Regardless of what car I've owned, I've found rattles that come and go depending on outdoor air temperature. Some rattles only occur if the temp is below 20 degrees. Other rattles that occur only when the temp is between 40 and 50 degrees. As different parts expand and contract, they pass through stages that cause them to rattle or not.
I don't think I've ever owned a car that NEVER rattled regardless of temperature. I don't let these rattles bother me very much. The only time I get annoyed is when I have a rattle that occurs at ALL temperatures. Those are the rattles that I try to track down and fix.