How is the cold vortex generated over the Northeast?

The "Northeast" in the Northeast Cold Vortex refers to its location: 40 to 50 degrees north latitude and 110 to 125 degrees east longitude; "cold" refers to the elements that exist in the middle and upper troposphere (about 5,000 meters above the ground) ) is a cold air column, which is a cold closed low-pressure circulation system; "vortex" refers to the low vortex formed by counterclockwise rotation.

The temperature in the center of the Northeast Cold Vortex is significantly lower than that of the surrounding areas, and as it moves, it "throws out" streams of cold air. When it meets the local warm and humid air flow, it will produce short-term heavy precipitation, thunderstorms, strong winds, Hail, and even weather changes such as sudden drops in temperature and daytime turning into night.

The Northeast Cold Vortex is like a huge columnar electric fan.

On July 2, 2021, the Keyou Middle Banner of Xing'an League in Inner Mongolia Autonomous Region was hit by a tornado, which was related to the cold air "thrown out" by the Northeast Cold Vortex System. In the first half of 2021, many strong winds in North China and rainfall from June to July are also the "presence" of the Northeast Cold Vortex.

Are you a "slow person" who still likes to "fight"?

The Northeast Cold Vortex can be seen all year round and is most active in summer. On average, more than eight Northeastern cold vortices visit China every summer, affecting nearly 40 days. It can be said that the Northeast summer is incomplete without the Northeast Cold Vortex.

Statistics show that in Northeast China, the Northeast Cold Vortex causes the most thunderstorms. In addition, 64% of squall lines (a type of strong convective weather) are also related to it.

As can be seen from the figure, the Northeast Cold Vortex is visible all year round and is most active in summer. This is because the "predecessor" of the Northeast Cold Vortex is a large group of deep cold air. After it rotates and "breaks into" the territory of warm air, it is "surrounded" by the warm air, and the Northeast Cold Vortex is formed.

The Northeast Cold Vortex is not only "naughty", but also "irritating". It is a "chronic person". When it appears, it is like a giant umbrella, covering a certain area for as short as three to five days, and as long as it can "stay" for more than ten days. For example, in June 2012, the Northeast Cold Vortex occupied Northeast China for 21 consecutive days.

Although the Northeast Cold Vortex was "born" in the Northeast, its impact is by no means limited to the Northeast. It is huge and is an important source of cold air in summer. In addition to being "naughty", he also likes to "fight" with other weather conditions.

For example, in 2013, the Northeast Cold Vortex had a serious "conflict" with the Mongolian cyclone and the subtropical high, causing frequent heavy rains in Jilin Province for consecutive days.

The precipitation during the Meiyu period and the pre-flood season in South China is also closely related to the "naughty bag" of the Northeast Cold Vortex - in years when the Northeast Cold Vortex is strong, it can "guide" the cold air from the north to invade southward, and interact with the warm Moist air flows "fight" in the Meiyu area, resulting in more Meiyu rainfall, while in years with weak cold vortex in the Northeast, there is less Meiyu rainfall.

Is the Northeast Cold Vortex a "bad boy"?

The Northeast Cold Vortex has brought so many disasters, so is it a "bad boy"? Of course not! The rainfall it brings can nourish the land, and its variability can make the sky as blue as the sea.

For example, every year in mid-May, after crops are sown in the Northeast, June is the water-demanding season. The Northeast Cold Vortex can bring abundant precipitation, which is beneficial to the growth and development of crops.

The continuous rainfall brought by the Northeast Cold Vortex can also "wash" inhalable particles in the air and purify the air.

Although the Northeast Cold Vortex is sometimes "naughty" and occasionally "fights and causes trouble", we cannot deny that it is a very important weather system. The Northeast Cold Vortex and the weather phenomena it causes have always been a matter of concern and research among meteorological science and technology workers.