Big Round Circle UFO Sighting, A.M.

I was driving W on Guadalupe Rd. in Mesa, AZ, from Ellsworth Rd.  As I was driving I noticed off in the distance, above a Walgreens, positioned SE what appeared to be a black hot air balloon. It was big and barely moving, if at all. 
 As I was looking at it, slowly, my skepticism grew.  As I drove for another 5-6 seconds, I considered turning on and grabbing my video camera that I had in the car with me. I am doubtful when it comes to a UFO sighting (I've always wanted to see one) so I feel as if my mind plays tricks on me.  
This was no trick.  It was huge.  And as I drove with smy head out my drivers side window and stared, I rolled through a light.  
There were 3 ladies out running on the corner, and they had stopped to wait for the light.  I looked at them to see if they were seeing what I was seeing but it did not seem like it.  
The UFO hadn't left my sight.  So I turned my camera on and pulled into my neighborhood.  As I drove in, the houses blocked the UFO.  
When I returned to open road, couldn't have been more than 25-30 seconds, it was gone from sight.  It was then that a weird feeling started to kick in, almost of disappointment.  
It was huge in the sky. Impossible to miss.  Looked like a big black ring with a weird center type and a little tiny upside down triangle on the bottom.  
As soon as I saw it, it seemed to be gone.  I wish I would've shot a photo or shot some tape of the UFO but it was all over so fast.  
Still hard to believe. 
((name deleted))
Witness elects to remain totally anonymous; provides no contact information.  PD