What is a common indicator of a storm surge occurring?

A common indicator of a storm surge occurring is an unusual rise in water levels along the coast. Storm surges are primarily caused by the strong winds associated with storms, particularly hurricanes, which push seawater toward the shore, creating an increase in water levels. This rise can lead to coastal flooding, especially if the storm coincides with high tides. It is crucial to recognize this phenomenon because it poses significant risks to coastal communities.

In contrast to the other options, high-velocity winds and heavy rainfall do accompany storms but are not definitive indicators of storm surge specifically. Stable temperatures and clear skies would typically indicate calm weather conditions, not a storm surge scenario. Low pressure systems moving away from the coast can alter weather patterns, but they do not directly correlate with storm surge occurrences. Therefore, identifying an unusual rise in water levels is the most relevant indicator when assessing the potential impact of storm surges.