Summers are generally of short duration with pleasant warm days and cool nights. Freezing temperatures can sometimes occur during summer months. Summer thunderstorms with lightning and hail occur almost daily. Typically they begin mid-day and last through the afternoon. The safest places are within buildings or your automobiles. Sub-zero lows are common in the winter; dress in warm layers to keep dry and to prevent hypothermia. The altitude is 8,500 above sea level so pace yourself in any season, drink a lot of water, and use sunscreen.