It is possible to be a cold air funnel, but it is tough to tell the details from these photos (plus no video to see any motion). It could also be an enhanced area along the leading edge of the rain curtain associated with the shower.
Those large mulch piles should be moved around often to mix it up to keep it from getting to hot in the middle, thus keeping the fire threat much reduced.
So much pollen! There a solid coating of it on everything. You know the pollen is bad when you can see tire tracks in your driveway because of a layer of pollen.