What are the characteristics of cold front crossing?

1, before the cold front crosses the border:

Sunny, low pressure;

2. When a cold front crosses the border:

The air pressure in front of the front drops sharply, and the air pressure behind the front rises. The temperature drops; Gradient increase; Atmospheric baroclinic pressure increases; The wind direction changes clockwise; There is precipitation, even thunderstorms.

This situation generally only occurs in mid-latitude areas, and it is also possible in low-latitude areas in late spring and early summer, because the cold front at that time generally develops at the latitude of 25-30, while the temperature in low-latitude areas is generally high, and lightning is prone to occur in the case of high-temperature friction.

3. After the cold front crosses the border:

Cooling is controlled by cold air mass; The air pressure drops first and then rises; There must be rain before the front; The weather is clearing up.

Extended data:

The weather conditions of the cold front can be roughly divided into two types:?

1, the cold front moves slowly and has a small slope. It is in front of the 700hpa trough in the air and is usually called the first type cold front. This type of cold front, because the cold air mass moves forward on the one hand, makes the warm air mass in front of the front move forward on the one hand, and is forced to slide upward along the front on the other hand. When the water vapor condition is sufficient, cloud system and precipitation will be generated on the front.

2. The cold front moves quickly and has a large slope, which is often called the second type cold front behind the 700hpa trough or near the high altitude trough line. The cold advection above this cold front is strong and the airflow sinks. Only the warm air near the ground front is lifted, but the front has a large slope and a strong airflow moves upward.