What does a solid yellow X mean in reversible lane usage?

A solid yellow X in reversible lane usage signifies that the lane is no longer safe for travel and that drivers must move out of the lane. This symbol is used to indicate a change in traffic conditions, alerting drivers that the lane is becoming either unavailable or is being reserved for specific types of vehicles or directions. The solid yellow X acts as a warning to ensure that drivers do not inadvertently enter a lane that could lead to accidents or traffic violations. Recognizing this signal is crucial for maintaining safety on the road, especially in areas where lanes may shift directions based on peak traffic flow.