I've seen this phenomena only 3 times in my lifetime. Last night Tucson had an incredible lightning show, which is typical during our "monsoon" season. However, there were several episodes of the surface atmosphere glowing an incredible blue-green prior and during CG strikes. Sometimes the ground and surrounding atmosphere lit up in these colors without any visible strikes near them. The manner in which the colors manifested was similar looking to the northern lights...however much closer to the surface. Please....can anybody answer this??? All of Tucson is in a buzz about it....and they're all looking to me for an answer. Help!