Why would ice crystals form in cold dasani water poured into a room temperature glass?

My wife brought in the bottle of Dasani water from her car. It was below freezing outside. She poured it into a room temperature glass and ice crystals resembling snowflakes formed until the glass was filled with an icy slush.

We watched if for some time and couldn’t come up with a good explanation. Then we tried a second room temperature glass. The water while contained inside the plastic dasani bottle was free of ice and when we poured the second glass it too began to form ice crystals.

I recorded the second pour on video that I can post on you tube if anyone wants to see it.