Upslope fog is a type of fog that forms when moist air is lifted over a mountain or hill. As the air rises, it cools and condenses, creating tiny water droplets that make up the fog. This phenomenon is common in mountainous regions, especially when warm, moist air meets cooler elevations. The process typically occurs when winds blow moist air from bodies of water or lowlands up the slopes of mountains. The resulting fog can reduce visibility and create damp conditions, impacting travel and outdoor activities. Upslope fog is often seen in areas like the Rocky Mountains and Appalachian Mountains.