Use of the Term CAVOK

The term “CAVOK” (KAV-OH-KAY) may be used in air-ground communications when transmitting meteorological information to arriving aircraft.

CAVOK refers to the simultaneous occurrence of the following meteorological conditions at an airport:

• No cloud below 5,000 feet, or below the highest minimum sector altitude, whichever is higher, and no cumulonimbus
• A visibility of 6 SM or more
• No precipitation, thunderstorms, shallow fog, or low drifting snow

This term, coupled with other elements of meteorological information, such as wind direction and speed, altimeter setting and pertinent remarks, will be used in transmissions directed to arriving aircraft and, where applicable, in the composition of ATlS messages. A pilot, on receipt of CAVOK, may request that detailed information be provided.

CAVOK does not apply to the provision of meteorological information to en route aircraft and, therefore, will not be used when such information is transmitted to aircraft engaged in that particular phase of flight.