Weather process with or without warm front in winter

warm front

In the process of front movement, if warm air plays a leading role, it will push the front to move to one side of the cold air mass. This front is called a warm front. After the warm front crossed the border, the warm air mass occupied the position of the original cold air mass. Warm fronts are mostly active in northeast China and the middle and lower reaches of the Yangtze River, and are often accompanied by cold fronts. When the warm front crosses the border, it is warm and humid, the temperature rises, the pressure drops, and the weather turns cloudy and rainy. Not a cold front. The warm front moves slower than the cold front, which may cause continuous precipitation or fog.

Warm front weather patterns

In the cold air mass under the warm front, stratocumulus and cumulus are often produced under the action of airflow convergence and turbulence because of the humidity of the air. If the raindrops falling from the front warm air evaporate in the cold air mass, the water vapor content in the cold air mass will increase, and when it reaches saturation, cumulus clouds and stratocumulus clouds will be produced. If this saturated condensation occurs in the ground layer near the front line, frontal fog will be formed. The above is the general situation of warm front weather, but when the warm air is unstable in summer, there may be showers such as cumulonimbus clouds and thunderstorms. When the water vapor content in the warm air mass is very low in spring, only some high clouds appear and there is little precipitation.

There are few obvious warm fronts in China, and most of them are accompanied by cyclones. In spring and autumn, it generally appears in the Jianghuai Basin and Northeast China, and it mostly appears in the Yellow River Basin in summer.

Warm front weather characteristics

Before crossing the border: controlled by a single cold air mass, the temperature is low, the air pressure is high and the temperature is sunny.

When crossing the border: rainy, mostly continuous rainfall (precipitation is concentrated in front of the front)

After crossing the border: the heated air mass is controlled, the temperature rises, the air pressure drops, and the weather turns fine.

Characteristics of warm front precipitation

Low intensity, wide range and long time often appear in temperate zone. Warm front precipitation is ahead of the front.

South China: Spring is warm and sunny, and spring is cold and rainy.