Question

Why do high-altitude clouds tend to appear before a warm front arrives in a region?

Answer 1

Answer:

Global Warming

Explanation:

That's why

Answer 2

Cold air is more dense than warm air, so when a warm air mass meets a cold air mass, the cold air ends up below the warm air. Once the air has risen, it cools and clouds can form. Warm fronts produce clouds when warm air replaces cold air by sliding above it,

Hope this helps :)