While in flight, an alternating red and green light directed at you from the control tower means what?

The alternating red and green light from the control tower specifically signifies that the pilot should exercise extreme caution. This signal is primarily used to alert an aircraft of potential hazards in the area. It indicates that there might be circumstances—such as weather changes or other traffic—that require the pilot to be highly vigilant and prepared to take necessary actions to ensure safety.

This signaling is vital in maintaining situational awareness and preventing potential conflicts with other aircraft or obstacles. It is crucial for pilots to understand the implications of this light signal to respond appropriately in dynamic flight environments.