What does it mean when the yellow lights are flashing on the road signs?
When the yellow lights are flashing, it indicates that there is a message being broadcast. On this message, could be information on construction, emergencies and traffic incidents. This information can also be found on the Thruway's Highway Advisory Radio(HAR)stations. See link below.
NYS Thruway Authority
Information about the NYS Thruway and Highway Advisory Radio