Saturday’s qualifying session was cut to from two rounds to one due to an extended weather delay, but it was still run in groups.
The top five speeds from each group were placed in the top 10 starting lineup, with the fastest speed of the 10 earning the pole.
Larson, who won last weekend’s race at Sonoma for his third victory of the 2024 season, ended up going out last in Group B, which produced much faster speeds than Group A.
Larson’s lap at 136.458 mph easily topped the second group and was fastest overall, which gave him the pole for Sunday night’s inaugural Cup race at Iowa.
It’s the fourth pole of the season for Larson and 20th of his career.
“It was challenging, for sure,” Larson said of his qualifying attempt. “It wasn’t as challenging as I was expecting. I had just watched everybody (go before me) and everybody was really loose and on edge. I just tried to be under the edge a little but, I guess.
“My lap felt fairly smooth and a little edgy but nothing as bad as I was expecting. It helped to go last, it helped to be able to watch everybody, got to talk with Cliff (Daniels, crew chief) before I went out.
“Happy to get the pole. I was hoping for rain and didn’t know how we would qualify.”
Reigning series champion Ryan Blaney ended up second (136.311 mph), Josh Berry third, William Byron fourth and Brad Keselowski rounded out the top five.
Completing the top 10 starting lineup are Chase Briscoe (who was fastest in Group A), Kyle Busch, Tyler Reddick, Chase Elliott and Christopher Bell.
Bell and Austin Cindric both had to move to backup cars following accidents in Friday’s practice so both will have to start Sunday night’s race from the rear of the field.
Round 1 / Group B
Almost everyone in the second group ended up faster than those in the first and Larson led the way at 136.458 mph.
Blaney was second fastest (136.311 mph) and Berry third (135.916 mph).
Also advancing to the top 10 from the group were Byron and Keselowski.
Among those who failed to advance were Joey Logano, Daniel Suarez, Martin Truex Jr. and Alex Bowman.
Round 1 / Group A
Briscoe was among the first 10 cars to hit the track and ended up posting the top average lap speed of 133.046 mph, setting a high benchmark from the start.
Busch was second quick in the group at 132.928 mph and Reddick was third (132.872 mph).
Also moving on to the top 10 starting lineup from Group A were Elliott and Bell, who were fourth and fifth-fastest.
Among those who failed to advance were Denny Hamlin, Todd Gilliland and Bubba Wallace.