Moisture coming with Pacific Ocean air is lost over the mountain ranges as precipitation before moving into the area, while air from the Arctic flows uninterrupted into the region. Due to cold air drainage, the river valley is often completely filled with stratus and fog while outside the valley is clear. The fog usually clears in a few hours. Winds in town are channeled along the Peace River valley (towards the northeast or southwest) while winds outside the valley are quite variable. During both summer and winter, the wind patterns outside the valley are mostly from the southwest or north. The passage of a migratory low to the north of Peace River will cause southwest winds to shift around to the north.