Powder cloud refers to airborne snow traveling up to what speed?

• A. 60 mph
• B. 240 mph
• C. 180 mph
• D. 120 mph

Answer: (C)

Powder cloud describes the fast-moving plume of airborne snow created by a high-energy avalanche. The speed that best represents how fast this cloud can travel is about 180 mph. This figure comes from observations of powder clouds reaching high velocities before air resistance slows them down, making 180 mph a commonly cited upper range in practice.

Lower speeds like 60 mph or 120 mph underestimate how far and how quickly the cloud can project snow, while 240 mph is beyond what's typically observed for most powder clouds. So 180 mph accurately captures the practical upper bound of airborne snow in most avalanche events.