large metallic disc over central tucson in thunderstorm

One night during a thunderstorm in july 1976, while watching lightning striking outside, thru the south side facing back door window of family house at age 8, I saw a very large (300+feet diameter) metallic disc floating stationary inside of the thunderstorm.  
It had lights around outside bottom of disc, and 4 hemispherical protrusions, and bright bluish light in the center bottom.
I was totally amazed to watch the lightning strike the craft several times, and noticed when the light reflected off the highly polished metallic surface.  
I yelled for my mother, who came running, and we then watched the craft for about 3 or 4 minutes through the backdoor window.  Then it slowly moved upwards thru the clouds and vanished. 
My father, who was retired from air force 3 years earlier, was told the story next day, and was very interested.  I remember parents talking about an article in the local newspaper the following day, where hundreds of people saw the same thing.  
I have never been able to find article, but i know what I saw, and it was the real deal, an unforgetable experience.
Witness indicates that the date of the sighting is approximate.  PD