The spell creates a 20-foot-radius sphere of mist similar to a fog cloud spell centered on a point you can see within range. The cloud spreads around corners, and its area of effect is heavily obscured. A wind of moderate or greater speed (at least 10 miles per hour) disperses it in one round. The fog is freezing cold; any creature that ends its turn in the fog takes 2d6 cold damage and gains a level of exhaustion; a successful Constitution saving throw halves the damage and prevents the exhaustion.