What is the meaning of air defense warning conditions?

(DoD) A degree of air raid probability according to the following code. The term air defense region/sector referred to herein may include forces and units afloat and/or deployed to forward areas, as applicable. Air defense warning yellow - attack by hostile aircraft and/or missiles is probable. This means that hostile aircraft and/or missiles are en route toward an air defense region/sector, or unknown aircraft and/or missiles suspected to be hostile are en route toward or are within an air defense region/sector. Air defense warning red - attack by hostile aircraft and/or missiles is imminent or is in progress. This means that hostile aircraft and/or missiles are within an air defense region/sector or are in the immediate vicinity of an air defense region/sector with high probability of entering the region/sector. Air defense warning white - attack by hostile aircraft and/or missiles is improbable. May be called either before or after air defense warning yellow or red. The initial declaration of air defense emergency will automatically establish a condition of air defense warning other than white for purposes of security control of air traffic. Also called ADWCs.