Death Valley is a place of extremes. Below sea level basin to towering mountain elevations. The variety of landscape makes Death Valley at top of many peoples list. Because of the extreme changes in elevation the temperature can be just as extreme. Death Valley has earned its name. Avoid visiting during the summer months, it is WAY too hot during that time, well for me anyway.
During January there is frost on the dunes and cold temperatures during the night. Spring or Fall are better times to visit; (especially if camping) when night time temperatures stay above freezing.
Death Valley is beautiful and worth a visit.