It is possible for the balloon to change its altitude and then pick up different wind directions and velocities.
https://x.company/projects/loon/
> To identify helpful wind patterns, Loon used advanced predictive models to create interactive maps of the skies. These maps allowed the team to determine the wind speed and direction at specific altitudes, times, and locations. The team then developed smart algorithms to help determine the most effective flight paths through the varying wind layers. With the aid of these algorithms, the balloons could accurately sail the winds over thousands of kilometers to reach a desired location and remain clustered around those destinations in order to deliver consistent connectivity below.
And https://x.company/blog/posts/drifting-efficiently-through-th... gets into it more.
I've tried multiple different levels from 090 to 520, and it seems the deviation within level is extremely minimal.
i.e. maybe a difference between 70deg and 75deg, but if it's going in the general direction of east, there's not an altitude to turn around or even sidetrack.
Look at +6 hours at GPI (Glacier Park in Montana). At 34,000 its easterly at 24,000 its westerly.
A balloon can only navigate by catching different winds at different altitudes. When you can control the altitude from 60,000 feet to 120,000 feet there is a significant amount of variation in the direction of winds.
https://www.govtech.com/question-of-the-day/what-is-now-stee...
https://blog.x.company/drifting-efficiently-through-the-stra...