Sunlight—Days of Sunlight in Tucson
The average number of clear days per year in Tucson is 196.3. partly cloudy days are 89.5 and cloudy days are 79.5.
Source:
The weather handbook: a summary of climatic conditions and weather phenomena for selected cities in the United States and around the world Conway, H. McKinley (Hobart McKinley).
Publisher Norcross, Ga.: Conway Data, 1990. Page 79.