Which of the following codes would indicate a thunderstorm with heavy downpours?

The code indicating a thunderstorm with heavy downpours is represented by "TS W MOV E." In this context, "TS" stands for thunderstorm, and the additional elements convey the nature and movement of the storm. The "W" signifies that the thunderstorm is associated with heavy precipitation conditions, while "MOV E" indicates the movement of the storm to the east. Therefore, this code effectively communicates that not only is there a thunderstorm present, but it is also characterized by substantial rainfall.

Understanding the context of the other options highlights their relevance in different weather scenarios. For instance, "GR 2" refers to 2-inch hailstones, which specifically denotes hail, not necessarily related to heavy rainfall. "CB W MOV E" describes a cumulonimbus cloud (often associated with thunderstorms) that is moving east, but it does not explicitly indicate heavy precipitation. Lastly, "SNINCR 1/4" indicates a snowfall increment of a quarter inch, which relates to snow rather than thunderstorms and heavy downpours. Each code serves a specific purpose in weather reporting, but in this case, the selected code accurately encapsulates the conditions of a thunderstorm with heavy rainfall.