The Olympic mountains and Cascades compound this climatic pattern by causing orographic lift of the air masses blown inland from the Pacific Ocean, resulting in the windward side of the mountains receiving high levels of precipitation and the leeward side receiving low levels. This occurs most dramatically around the Olympic Mountains and the Cascade Range. In both cases the windward slopes facing southwest receive high precipitation and mild, cool temperatures. While the Puget Sound lowlands are known for clouds and rain in the winter, the western slopes of the Cascades receive larger amounts of precipitation, often falling as snow at higher elevations. Mount Baker, near the state's northern border, is one of the snowiest places in the world. In 1999, it set the world record for snowfall in a single season—.