Well, let's take a more general look at what a cold front is before answering that question. A cold front is essentially the line between a colder airmass and a warmer airmass. Keeping that in mind, the most basic answer is that the temperature decreases suddenly. Other changes might also take place; because these cold fronts cause warm and cold air to meet, heavy rain or snow might occur. It might get quite windy, due to changing air masses (technically atmospheric pressure but simplifying).
What happens after a cold front depends on the nature of the airmass. Is it immediately followed by a warm front? If not, where is it coming from? If it's coming from the direction of a body of water, rain or snow might continue after the front. If not, the weather will likely be cooler/colder and dry. It usually depends on the region, the season, the quality of the cold front, etc; but these are the general patterns.
Temperature is lowered. Humidity is increased in a cold front.
it gets destroyed
it starts to get coldthunder and lightning
When a cold front hits, usually the warm air rises.
The temperature decreases.
Precipitation, usually in the form of rain, is a common reaction of a cold front when it meets a hot environment.
When a warm front moves into a cold front, the warm air gradually rises over the denser cold air. This can lead to the formation of clouds and precipitation. The warm air displaces the cold air, leading to a gradual increase in temperature and humidity.
A front is an area of unsettled weather. In front of a cold front is warmer air. Behind a cold front is colder air. As the colder air meets the warmer air, the cold air rides over the warmer air and causes condensation. Rain happens. Since conditions are unsettled, winds blow. The warm air fights back. Sometimes tornadoes form. The cold front either wins and goes forward or collapses.
At a cold front, warm air is forced up and over the cold air mass. This usually results in rain and possibly thunderstorms, which may be severe.
An "occlusion" forms.
When a cold front overtakes a warm front, it forms an occluded front. This happens when the cold air mass catches up and lifts the warm air mass off the ground. An occluded front typically brings a mix of weather conditions, such as precipitation and strong winds.
It pretty much sits still as the Warm Front passes 'overhead'. It will get pushed back/up a bit.