If air is stable, what is the expected surface visibility?

• A. Poor
• B. Good
• C. Variable
• D. Excellent

Answer: (A)

Stable air suppresses vertical mixing, acting like a lid on the atmosphere. With little vertical air movement, moisture, smoke, and other particles tend to stay near the surface, so fog or haze can form or persist. That reduces how far you can see at the ground, making surface visibility poor. Unless other factors drastically clear the air, stable conditions generally lead to reduced visibility, which is why this best matches a poor surface visibility.