“Dangerous Typhoon” What I saw from the Japan Meteorological Agency Conference ... | NHK News

“Dangerous Typhoon” What I saw from the Japan Meteorological Agency Interview… October 11 21:00

A large and very strong typhoon No.19. The possibility of landing on the Tokai region or Kanto region on the 12th has increased. If it landed with the current power, it will be the first time in observation history in eastern Japan.
The Japan Meteorological Agency called for “comparable to it” by referring to a typhoon 61 years ago with more than 1,200 victims.
This typhoon No.19.
What is the “dangerous situation” pointed out by the Japan Meteorological Agency?
I read the typhoon and the warning points from the press conference.
(Social reporter Yuta Okubo network reporter Akihiko Kanno Naoya Saito)

Special heavy rain warning in Kanto and Tokai?

“It is expected to be a record heavy rain over a wide area, and depending on the situation, a special heavy rain warning may be announced.”

At the beginning of the meeting from 11:00 am on the 11th, Koji Sugawara, Director of the Meteorological Agency, said, calling for the greatest alert.

If a heavy rain warning is issued in the Kanto region, it was announced in Tochigi and Ibaraki prefectures in the 2015 Kanto / Tohoku heavy rains.

The Japan Meteorological Agency cannot know the impact and impact of the word “special warning”. In previous interviews, there was a possibility of being touched by questions, but it is unusual to mention it from the “head” of the interview itself.

An executive said, “I have been in the Japan Meteorological Agency for many years, but I have never seen such a typhoon approaching Kanto.”

The reporter (Okubo) in the conference room felt the intention of the Japan Meteorological Agency to convey the sense of crisis about the typhoon.

“Over 1200 victims, comparable to the Kanogawa Typhoon”

"From 12th to 13th, a very developed rain cloud due to typhoons is applied in a wide range from western Japan to the Tohoku region, so it is very heavy rain and intense rain, and it is comparable to" Kanogawa Typhoon "in the center of eastern Japan It could be a record heavy rain. ''

Mr. Sugawara mentioned the “Kanogawa Typhoon” 61 years ago when he talked about the outlook for heavy rain.

In September 1958, he approached Shizuoka Prefecture and landed on the Miura Peninsula in Kanagawa Prefecture.

In addition to the “Kano River” flowing through the Izu Peninsula due to heavy rains caused by typhoons, flooding and sediment disasters were repeated in various places.
The total number of victims exceeded 1200.
It is a typhoon that has been carved with a strong memory among older people.

In this typhoon, it continued to rain and became a record heavy rain, and total rainfall reached 750 mm in the central Izu Peninsula.

Also, the amount of rain that falls on a day is 419.2 mm in Izu Oshima, and 371.9 mm in the center of Tokyo.
▽ 288.7mm in Chichibu, Saitama ▽ 287.2mm in Yokohama.

The most rainfall in the history of observation in Tokyo and Yokohama has not been updated since then.

In this typhoon, it is expected that rain will continue for a long time, mainly on the Pacific side of eastern Japan, before approaching.

Rain forecasts may change, and there are differences in the amount of rainfall that increases the risk of sediment-related disasters and floods depending on the region, but there is a possibility that the rainfall will reach several months of the normal year.

If it rains so much, the risk of flooding increases even in large rivers, and there is a risk of landslide disasters.

In order to make people aware of such dangers, the company said that it was a reference to the “Kanogawa Typhoon”.

The dangers of storms and storm surges

“From 12th to 13th, there are places where violent winds blow in a wide range in western Japan, eastern Japan, and the Tohoku region, resulting in record storms.”

At the interview, not only heavy rain, but also wind, waves and storm surges were repeatedly called for vigilance.

As for the forecast on the evening of the 11th, the maximum wind speed on the 12th is 45 meters in Tokai and 40 meters in Kanto Koshin. It is difficult to drive a car, and it seems that the running truck rolls over, so outdoor activities are extremely dangerous.

Furthermore, the maximum instantaneous wind speed is expected to be 60 meters for both Tokai and Kanto Koshin.
The maximum instantaneous wind speed observed in Chiba City at the time of Typhoon No. 15 last month was 57.5 meters.
Last year, 58.1 meters was observed at the time of Typhoon No. 21 when a tanker that was swept away by a strong wind at Kansai Airport collided with a connecting bridge. There is a possibility that a comparable wind may blow.

On the coasts of the Tokai, Kanto, and Izu Islands, it is expected that the wave will continue to be violent with a wave height of 13 meters.

Furthermore, storm surge.
The pressure near the center of the typhoon is low, and the sea level is sucked up and rises more than usual. It is now a time of high tide, and high tides may occur if the high tide time overlaps with the approach and passage of a typhoon.

In addition, if a very strong southerly wind blows, seawater may be blown and the sea level may rise further. Unlike the high waves, the whole sea surface rises, so it is very dangerous near the coast.

May cause long rain at the “coastal front”

Typhoon No. 19 is going to hit the metropolitan area where many people live.

During the interview, it was pointed out that not only the slopes on the southeast side of the mountain, where rainfall is likely to be high, but also heavy rainfall on the plains.

The cause is the “coastal front”, which is difficult to appear in the weather map because it is local.

Even during the Kano River Typhoon, there was a possibility of heavy rain due to this “coastal front”.

This time, too, it is raining for a long time on the flat area in the Tokyo metropolitan area, and there is a risk that it will become a record amount of rainfall, so caution is required.

“The morning temperature above Honshu is getting cold, and there is a situation where cold air is accumulated in the lower layer of the atmosphere, and the front line between the wet warm southeast wind and the cold air layer on land is very It is assumed that it will become clear, and such fronts may be stagnant, and there is a risk that the total rainfall will be very large near that front. ''

Be careful not only on the east side but also on the northwest side

Although this typhoon No. 19, the influence is unavoidable mainly in the Kanto and Tokai areas, caution is also required on the Sea of ​​Japan side. The reason is “Aki Typhoon” and “High Pressure”.

`` This typhoon is a so-called autumn typhoon, and high pressures bulge out from the continent to the Sea of ​​Japan, so even in the northwest where the typhoon is not in danger, it is between this high and the typhoon. The slope of the air pressure becomes steep, and storms or strong winds blow in a wide range on the north or west side of the typhoon, and there is a possibility that the total rainfall will increase from Hokuriku to the San'in region due to the blowing of wet northeast wind and north wind. I'm assuming the situation. "

It is known that typhoons that blow in a counterclockwise direction generally have stronger wind and rain on the east side because their course and wind direction overlap.

However, in the future, it is expected that a mobile high pressure will appear from the continent to the Sea of ​​Japan.

The pressure gradient between the high pressure and the typhoon going north (the inclination of the pressure, the stronger the wind, the stronger the wind) becomes steep.

On the Sea of ​​Japan side, wet winds blow toward the north, so it rains and moist air continues to flow in after the typhoon goes off Sanriku.

There is a risk that the total rainfall will increase, so caution is required.

Appreciable heavy rain and storm

“We want to make it our first priority to escape difficulties and ensure safety without going out unnecessarily.”

During the interview, Manager Sugawara called on to repeatedly take actions to save lives.

Of particular concern are Chiba Prefecture and the Izu Islands, which have just been severely damaged by Typhoon No.15 last month. In Chiba, more than 35,000 homes were damaged. There are still many houses with seats on the roof, and recovery has not progressed sufficiently.

“In the disaster area of ​​Typhoon No. 15, there are still a lot of houses in the blue sheet state. In such a case, this typhoon will surely cause a considerable storm due to heavy rain. Staying inside can be dangerous, either by using the shelter set up by the local municipalities, or by evacuating to a relative at an early stage. I want you to take it. "