It only rains about one day in October in Los Angeles. That’s what Ben Winston discovered in his research earlier this year as the producer began to scope out the best possible dates to stage an Adele concert special at the Griffith Observatory.

Winston, executive producer of the CBS special “Adele: One Night Only,” which scored more than 10 million viewers in its debut on Sunday, revealed that the carefully laid plans for the special were redrawn quickly when it became clear via weather radar about 72 hours before that it was definitely going to pour on Oct. 25, the day that was originally scheduled for the performance.

Adele was cool with the decision to move the concert up by a day to Oct. 24. For Winston and the crew, that meant two long nights of working around the clock to prepare the space. It also required a mass outreach to the hand-picked guest list of about 300 people.

“We called everyone on a Friday to say ‘Hi, thanks for coming to our show. Do you fancy coming in 48 hours instead of Monday?'” Winston told Variety.

Given the chance to see Adele perform for the first time in years in an intimate setting, there weren’t many no-shows.

“Eventually what everybody watched was our dress rehearsal,” Winston said. “Adele was so great. She’s never fazed by anything and it all just happened.”

Guests took a shuttle bus from Griffith Park to the observatory. When they arrived to the seats set out in front of the the iconic building, cocktails were passed around but otherwise the setting was just like any concert.

“Adele: One Night Only” drew rave reviews for the gorgeous aerial drone footage that showed the Griffith Observatory, the Hollywood sign and the bright lights of the Los Angeles basin below. Winston said the credit for delivering “a love letter to Los Angeles” belongs to Gabe de la Parra, the drone operator hired for the shoot, and “One Night Only” director Paul Dugdale.

When Winston got his glimpse of the footage de la Parra was collecting, he knew it was worth the effort. “It was just one of those pinch-me moments,” he said. “You’re looking over the whole of Los Angeles looking beautiful. It’s impossible not to feel grateful just for getting to do this.”

Planning for the special also accounted for a decision to include a surprise marriage proposal from two Adele super fans. That idea was sparked by the fact that proposals are not uncommon sights at Adele concerts.

Producers put ads in local media seeking men who were looking to propose to their girlfriends in a “spectacular way” but had no reference to Adele. Respondents were asked to name their favorite artists as part of a series of questions about pop culture. Those who listed Adele as their fave-rave were saved for the short list.

Quentin Brunson was the final choice simply because he charmed the production team. “He’s such a sweet and lovely man,” Winston said. His now-fiancee Ashleigh Mann was truly shocked by the move. The sequence was edited down considerably for the special.

Brunson didn’t find out that he would be making the proposal during the middle of an Adele concert until the day before.

When Brunson walked a blindfolded Mann into the venue after Adele asked the crowd to be quiet, Brunson was actually frightened by her reaction.

“She could hardly speak,” Winston said. “We had to cut that carefully to get it to be sharper. The only thing I wish we’d captured a little bit more of was how the crowd was all in tears.”

Winston’s Fulwell 73 banner was behind the concert production, along with Adele’s Onward banner, as well as the interview segments of the two-hour special that were recorded at Oprah Winfrey’s home in Montecito, Calif., produced with Winfrey’s Harpo banner. The weight of working with two of the world’s most recognizable superstars was not lost on Winston and his team.

“It was just one of those moments when you feel very lucky to be able to make stuff like this,” Winston said. “We’re so glad so many people watched it. It’s great that you can still have these moments where network television brings people together for a special TV moment. We’re all in it for those moments.”