Precipitation is a package for creators to add rain, snow, and potentially other weather effects to their maps in Deus Ex.
Another quick test on Liberty Island, this time with a SnowZone. Shelter zones use the weather effects of the PrecipitationZone they inhabit, so if I had set any up before with the rain, swapping out the main PrecipitationZone for a SnowZone would have required no additional modifications to the shelters.