Staffies were bred in the UK. They are a mixture of an Old English Terrier and an Old English BullDog. This mix means that they are able to cope with a certain level of cold conditions. As the UK isn't famous for its lovely weather.
During UK winters the temperatures will often drop below 32F. And they will occasionally see snow.
Staffies are able to cope with these temperatures well. And despite being short-haired they will not need to wear coats in this weather. Or in the rain. Unless they have muscle issues, in which case their vet may recommend a coat to prevent the muscles from seizing up.