Mystery

We had some new snow in the morning, it didn't stay very long but it was still there when I let the cat out. Sometimes she is a bit hesitant, especially if there is snow the stairs. Usually she sits along the edges for a while, perhaps to "take it all in" before she walks down the steps out in the garden. Shortly after I closed the door, there was a rumble out there and when I looked the cat was nowhere to be seen and she left these tracks. 
Has anyone a good script to what happened there?