"This is an achievement I never thought I would see in my lifetime," NPD analyst Matt Powell wrote in the press release.
Part of the story is Adidas' continued rise in North America. Last month, Adidas sales grew by 50% compared with August 2016, and its sneaker share nearly doubled to 13%, according to NPD data.
In its last earnings report, the company said sales in North American had grown 31%.
Its top selling models are the throwback Adidas Superstar and the futuristic lifestyle shoe Tubular Shadow.
The other half of the story is Jordan's continued stagnation. The Nike brand has been suffering for a while now, a problem that Morgan Stanley analysts have called "previously unthinkable."
Jordan has been struggling amid an industrywide downturn in sales of basketball sneakers. The trends are now favoring low-top sneakers like the Adidas Superstar, as the chunkier looks of basketball shoes don't quite fit in with skinny jeans and joggers.
To remedy the issue, Nike has been releasing more and more Jordan shoes, including re-releases of vintage styles. Now, when Jordan shoes are released, they do not always sell out instantly. That has eroded the brand value of Jordan, which has long-term implications for the company, according to Josh Luber, CEO of the sneaker-resale platform StockX.
Nike as a whole is still the top sportswear seller in the US.