About Typhoon No.19 Meteorological Agency, Koji Sugawara, Director of the Forecast Division, interviewed (full text) | NHK News

About Typhoon No. 19 Meteorological Agency, Koji Sugawara, Director of the Forecasting Department, interviewed (full text) October 11, 19:01

On Typhoon No. 19, the Japan Meteorological Agency held a press conference from 11:00 am on the 11th, and recorded a heavy rain comparable to the Kanogawa Typhoon, which killed more than 1200 people in Shizuoka and Kanto, and announced a special warning of heavy rain He called for strict vigilance as there was a possibility of doing so.

The contents of the interview are as follows.

A large typhoon No. 19 goes north over Japan's South Sea with a very strong force.
Typhoon keeps very strong power. The possibility of landing in the Tokai or Kanto region on Saturday the 12th has increased.
In addition to storms and high waves, there is a risk of record heavy rain, especially in the Kanto region.

“Overview of Typhoon 19”

The large and very strong typhoon No. 19 is expected to land in the Tokai region or Kanto region from the evening to the evening on the 12th and stay in the Tokai region or Kanto region.
From the 12th to the 13th, a violent wind blows in a wide range from western Japan to the Tohoku region, mainly in eastern Japan.
In addition, the highly developed rain cloud of the typhoon itself will cause a record heavy rain over a wide area.
Depending on the situation, a heavy rain special warning may be announced.
In addition to Izu, landslide disasters occur frequently in the Kanto region, and there is a risk that it will be a record heavy rain comparable to the Kanogawa Typhoon in 1958, due to flooding of rivers.
Strictly alert nationwide to storms, high waves with swells, landslides caused by heavy rain, inundation of low land and underground facilities, flooding and flooding of rivers, inundation due to waves that overlap storm surges and storm surges, and damage to coastal facilities Please give me.
Also, pay close attention to intense gusts such as lightning and tornadoes, and pay attention to traffic obstruction, crop management, power outages, and salt damage.
Pay attention to weather information such as warning warnings announced by meteorological stations in various places, and in order to protect your life and the lives of important people, before the wind and rain become stronger, before darkening at night, according to evacuation recommendations of municipalities, etc. Please evacuate early and ensure safety.

“Course forecast”

Although it is the latest course forecast of a typhoon, the typhoon is currently moving north over the southern seas of Japan while maintaining a very strong power.
After that, the possibility of landing in the Tokai region or Kanto region from the evening to the evening on the 12th is increasing while maintaining a very strong power.
After that, it is expected that the speed will increase from eastern Japan to the Tokai and Tohoku regions, moving northeast, and changing to a temperate cyclone on the southeastern sea of ​​Hokkaido.

“Storms and high waves”

The outlook for storms and high waves.
On the Pacific side of eastern Japan and western Japan, it is expected that there will be a big storm from the afternoon on the 11th, a very strong wind from the evening on the 11th, and a fierce storm by the night of the 11th.
From the 12th to the 13th, there will be places where a violent wind blows in a wide range of western Japan, eastern Japan, and the Tohoku region, resulting in a record storm.
On the Pacific side, fierce damage continues.
In addition, it is expected that a storm will blow on the Sea of ​​Japan side as well.
There is also the risk of a storm similar to the previous Typhoon No. 15, and since the typhoon is large, it is expected to be a storm in a wider range including the Sea of ​​Japan than No. 15.
The maximum wind speed and the maximum instantaneous wind speed that are expected in each region are 45 m maximum wind speed and 60 m maximum wind speed in the Tokai region. In the Kanto Koshin region, the maximum wind speed is 40 meters and the maximum instantaneous wind speed is 60 meters.
In terms of waves, the height of the waves is 13 meters in the Tokai, Kanto, and Izu Islands.
If the height of the wave exceeds 9 meters, it is expressed as a fierce loss, but we expect a 13-meter high wave far above that. This is a very dangerous situation.

"heavy rain"

Next is the prospect of heavy rain.
From the afternoon of the 11th, extremely heavy rain begins to rain on the Pacific side of western Japan and on the southeastern slope of eastern Japan.
From 12th to 13th, a very developed rain cloud due to a typhoon is applied in a wide range from western Japan to the Tohoku region, so extremely heavy rain and heavy rain fall, and it is a record equivalent to the Kanogawa typhoon in the center of eastern Japan There is a risk of heavy rain.
The 24 hour rainfall until 12:00 on the 12th is 500 mm in the Tokai region.
After that, the 24-hour rainfall until 12 o'clock on the 13th is 600 to 800 mm in the Tokai region.
In the Kanto Koshin region and the Hokuriku region, there is a risk of heavy rain in a wide range, such as 300 to 500 mm.

“Storm surge”

Warning is also required for storm surges.
October 14 is the full moon.
Because it is close to the time of the high tide, especially when the high tide time and the tide level deviation due to the influence of the typhoon overlap, the risk of storm surge disasters will be very high.
For example, Tokyo Bay is the high tide time of each place.
In Tokyo, the high tide time on the 12th is 16:31. 13th is 4:29 am.
So far, if the typhoon is going through the center of the forecast circle, it is not exactly the same as the high tide timing of the evening of the 12th day or the dawn of the 13th day, The possibility increases, and when a very strong south wind blows, it may be high tide or low tide, but it may cause tide level deviation enough to lift it, so strict caution is necessary is.

“Very strong power”

In the meteorological satellite cloud image, the latest meteorological satellite cloud image at 10:00 on the 11th, the typhoon eyes are still patched.
Compared to yesterday, the cloud top height around the center of this typhoon has become slightly lower, so the strength from the “furious” typhoon to the “very strong” level one level below It ’s down, but it ’s still very strong.
In the image, you can see that the shape of a round cloud with a very high degree of circularity is still present, and the eyes of the typhoon are patchy, maintaining a very strong power.
In addition, from the north of the typhoon, a very well-developed rain cloud spreads in the northwest direction, and a part of it has already begun to cover the Izu Islands, and the rain has begun to increase in the Izu Islands. The
After that, it is expected that heavy rain will continue on the 11th in the Izu Islands, and the rain foot will gradually become stronger.

“Front is stagnant”

Also, from the sea east of Japan to the vicinity of the Kanto region, the front line is stagnant, and a typhoon goes north to bite into this.
Furthermore, when the typhoon goes north, the wet southeast wind on the east side of the typhoon hits the front line. On the other hand, the north side of the front line is a cool mobile high pressure in the fall, and this front line becomes active and stagnates, and there is a possibility that the total rainfall will be very large near this front line.

“Rainy clouds”

Currently, the rain clouds associated with the Baiu front are in the vicinity of the Tohoku region, but a part of the highly developed rain clouds that spread from the north side of the typhoon to the northwest direction are beginning to be captured by radar.
Some of the developed rain clouds have already started on the Izu Islands, the southern part, and will gradually go north, so you need to be vigilant.

“Do you land in Tokai or Kanto?”

This is the expected course of the typhoon.
Currently 925 hectopascals, very strong forces, maximum wind speed of 50 meters.
After that, proceed north-northwest, change the course slightly northward, and go north at about 20 km / h at 9:00 am on the 12th. We expect 935 hectopascals at 9 o'clock on the 12th and a maximum wind speed of 45 meters near the center.
After that, if I keep going to the north with almost this power, and land in the Tokai or Kanto regions from the evening of the 12th to the night with a very strong power of 45 meters near the center at 945 or 950 hectopascals I'm watching
After that, proceeding east Japan or the Tohoku region with increasing speed to the northeast, off Sanriku at 9 o'clock on the 13th, and still seeing a typhoon at this point, I'm looking to change to low pressure.

Forecast weather map

It is an expected weather map.
Typhoon No. 19 is expected to land in the Tokai and Kanto regions while maintaining a very strong power.
The front line continues around the southern part of the Tohoku region, and heavy rains are expected in a wide area.
The typhoon is going north in a region where the sea surface temperature is very high, so it is assumed that it will come to Japan while maintaining a very strong power without weakening the power.

“Kanogawa Typhoon”

The “Kanogawa Typhoon” landed on September 26, 1958, illustrated at the beginning, but the Kano River was flooded, resulting in the death of 1000 people in the direction of Izu. Because of this, it is named “Kanogawa Typhoon”, but this typhoon also has a name in history that it brought record heavy rain to the whole Kanto region including the metropolitan area .
Tokyo's daily precipitation is 371.9 mm, which is still the top record of daily precipitation in Tokyo.
In addition, Chichibu and Kumagaya have a record heavy rain over a wide area, and there are situations where rivers have been flooded and flooded one after another.

“Extensive, not local”

The heavy rain caused by the typhoon this time is different from the type in which heavy rain falls locally, and the total rainfall increases due to extremely heavy rain or heavy rain in a very wide area.
For this reason, it is assumed that the average rainfall in the basin will be very large, and not only small and medium rivers, but also large rivers, there is a risk of flooding or flooding of rivers, so strict caution is required.

The following is a question and answer session.

“There is a risk of increasing total rainfall even on the north side”

Q.
Compared to the 10th, it seems that the size and size of the storm area has spread from east to west. I would like to know the dangerous situation caused by this.
The other point is that the rain region on the south now has a lot of rain, but if that is around the Kanto area, please tell me if you know where it will be.

A.
Although it is an area of ​​strong winds and storms due to typhoons, it is often said that typhoons are moving northward while maintaining a large state, and that normal typhoons are on the right side of the direction of travel, and that the danger semicircle requires special attention to storms. However, the typhoon this time is a so-called autumn typhoon, and a high pressure overhangs the north side of the typhoon, so if you look at the forecast weather map, the high pressure will be strong from the continent to the Sea of ​​Japan. Because it is overhanging, even on the northwest side, which is not a dangerous semicircle of this typhoon, the gradient of atmospheric pressure becomes steep between this high pressure and typhoon, so there is a storm or strong wind on the north side or west side of this typhoon It is assumed that there is a risk that the total rainfall will increase even from Hokuriku to the San'in region, etc. Cage you.

Relationship between rain and front in Kanto

Then, although it seems to be a rain cloud, a part of the north side has finally been seen by weather radar, and this will continue to move northward along with the north of the typhoon, so how much rain cloud is in what form Although it is difficult to take, it is basically assumed that it will be applied in the form of an arc in the form of Kanto to Tokai, or Kanto to Kinki, so Tokai and Kanto regions It is expected that there will be more rainfall.
Also, the morning air temperature above Honshu is quite cold, so there is a situation where cold air is accumulating in the lower layer of the atmosphere, and the front line between the damp warm southeast wind and the cold air layer on land Is expected to become very clear, and such fronts may be stagnant, and there is a risk that the total rainfall will be very high near the fronts, so caution is required.

“Beware of the front of the northern Izu Islands and the Boso Peninsula”

Q.
As an area where rain clouds are likely to continue in the same place, can we think of it as being slightly below the front or near the front?
If that happens, you can imagine that it will take the form of going around the edge of the Kanto area, but what about that?

A.
The front represented by the Far Eastern weather map scale is around the Tohoku region, but it is not necessarily blowing here, it is raining, the front between the cold land of the land and the southeast wind is a smaller scale Although we call it the coastal front, I don't know if that is around the Boso Peninsula or a little more north, but I'm rather wary of it being formed around the northern part of the Izu Islands and around the Boso Peninsula. It is a situation.

“The total rainfall in the Kanto region is quite heavy”

Q.
Interpreting that word, can it be read that rain in Kanto falls for quite a long time?

A.
The Izu Islands are already getting rainy, and after that, we expect heavy rain.
As for the Kanto region, heavy rain started to fall on some nights on the 11th night, and after that, it seemed that the rain feet would become stronger. By assuming that heavy rain will continue to fall on the night of the 12th, there is a risk that the total rainfall will be considerably increased.

“A record heavy rain even on flat ground”

Q.
Is it a plain or an upstream part of a river or both?

A.
It should be considered both.
In general, heavy rain due to the wet southeast wind blown by a typhoon is a pattern in which total precipitation increases mainly on the slope facing east or south due to the predominance of topographic precipitation, but I explained earlier. When the coastal front is formed near the Boso Peninsula, there is a possibility that very heavy rain and heavy rain will continue to fall in the vicinity, but I do not know the details, but I do not know the details, but Kanogawa Typhoon And it was raining 377 millimeters.
There is a possibility that it will be a record heavy rain not only in the mountains but also in the flat land including the Tokyo metropolitan area.

“Evasion is the top priority”

Q.
A level you shouldn't go out anymore?

A.
I agree. Looking at various reports, there are times when various transport operators are considering or planning things like planned suspension, and we often say that we should avoid going out unnecessarily. In fact, I would like you to secure safety by giving priority to escaping difficulties and not going out unnecessary.

What are the similarities with the Kano River?

Q.
The Kanogawa Typhoon is mentioned as an example, but has this been a similar phenomenon as a phenomenon that occurs? Is it okay to recognize that the area is slightly different?

A.
Although it is very risky to bring out similar typhoons, it is effective as an indication of the expected phenomenon or degree of disaster, but the location and extent of its occurrence varies greatly from case to case So there is no possibility of misleading.
This time, the Kanogawa Typhoon was brought about because the expected phenomenon or the degree of disaster was remarkable, so there was a point that the Kanogawa Typhoon was exemplified, and the course and power taken by the Kanogawa Typhoon, or There is a similar point in the speed of north.
Or we have decided that this should be used for explanation because of the high degree of similarity, including the size of the typhoon.

Call to preparation

Q.
You called for preparations by the 11th at the Wednesday interview.

A.
This time, a large and very powerful typhoon might hit directly during the three consecutive holidays, and it is also an autumn holiday season, so there are many people going out, so various institutions plan various events. I would like to inform everyone of the rough weather that is expected this weekend and make a necessary decision, so on Wednesday at a much earlier time than usual. This is the second press conference.
In that case, there are still 3 or 4 days before the typhoon approaches, so please be prepared for the 11th Friday, such as precautions for housing as shown by the Cabinet Office While quoting, I am urging to prepare.
By preparing for the 11th, there is no need to do anything anymore, but especially when the wind gets stronger, at that stage, if you go up on the roof, that kind of action will be dangerous. I would like you to pay close attention.
Once again, I would like you to re-inspect things like being prepared for the 11th.

What is the speed after landing?

Q.
Regarding the Kanogawa Typhoon, I think that the power dropped after landing at that time.
Even in the data of the maximum instantaneous wind speed, there is data that does not blow 30 meters in Tokyo, but if this typhoon also landed, would you drop the power, or might there be a lot of damage without dropping much? Is it yes?

A.
The Kanogawa Typhoon was also a fierce typhoon that observed the 870 mbar observatory at a time on the South Sea in Japan, but the power itself has suddenly weakened just before landing, and the record of wind such as the maximum wind speed Is not such a big deal.
Rather, it seems that the energy lost in this weakness was converted into rain, resulting in heavy rain. It is difficult to judge how much this typhoon is similar to this, but at least when predicting the power of Typhoon No. 19, the power will drop considerably when landing, but still maintained a relatively strong power I'm watching it as if I was going off Sanriku.

“Rain is long on the Sea of ​​Japan”

Q.
It means that very heavy rain will start on the 11th and it will be a heavy rain on the 12th. Is it necessary to be wary even after the rainy peak and typhoon have passed?

A.
The expected rainfall for 24 hours until 12:00 on the 12th is 250 mm in the Kanto Koshin region and the Izu Islands, and then the expected rainfall from 12:00 on the 12th to 12:00 on the 13th In many places, it is 600 to 800 mm in the Tokai region.
It is expected to be 300 to 500 mm in the Kanto Koshin region.
When it comes to the peak time zone of rain intensity, it also applies to the time zone where a very developed rain cloud surrounding the typhoon center is applicable. For example, in the Kanto Koshin region, it is night from noon on the 12th. The beginning of is the time when there is a possibility of heavy rain.

The typhoon this time is that it travels northeast from the eastern Japan to the Tohoku region at a high speed after landing, and then goes off the coast of Sanriku. However, on the Japan Sea side, it seems that there is a possibility that heavy rain will continue for a long time after the typhoon has moved off Sanriku due to the blowing of wet north wind on the Sea of ​​Japan side It is.

“Not a linear precipitation zone type”

Q.
There was a story about the coastal front, but can it be said that if these things stagnate, it would be easy to form a linear precipitation zone in the vicinity?

A.
This is not the type of rain cloud that is classified as a linear precipitation zone. Rather, it is a structure close to the warm front.
When the warm and damp southeast wind slides in the form of sliding on the cold air layer formed on the land side.
It is a heavy rain caused by the fact that the situation lasts for a long time, and it is considered a different type from the linear precipitation zone.

Typhoon speed is

Q.
I think that the amount of rainfall will change depending on how and when the typhoon accelerates, but will it be at least a reasonable amount of time until it passes through the Kanto region and then accelerate?

A.
As you indicated, it is currently 25 km north-northwest and 25 km per hour.
After 12 hours, it is 20km / h northwest. Since it is 20 km north after 24 hours, it is 25 km to 20 km until the typhoon arrives.
After that, it gradually accelerates after turning to the northeast, but this is not a significant acceleration either.
However, at the time of off Sanriku, the expected traveling direction / speed is expected to be 45 km / h in the north-northeast direction, and what landed around 20 km / h is 45 km off Sanriku, speeding up about double I expect that.

Q.
What were the atmospheric pressure and maximum wind speed at the time of landing of “Kanogawa Typhoon”?

A.
Landing on the Miura Peninsula, Kanagawa Prefecture, the central pressure at that time was 965 mbar. At that time, for the analysis of typhoons, only the central pressure was analyzed, and the maximum wind speed was not analyzed.

Q.
What should I pay attention to when deciding not to evacuate?
What should I pay attention to if I stay at home?

A.
What I explained at the press conference that I am now explaining the maximum wind speed expected in each place on the Japanese archipelago scale, but the local wind station has the maximum wind speed and the maximum instantaneous wind speed expected in the area. We provide detailed forecasts with the prefecture weather information to be announced, so please refer to the weather information and warnings etc. announced by such local weather stations, and see how much wind seems to blow at your place. I would like to.
In particular, for example, there are still many blue-sheeted houses in the affected areas of Chiba Prefecture, Izu Islands, Typhoon No. 15, etc. In such a case, the typhoon this time is a certainty. Because it is assumed that it will be dangerous because it will be a heavy rain and a considerable storm, staying in the house, anyway, this time the evacuation center is set up in the evacuation center opened by the local municipalities If you want to use it, or if you have relatives at an early stage, I would like you to take measures to escape from that difficulty, such as evacuating to such a place.