The metro area has been promising 300 days of sunshine a year since the 1870s, around the time Littleton was founded. While this railroad-marketing myth is a tad high—you can expect about 250 days of sunshine—one thing remains true: If you don’t like the weather here, wait five minutes and it will change. In this high, dry climate impacted by mountains, weather can swing 40° a day, so layer up!