Nothing could bring 8-year-old Isaac Streff down. Not the soupy humidity and storms. Not the 20-minute line to get up the escalators. Not even his little sister Lydia's spunky antics.

Isaac woke up Saturday morning in an unshakably good mood, eager to see in person the new home of a team he watches religiously.

"Adrian Peterson is the best," Isaac said matter-of-factly, standing in his Minnesota Vikings jersey amid throngs of visitors crowding the second level of the newly minted U.S. Bank Stadium in downtown Minneapolis.

Isaac and his family traveled from Rogers to tour the behemoth during the weekend open house, which runs through Sunday.

For stadium officials, who expected about 90,000 visitors on Saturday alone, the day didn't go exactly according to plan — at least not according to Plan A.

Storms drove crowds, hunkered under umbrellas and rain ponchos, inside the stadium, with visitors packing entryways and spilling into the purple seating around the field.

"We're just allowing people to sit in the stands, wait out the rain and take in the view," said Michele Kelm-Helgen, chairwoman of the Minnesota Sports Facilities Authority." We saw rain in the forecast and decided to make a Plan B days ago."

That plan included setting up concessions indoors and allowing the hordes of soggy visitors to move inside the stadium for a stretch. Originally, officials intended for ticket holders to be in the stadium only during their designated tour hour and then move to Commons Park for outdoor festivities.

But morning and afternoon downpours scrapped the live music lineup and the promise of 50-foot Ferris wheel rides at the park, at least for a while. The hope, Kelm-Helgen said, was to restart the activities once the weather cleared and hope for sunny skies on Sunday.

Stadium officials anticipate more than 160,000 visitors passing through the stadium over the weekend, based on advance ticket counts. Tickets to the free open house are still available on Ticketmaster for both Saturday and Sunday.

Though damp, visitors, including the Streff family, appeared buoyant, eating hot dogs and exploring the dramatic views on each level of the facility.

Austin LaMotte, 13, made sure to capture some of these views and text his friends in Apple Valley photos from the tour. He said he's the first among his buddies to see the stadium in person.

Austin, wearing his Vikings socks, said it was a "big deal" when his grandparents told him they were taking him and his brother to Minneapolis for the open house.

"I love that the logo takes up half the field," Austin said, adding that he hopes to catch a game in person this year.

Perhaps the biggest challenge facing football enthusiasts was making it through the excited hordes inching to the escalators.

As Jose Oller waited for the ground-level escalator in a muggy pack of visitors near the entryway, he described reaching the next floor as "mission impossible."

But Oller, a Vikings fan since 1980, was undaunted. He wanted to eye the new field from his season ticket seats, in Section 314.

Week by week, Oller, of Edina, has kept up with the progress of the stadium construction online, and the $1.1 billion colossus didn't disappoint in person, he said.

"The team needs to live up to the standard of the stadium now," Oller said, gazing up at the expansive ceiling. "And I think they will."

Hannah Covington • 612-673-4751