Rainfall/ Precipitation in Cleveland, Ohio, Usa Cleveland, Ohio is bestowed with an average of 930.4 mm (36.6 in) of rainfall per year, or 77.5 mm (3.1 in) per month. On average there are 151 days per year with more than 0.1 mm (0.004 in) of rainfall (precipitation) or 12.6 days with a quantity of rain, sleet, snow etc. per month. The driest weather is in January when an average of 51.8 mm (2 in) of rainfall (precipitation) occurs.