I was sitting outside by the pool just after 11pm having a smoke and was looking up at the stars as I always do at night. Quite suddenly a bright aqua blue disk shaped craft came flying over my rooftop heading south at about 800-1000 feet AGL and flew into a small stationary cloud. The UFO was about the size of a small passenger jet. I could no longer see the craft or any light from it after it went inside the cloud, however the cloud began to move rapidly to the NE over my head towards MT Lemon right after the UFO enterd into it! There was no wind whatsoever and no other clouds in the sky except for this one small cloud that had been completely stationary before the UFO flew into it. I can only speculate that the cloud was already hiding/cloaking a larger craft and the blue UFO that I saw must have joined up with it or inside of it. This is not the first time I have witnessed a craft hiding inside of a cloud before. I reported a similar event a few years ago up in the Sedona Arizona region during the daytime when I watched a very small cloud in an otherwise cloudless sky moving overhead yet stopping and starting and CHANGING DIRECTION despite the fact that there was once again no wind present at the time. I have seen dozens of UFO's here in the Arizona skies over the past 10 years and it is always a thrill to witness them. I have attempted to contact them mentally on several occasions when I have spotted them and several times they actually flashed a very bright beam of light right at me to let me know that they somehow heard me and were acknowledging my request for verification of their existence. Very exciting to know that they are here !