cold front

A zone separating two air masses, of which the cooler, denser mass is advancing and replacing the warmer.

Cold front Any non-occluded front that moves in such a way so that colder air replaces warmer air; the "leading edge" of a relatively cold air mass.

A weather condition accompanied by high, clear skies, and a sudden drop in temperature.

A zone separating two air masses, of which the cooler, denser mass is advancing and replacing the warmer.