Blizzard

You create a 20-foot-radius sphere of dense mist and snow, centered on a point within range. The cloud spreads around corners, and its area is heavily obscured. The cloud lingers in the air for the duration.

Each creature that is completely within the cloud at the start of its turn must make a Constitution saving throw against frostbite. On a failed save, the creature’s movement speed is reduced by half for as long as it remains in the blizzard. Creatures in the blizzard zone progressively take cold damage equal to the number of turns they have spent in the blizzard.

A moderate wind (at least 10 miles per hour) disperses the cloud after 4 rounds. A strong wind (at least 20 miles per hour) disperses it after I round.