Neither snowy winters nor steamy summers will effect this timer with a protective cover. It works in temperatures as low as -40 degrees Fahrenheit and as high as 104 degrees Fahrenheit. Use this heavy duty outdoor timer to save energy in your light displays. Two settings per day allow you choose when you want your lights on and off. There is also a 24 hour manual setting in case you need make short term changes in your lighting schedule. It has 12" lead cord just in case an outlet is not nearby.