[Weather] November snow for the first time in 117 years...Up to 20cm more tonight.

[Anchor]
Over 20cm of heavy snow fell in the central part of the country, including Seoul, overnight, and heavy snow warnings were issued everywhere.

Seoul also recorded heavy snow in November for the first time in 117 years.

There are some places where snow has weakened for a while now, but up to 20cm more snow is expected in the central interior by tomorrow.

We will find out the cause of the heavy snow and the weather forecast in the future with the reporter.

Kim Min-kyung is in the YTN weather and disaster reporter studio.

Let's start by looking at it overnight, it was the first snow and it was literally heavy snow.

How much snow did it fall?

[Reporter]
Yes, it was tremendous.

Overnight, 22cm poured into Yongmunsan Mountain in Yangpyeong, Gyeonggi-do, and 21.7cm poured into the big screen of Pyeongchang, Gangwon-do.

In Seoul, more than 20cm of snow was recorded in various parts of the central region, including 20.6cm in Seongbuk-gu and 20.4cm in Gangbuk-gu.

16.5cm of snow also accumulated at a weather station in Songwol-dong, Jongno, which is used as an official observation value in Seoul.

In the meantime, 12.4cm, which was poured out on November 28, 1972, was the number one in history based on Seoul,
As
broke records, it recorded the highest snowfall in November since weather observations began in 1907.

[Anchor]
What about now?

[Reporter]
Yes, let's look at the radar image that shows the movement of snow clouds.

The main rain cloud band, which affected it until dawn, falls east in the morning

So rain clouds are flowing in from the west again.

The area where the deep purple is painted with a heavy snow warning is under heavy snow warning,

Even now, heavy snow warnings are in place across the southeastern part of Seoul,
Heavy snow warning for parts of southern Gyeonggi Province and eastern North Jeolla Province
Snow warnings continue to be issued in the Seoul metropolitan area, Gangwon, Chungcheong, Honam, Yeongnam, and Jeju mountains.

[Anchor]
Cold air is the cause of the heavy snow?

[Reporter]
Yes, but it's not usually cold air.

Shall we read the diary?

It's about 5km above the top,
This red mass above the Korean Peninsula, so this is the upper cold air vortex.

The video I prepared is going out together.

Simply put, you've seen the water fall into the shape of a whirlwind when you take out the water plug after receiving it in the bathtub.

Like water draining from a bathtub, cold air whirls down from the upper atmosphere to the ground in the form of a funnel like an ice cream cone.

So, cold air comes down from the north, and cold air comes down from the upper and upper floors, so it's double affected

The intensity of the cold is stronger than the sparkling cold last week.

Snow was also a problem, because the air on the upper floor is colder than the air on the ground, and the heavier the air, the heavier it becomes.

So, as the cold air comes down, it digs under the air that was originally on the ground, and the atmosphere becomes unstable, resulting in a small-scale low pressure.

The clouds made here became snow clouds, not rain clouds, because the temperature was so low.

[Anchor]
On top of that, the increased sea temperature due to warming also had a big impact?

[Reporter]
Yes, in general, when heavy snow falls in winter, one of the patterns is when the cold northwest wind blows.

In winter, the water temperature of the sea is warmer than the air temperature.

Clouds develop as the cold wind passes through the relatively warm West Sea.

Recently, the temperature of the sea around the Korean Peninsula has risen by 1.5 degrees in the past 100 years, which is 2.5 times higher than the global average.

As a result, the temperature difference between the atmospheric temperature and seawater temperature widens, resulting in stronger cloud development.

[Anchor]
But there's one more crisis tonight?

[Reporter]
That's right.

Do you want to read your diary again?

It's a 5km situation on the top floor.

As this low pressure turns counterclockwise, strong snow clouds are coming in once again between tonight and tomorrow morning, this time to the central and southern parts of the country.

This depression is called a pressure trough.

The clouds are developing well here,

Originally, the low pressure moves counterclockwise from the west to the east, so it has to be affected once and then moved to the east,

The upper atmosphere flow is stagnant right now.

As the low pressure continues to spin like a cog in place, the trough of atmospheric pressure affects our country, and this point is considered to be tonight.

Because of this, more than 20cm of snow is expected to fall in the mountains and metropolitan area of Gangwon-do and 15cm in Chungcheong and Honam by tomorrow.

[Anchor]
But Jungbu is also a problem, but we have to be especially vigilant in Chungcheong inland?

[Reporter]
That's right.
As I mentioned earlier, the cold northwest wind passes through the West Sea, and snow clouds develop and snow falls on the West Coast, especially in the West Coast area,
The
problem sometimes causes sudden heavy snow in Daejeon, Asan, Cheonan, and Cheongju, which are downtown areas of Chungcheong.

It's called the "Asan Bay Effect."

I'll explain it to you while looking at the screen.

Clouds do not pass through the far west sea,

When the wind direction is 300 degrees or higher, clouds pass through Gyeonggi Bay, Asan Bay, and enter Chungcheong inland.

The problem is that the width of the cloud is very narrow, like a rain cloud in the shape of a rainy season, making it very difficult for supercomputers to predict.

Around December 30, 2020, snow accumulated in an instant of about 10cm in a short period of three hours in some parts of Sejong.

[Anchor]
It was the first snow slower than last year, but it was a heavy snow from the beginning. Is there a standard for heavy snow?

[Reporter]
That's right.

The first snow standard in Seoul is that the first snow is when snow is observed at a weather station in Songwol-dong, Jongno.

This year, it was later than last year and six days later than the average year.

But as you said, it's been a heavy snow since the beginning,
The
snow is based on a special report.

It is classified as a heavy snow warning when the newly fallen snow is more than 5cm for 24 hours, and a heavy snow warning when it is more than 20cm, but the standard is higher in mountainous areas, so a heavy snow warning is issued when it is more than 30cm.

[Anchor]
I heard it's heavy snow this time. What's the difference?

[Reporter]
"Heavy snow" is snow that has a lot of moisture as clouds pass over the sea, and it's called "humid snow."

It clumps well because there is a lot of moisture.

On the contrary, dry and dry eyes are called 'construction'.

This construction and wet snow differ greatly in weight even if the same amount of snow falls.


If 1m of snow accumulates in a 1m long space,
The difference is twice as light as
with light snow, 150kg for construction, and 300kg for heavy wet snow.

In particular, when 50cm of wet snow accumulates in a typical greenhouse, the weight rises up to 30 tons,

There are two 15-ton trucks and 30 power poles.

[Anchor]
This snow, how long will it fall?

[Reporter]
Yes, it is expected to overcome the crisis once from tonight to tomorrow morning, and stop after a lull everywhere from tomorrow afternoon.

However, snow clouds are expected to follow even after the barometric pressure trough, so southern Gyeonggi Province is expected to continue until late tomorrow night, and Chungcheong, Honam, and Jeju Island are expected to continue until the day after tomorrow.

[Anchor]
The wind was too strong, and there was a typhoon-like gust, right?

[Reporter]
That's right.

At one point in the early morning, typhoon-like gusts of more than 30 meters per second hit Ansan, Gyeonggi Province, and Taean, Chungcheongnam-do.

Strong wind warnings were issued not only on the coast but also on some inland areas.

Strong winds are also caused by the cold air on the upper floor.

I'll look at the diary again.

This time, it's a ground weather map.

The narrower the gap between these black lines, the stronger the wind,

The Korean Peninsula is quite tighter than the rest of the world.

The wind becomes stronger between high and low pressure,

The cold air here is heavy, so the wind became stronger by strengthening the slope as it dug in.

[Anchor]
Snow is snow, but it's definitely colder than yesterday.

Seoul recorded the lowest temperature?

[Reporter]
This is because, as I mentioned earlier, the double cold air came down from the north and upper floors.

The lowest temperature in Seoul this morning was minus 1.3 degrees, the lowest this fall.

The wind was strong, so the wind chill dropped to minus 4.2 degrees Celsius.

Not only Seoul but also most of the central region recorded below zero.

[Anchor]
What are the prospects for the cold?

[Reporter]
The temperature drops further tomorrow and the day after tomorrow.

In Seoul, the cold will peak at minus 2 degrees tomorrow and minus 4 degrees the day after tomorrow, which is Friday.

Next week, when winter begins, the lowest temperature is expected to continue between 1 degree Celsius and 2 degrees Celsius in Seoul, and below-zero cold in most inland areas.

[Anchor]
By the way, the Korea Meteorological Administration predicted that this winter's forecast would be colder than usual, but changed it to 180 degrees and predicted that the temperature would be similar to or higher than usual, but it's too cold even before the start.

[Reporter]
That's right.

In fact, the Korea Meteorological Administration expected the extreme cold to appear at the end of last month and in December.

Have you heard of the paradox of warming?

This is because the earth warms up due to warming, but it gets colder in winter in Korea.

Around the Arctic, a very fast wind called 'jet airflow' that traps the cold air of the Arctic continues to blow.

If you pull the rubber band tight and apply weak force, it will loosen and droop.

This is because as this wind weakens due to warming, the coldness of the trapped Arctic descends to our country.

However, the reason why the Korea Meteorological Administration revised its forecast in a month is the seawater temperature.

As mentioned earlier, the sea temperature around the Korean Peninsula is 1.8 degrees higher than usual, and it has risen 1.5 degrees in 100 years at the longest.

This is because when the sea temperature is high, the heat in the sea is released, and high pressure develops around the Korean Peninsula, and the temperature rises.

However, just because this winter is similar to or higher than the average year does not mean that the cold air is weak.

It's similar compared to the average winter. Like this time, and in the middle of winter, there will be quite a few days when the cold air temporarily falls stronger than this time.