Analyzing the cloudiness data of 500 cities, there is no obvious relationship between latitudes and cloudiness. However, these are worth noticing facts:

• More clouds concentrated at latitudes of >30-deg North and <0-deg.
• "Zero", ~76%, ~90% cloudiness are most likely to occur.
• No cloudiness observation >80-deg North and <60-deg South. This is could be due to the fact that no weather station or city available nearby at these locations.