What immediate action should a lifeguard take when they hear thunder in the distance?

When a lifeguard hears thunder in the distance, the immediate action they should take is to clear patrons from the water. This is because thunder signifies the possibility of a storm, which can bring lightning. Lightning poses a significant risk to anyone in or near the water, as water conducts electricity, and individuals in the water are especially vulnerable during a storm.

Clearing the water ensures the safety of all patrons by removing them from a high-risk situation. It is crucial to act promptly because the threat of lightning may escalate quickly, and taking immediate action minimizes the risk of injury. Lifeguards are trained to prioritize the safety of swimmers and must respond rapidly to weather-related hazards to protect everyone at the facility. Other options may involve steps that are important but are not as immediate or life-saving as removing patrons from the water when thunder is heard.