about his efforts to get sober before buying the gun at the center of the case. the outrage in israel. the u.n. adding it and hamas to a blacklist of those who harm children in war zones. new body cam video from the arrest of the world s number one golfer, scottie scheffler. what it reveals. and team usa stunning the world with a historic win. is america catching cricket fever? announcer: this is nbc nightly news with lester holt. good evening, and welcome. in this season of extremes and heightened weather danger we ve witnessed these last several weeks, it s now the crippling heat we re watching tonight taking hold across a wide stretch of the southern tier putting 21 million people under heat alerts today. in the past 24 hours, triple-digit temperatures being recorded in places that include phoenix and las vegas. near record high temperatures could occur as far east as miami. tonight, first responders are adopting some of the lessons from last year s deadly summ