Elevations in the Park range from 700 feet above sea level to over 8,000, providing a wide range of climatic conditions, that follow the four seasons.

Be prepared for very warm weather in the summer months, in particular in the river valleys. The spring and fall are moderate and comfortable. Winter conditions can be severe in the higher elevations, with snow and ice making travel difficult and dangerous.

For comprehensive weather information at all of the park's sites, please visit the National Weather Service Western Region to get forecasts for the areas that you will be visiting.