 As fronts approach, they are forced upward by the peaks of the Cascade Range, causing them to drop their moisture in the form of rain or snowfall onto the Cascades (Orographic lift).As a result, the west side of the Cascades experiences high precipitation, especially during the winter months in the form of snowfall.During winter months, weather is usually cloudy, but, due to high pressure systems over the Pacific Ocean that intensify during summer months, there is often little or no cloud cover during the summer.