Which type of cloud often brings precipitation and is thicker than cumulus clouds?

Cumulonimbus clouds are known for their towering structure and are associated with thunderstorms, heavy rain, and severe weather. However, nimbostratus clouds, which are the correct answer, are characterized by their thick, uniform, and extensive formations that cover the sky and are primarily responsible for continuous, steady precipitation.

Nimbostratus clouds form in stable air and can bring light to moderate rain over extended periods. Their thickness allows them to block sunlight, resulting in a gray, overcast sky.

In contrast, while cumulonimbus clouds can bring significant precipitation, they are typically more associated with convective storms and are not as extensive as nimbostratus clouds. Cirrostratus clouds are thin and wispy, generally indicating fair weather or the approach of a warm front, and while they can cause drizzle, they are not associated with heavier precipitation. Stratocumulus clouds, while thicker than cumulus clouds, are usually not associated with significant precipitation unless they evolve into a different type of cloud.

The key differentiator for nimbostratus clouds is their ability to produce prolonged, consistent precipitation, making them the cloud type that aligns with the characteristics described in the question.