Heavy snow blanketed Southern Arizona on Wednesday. By sunrise on Thursday, the GOES weather satellite took this visible image.
Source: National Weather Service - Tucson
The official total in Tucson was a trace, which tied the record for snow on that date. The old record was a trace of snow in 1971.
The green in the picture is where there are low clouds covering the snow on the ground.
The most snow Tucson has seen in February is 4 inches on Feb 13th 1908.