Weather will likely play an important role when you plan your trip to Sardinia, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually August and July with an average temp of 78°F, while the coldest months are January and February with an average of 50°F. The rainiest months in Sardinia are November, December, January, and October, with each month seeing an average of 9 inches of rainfall.