Fall weather that is just chilly enough for a sweater, but not cold enough for a coat. It is the perfect sweater weather. Most people enjoy sweather because of the juxtaposed chilliness of the face and hands with the warmth of the body under the sweater, much like people enjoy a warm blanket in a cold room. Very few geographical locations experience perfect sweather for long periods of time, so sweather is usually accompanied by a lot of talk about the beginning of sweather, upsales in sweaters, and a rise in talk of fallfashion.
Fashion aware boy: It's perfect sweather outside, I can't wait to walk around and show everyone how good I look!