When does winter start to get colder and when does it get cold?

Autumn usually starts to get colder after September. But it depends on the region. In the north, the temperature usually drops after the beginning of autumn, and at the latest in September, but in the south.

It will probably be in November.

There is a saying that "the cool breeze arrives on the 3rd day of the beginning of autumn", but after the beginning of autumn, most areas are still dominated by sunny and cloudy weather, the rainy weather is not obvious, the temperature can still reach 31-33, the average daily temperature is still on the high side, and the weather is still "sultry".

In Guangdong, the weather generally begins to cool after the National Day.

By November, you will definitely want to wear long-sleeved clothes.

I remember that November in 09 was a bit special, there was a cold air, not ordinary cold.

It will get cold in winter, so if you don't have air conditioning, pay attention to adding quilts in time.

The weather gets cold in winter, in October in northeast China, and not in southern China.

The general rule of thumb is:

After the first cold wind passes through in autumn.

That is, after the first significant cooling.

It won't be very hot anymore.

It depends on the place.

In the south, it is generally around mid-October.

In the north, it is generally around the end of September and the beginning of October.

It's cold in mid-October and November, and it's probably going to snow, and last year it snowed early.

Today has already begun, tomorrow the temperature will drop a little, the day after tomorrow will be lower, and the cold winter has come.

The first reason: global warming.

We all know that the coldest time of winter is not when it snows, but when it melts, because when the ice and snow melt, it absorbs a lot of heat, and the surrounding temperature drops. Due to severe global warming, this year's Arctic sea ice is the second-lowest on record, a large number of glaciers have melted, and a powerful blast of cold air has formed over the Arctic.

In the past, when the polar vortex was strong, the cold air was wrapped in the North Pole by the vortex, and the cold air could not go south on a large scale, and that winter would be a warm winter.

But this year, the polar vortex weakened (the reason is not much that few people want to see), and it failed to encapsulate the cold air in the Arctic, which was formed by the melting of glaciers, and generally speaking, the polar vortex went south in three directions: North America, Europe, and Siberia.

This time in 2021, it happened to come out of the mouth of Siberia, and because Siberia is land, it does not have the ability to control temperature like the ocean, so the north of my country is the first to bear the brunt and directly feel the temperature of the Arctic when it freezes.

The second reason: La Niña events in the equatorial eastern Pacific Ocean are currently at their peak.

You can understand La Niña as the opposite of El Niño, and last year's continuation to this day is perhaps the strongest in the first 20 years of the 21st century.

Judging from the historical experience of our country from 1954 to the present, there is an 80% probability that our climate will be colder and drier in winter, especially in the south. The 2008 snow disaster was also affected by the La Niña event.

The reason why this year's winter is so cold is not due to one reason, global warming, extreme weather, ...... luckAll of them have played an important role in this.

No, it won't

The beginning of winter is the nineteenth solar term of the year and the first solar term of winter. However, the beginning of winter does not necessarily mean the arrival of winter. In meteorology, when the average daily temperature falls below 10 for five consecutive days, the first day of these five days is used as the standard for the start of winter.

According to this criterion, most of the northern part of the country is already in winter before the beginning of winter, while many parts of the south are still in autumn, and the real winter will come in about 20 days. After the beginning of winter, cold air activities gradually become more frequent, and the temperature decline trend accelerates. The cold air will bring significant cooling, strong winds and even rain and snow, and the first snow often falls in some parts of North China at this time; When strong cold air comes, snow even falls in the Gangnam area.

It is said that 39 days are the coldest.

As a method of keeping time for the cold winter, the 81 days after the winter solstice are divided into 9 stages, and each stage is 9 days, which is called "winter ninety-nine", which is often said to count nine cold days. Among them, the 19th to 27th days after the winter solstice every year are called "Sanjiu".

In a year, the day of the winter solstice is the shortest, the angle between the sun's rays and the ground is the smallest, and the ground gets the least solar heat. Why is that?

Meteorological experts say that the temperature on the ground is not only affected by the intensity of the sun's rays, but also related to the heat dissipation on the ground. Because after the summer solstice, the day is long and the night is short, the angle between the sun's rays and the ground is larger, the ground gets the most heat, and the heat dissipation at night is less, so that the heat storage of the ground gradually increases, to the winter solstice, although the sun irradiation time is shorter, the angle between the sun's rays and the ground is the smallest, but the heat stored by the ground in summer and autumn can also be supplemented, so the weather is not necessarily very cold.

In the "39", because the ground receives less solar heat, the heat dissipation at night exceeds the heat absorbed during the day, and the heat stored on the ground has been exhausted at this time, and the ground temperature gradually drops due to the heat that cannot make ends meet, and the weather is getting colder and colder. At this time, if there is the influence of cold air, the weather becomes very cold. Therefore, the weather in "Sanjiu" is the coldest.

December 21 or 22 is the winter solstice solar term, which means that it has entered winter and is starting to be a little cold.

January 5th is a small cold, and the coldest time comes.

January 20 was a big cold and continued to be cold.

There are a total of 81 days in winter, and the coldest time is Sanjiu, which starts on January 8 or 9 after Xiaohan, and those 9 days are the coldest time of the year. Ninety-nine days in the winter solstice solar terms when the arrival of the beginning of the calculation, the day is called nine, nine days after the call two-nine, a total of nine nine 81 days, the solar calendar March 3 ninety-nine end.

As the saying goes: the heat is in the middle, and the cold is in the three-nine. The 24 solar terms are not determined according to the solar calendar or the lunar calendar, but the stem calendar, also known as the star calendar, the Jiazi calendar, etc., is an ancient calendar that marks the year, month and day with 60 different sets of heavenly and terrestrial branches.

According to the U.S. Oceanic and Atmospheric Administration (NOAA), recent observations in the El Niño critical region of the Eastern Pacific Ocean have shown that the surface sea surface temperature (SST) is higher than the long-term average, and has reached the El Niño threshold (the surface SST is not lower than the degree).

But while it is true that the threshold for El Niño is higher than the mean SST, it must persist for months and elicit an atmospheric response for an El Niño to occur. This is because sea surface temperatures are susceptible to variability in the short term and are influenced by weather and seasonal climate patterns (e.g., intratropical seasons**).

Long-term observations of El Niño show that the presence of El Niño tends to cause the south to be wetter (dark green) in winter and spring, and the southern region is more likely to be warm (orange). But at present, the current changes in the Pacific Ocean are only short-term fluctuations, and the long-term may still be neutral, so it is not easy to judge whether the state of China's winter this year is a cold winter or a warm winter, and the climate pattern has been very abnormal since the beginning of 2019, and the weather conditions in China may be more extreme this winter.

However, due to the influence of the El Niño phenomenon, the wind speed in the north is low this autumn and winter, the temperature is high, the cold air activity is low, and the intensity is weak, and the haze may last for a long time and cover a wide area.

Last year we were affected by La Niña.

Not necessarily. In previous years, La Niña will lead to a colder climate, but in the context of global warming, the factors affecting China's winter climate are more complex, in addition to the impact of La Niña events from the equatorial eastern Pacific Ocean, it will also be affected by factors such as Arctic sea ice melt and Eurasian snow cover changes. Whether it is cold or not, you need to pay attention to the weather conditions in real time.

According to the perennial situation, La Niña, like El Niño, will disrupt the global climate, but the impact is the opposite of El Niño, La Niña phenomenon is easy to cause China's winter climate to be cold, prone to cold winter.

It is uncertain whether there will be a cold winter in 2021, as the temperature is still changing steadily.

Hello, this year's winter actually feels similar to usual, and I feel that it is not particularly cold so far, and the temperature is basically the same every year, so it will not be particularly cold.

Although the temperature is about the same, you must also pay attention to keeping warm to avoid colds, because in this situation, it is especially inconvenient to catch a cold. In the past, it was a small problem, but now if you have a cold, it is like a big problem, and you have to go to the hospital for various tests.

Of course it's going to be cold this winter! I'm a handsome little guy