Johnson County's Climate
Johnson County has 167 frost free days. The hottest month of the year is July. July has an average temperature of 70.2 degrees Fahrenheit. December is the coldest month. The average temperature in December is 35.2 degrees Fahrenheit. Johnson County receives 55 inches of precipitation annually. Seventeen inches of this is in the form of snow. The coldest recorded temperature in Tennessee was on December 30, 1917 in Mountain City. The temperature was minus 32 degrees Fahrenheit.