Respuesta :
Before a tornado strikes, the wind may die down and the air may become very still. A loud roar similar to a freight train may be heard. An approaching cloud of debris, even if a funnel is not visible.
Answer:
A dark, often greenish sky
Before a tornado strikes, the wind may die down and the air may become very still.
A loud roar similar to a freight train may be heard.
Explanation: