overdressed

I may be overdressed, being mildly bundled up in a fleece while it is 75 degrees outside. I don't feel silly because there are lots USC undergraduates ambling about campus in sweatshirts and jackets. The weather was cool all day yesterday, and last night's observed low was a chilly 42 degrees. The temperatures for tomorrow, December 4, are forecast by weather.com to include a high of 79 degrees. We are all confused.