The weather in Glen Canyon National Recreation Area is usually typical for the high deserts. Summers are extremely hot with little, if any, shade. Winters are moderately cold with night time lows often below freezing. Spring weather is highly variable and unpredictable with extended periods of winds. Fall weather is usually nice and mild, a great time to beat the heat (and the crowds!).
Temperatures can range from 110° F (38°C) in June & July to O° F (-16°C) in December & January. Precipitation is generally light (less than 6 inches--15.2cm-- annually) though heavy rains and flash flooding is possible during the summer and fall "monsoons."
We recommend lightweight, light colored clothing for summer, including a hat. Layers of clothing are best for other times of the year.