What indicates that a Towering Cumulus (TCU) cloud may produce showers?

The distinctive cauliflower top of a Towering Cumulus (TCU) cloud is an indication that the cloud has significant vertical development. This characteristic morphology suggests strong updrafts within the cloud, which can lead to the formation of larger precipitation particles. As these updrafts develop, moisture within the cloud can condense and accumulate, eventually overloading the cloud's ability to hold the water, resulting in the production of showers. The more pronounced and developed the cloud's top, often resembling a cauliflower, the more likely it is to produce precipitation as it signifies that the cloud is in a vigorous growth phase, potentially leading to further development into more severe weather patterns.

In contrast, a smooth, flat base typically signifies stable atmospheric conditions, while common occurrence at sunset does not inherently relate to the cloud's potential for rain. Lastly, while wind shear can influence storm development, it does not specifically indicate whether a TCU will produce showers directly.