. Follow live updates here. Elsewhere in the country: Flooding rains are expected to soak South Texas today. And a wildfire in New Mexico has burned thousands of acressince Monday. We’re tracking it here. Read this story            There’s a new most valuable company in the world. The stock values of Nvidia, Apple and Microsoft. (The Washington Post) What is it? Nvidia, the computer chip maker at the center of the artificial intelligence boom. Its stock price continued a spectacular rise yesterday, eclipsing Microsoft and Apple. The bigger picture: Nvidia’s soaring value underlines how strongly investors believe Big Tech executives’ claims that AI is about to overhaul large parts of our lives. Read this story              Baseball legend Willie Mays died yesterday at 93. Mr. Mays, shown in 1967, won 12 consecutive Gold Glove awards for defensive excellence in center field. (Malcolm Emmons/USA Today Sports/Reuters) How we’ll remember him: As arguably the greatest player in major league history. The all-star center fielder played for the New York and San Francisco Giants in the 1950s and ’60s. He could do it all: Mays combined power, speed, arm strength, wizardry with a glove — like this miraculous catch — and steady hitting, with 660 home runs. Read this story            Robert F. Kennedy Jr. won’t qualify for CNN’s presidential debate next week. Why? The independent candidate doesn’t appear on enough statewide ballots to qualify, a Post survey found. The debate between President Biden and Donald Trump is set for June 27. Other election news: Virginia and Oklahoma held Democratic and Republican primaries yesterday. Find full results from Virginia here and full results from Oklahoma here. Read this story            ADVERTISEMENT     Justin Timberlake was arrested on a DWI charge in New York yesterday. What we know: The singer was stopped in the Hamptons after ignoring a stop sign and failing to stay in his lane, police said. He appeared in court and was later released. What now? He is due for a virtual court hearing next Wednesday for the intoxicated-driving charge. The Grammy-winning artist is on a world tour, which stops in Chicago this Friday. Read this story            A panel of health experts recommended interventions for children with high BMI. The advice: For doctors to refer children and teens with a high body mass index to programs that can guide them on healthy eating, exercise and understanding food labels. One question: Some experts say the task force should consider recommending weight-loss drugs for children. But the guidelines, released yesterday, said more research is needed. Read this story            Astronomers may be witnessing the awakening of a black hole for the first time. An artist’s rendering shows the material being pulled in by the black hole as it feeds on the gas in its surroundings, making the galaxy light up. (Martin Kornmesser/European Southern Observatory) What to know: Astronomers had been watching a galaxy far, far away for a long time. It seemed unremarkable — but, in December 2019, it suddenly started shining bright. So what’s going on? A black hole appears to be waking up and sucking in gas, creating a light show, an upcoming paper says. But it could be something else, like a star being torn apart. Read this story