Atmosphere unstable due to front and typhoon; rough weather over wide area over the weekend

2026/09/02 21:37

The atmospheric conditions near Japan are extremely unstable due to the effects of fronts and typhoons.
From around the 3rd (Thursday) to the 5th, there is a risk of heavy rain and increased rainfall mainly from the Pacific side of western to eastern Japan.

A low pressure system is moving northeast near western Hokkaido, and a front extending from this low pressure system is reaching from southern Hokkaido, the Tohoku region, and the central Japan Sea to the vicinity of the Tsushima Strait.
An anticyclone is located far to the east of Japan, and its marginal flow extends to the south of Japan.



Typhoon No. 24 is near the Amami Islands and is slowly moving north.
In addition, Typhoon No. 18 has developed into a typhoon again in the South China Sea and is moving slowly east-northeast.

Southerly moist air currents blowing in from the east side of these typhoons and southerly winds from the distant high-pressure edge flow into the front area, resulting in a pressure distribution that continuously supplies warm, humid air near the front.

Tomorrow, the 3rd (Thursday), there will be a trough of atmospheric pressure near Japan, and convective clouds are expected to develop on the front from Hokkaido to Honshu.
There is a risk of heavy rain accompanied by thunder near the front, and there is a possibility of locally very heavy rain.



Because Typhoon No. 24 moves slowly, the inflow of humid air continues for a long period of time, making it difficult to resolve the unstable atmosphere.

The front is expected to stay near the southern coast of Honshu around the 5th, raising concerns about prolonged rain.
Please pay attention to the latest information regarding the movement of fronts and typhoons.



From around the 3rd to the 5th, there is a risk that heavy or extremely heavy rain will continue to fall over a wide area, mainly on the Pacific side of western to eastern Japan, and the total amount of rainfall will increase.
In areas where the ground has become loose due to heavy rain, even a small amount of rainfall can increase the risk of landslides. Depending on the path of the typhoon and the movement of the front, heavy rain may continue until around the 7th, and the total rainfall may even increase.



There is a risk of sudden rise in river water, flooding of low-lying areas, and a sudden increase in the risk of landslides. Avoid approaching dangerous areas, and if you live in a landslide warning area, please consider evacuating early.
Please pay close attention to the latest weather information and evacuation information from local governments.

[Typhoon information] Typhoon No. 24 (Krovan) is moving slowly, the autumn rain front is stationary near Honshu, and there is a risk of heavy rain over a wide area

2026/09/02 19:40

As of 6:00 pm on Wednesday the 2nd, Typhoon No. 24 (Krovan) is located approximately 280 km south of Minami Daito Island and is moving slowly north.

Typhoon No. 24 will continue to move northward, and is expected to move south of Amami City on the 3rd (Thursday) and north-northwest of Amami City on the 4th (Friday). After that, its movement will slow down, and it will most likely remain stationary from south of Kyushu to south of Japan.



#Typhoon No. 24 2nd (Wed) 6:00 pm
==================/brCenter location South Approximately 280 km
south of Daito Island Travel direction, speed North Slow
Central pressure 994 hPa
Maximum wind speed 18 m/s (near the center)
Maximum instantaneous wind speed 25m/s
==================

In the Nansei Islands, please be careful of landslides, flooding of low-lying areas, and rising water in rivers from around the 5th (Saturday), and be careful of strong winds and high waves accompanied by swells.



Also, there is a low pressure system with a front near northern Japan, which is moving east-northeast. After this, the front is expected to slowly move southward near Honshu on the 3rd (Thursday), and then come to a standstill near the southern coast of Honshu by the 4th (Friday).

The front will remain stationary, and warm, humid air moving north on the east side of the slow-moving typhoon will continue to flow toward the south of the front.
For this reason, from tomorrow 3rd (Thursday) to 5th (Saturday), heavy to extremely heavy rain will continue to fall over a wide area, mainly on the Pacific side of eastern and western Japan, and there is a risk that the total amount of precipitation will increase.
Depending on the path of the typhoon and the movement of the front, heavy rain may continue until around the 7th (Monday).

In eastern and western Japan, please be careful of landslides, flooding of low-lying areas, and rising river waters from the 3rd (Thursday) to the 7th (Monday).

Also, be careful of strong wind gusts such as lightning strikes and tornadoes. If there are signs that a cumulonimbus cloud is approaching, please take precautions such as moving inside a building. There is also a risk of hail, so please be careful when managing crops and agricultural facilities.

Please pay attention to future disaster prevention weather information and evacuation information from local governments. Also, please check the level of risk in your area using Kikikuru from the Japan Meteorological Agency website.

Weather for tomorrow 3rd (Thursday) Front heading south, typhoon approaching

2026/09/02 18:02

The autumn rain front is expected to move slowly southward, and Typhoon No. 24 is expected to move northward over the Nansei Islands. Moist air flowing along the edge of the high-pressure system overhanging the eastern ocean and the moist air around the typhoon will flow into the autumn rain front, causing rain to fall over a wide area from Hokkaido to Okinawa. The severe summer heat in eastern and western Japan is expected to ease a little.



Typhoon No. 24 is expected to approach Okinawa and Amami. In the Nansei Islands, you need to be careful about rain, strong winds, and high waves. It will be uncomfortably hot and humid throughout the day.
Rain is expected over a wide area from Hokkaido to Kyushu. Please take an umbrella with you when you go out. There is a risk of heavy rain accompanied by thunder mainly from the Pacific side of western Japan and Hokuriku to the Sea of Japan side of northeastern Japan.
The harsh summer heat in eastern and western Japan is expected to subside due to the rain. The maximum temperature is expected to be around 30c from Kanto to Kyushu. However, due to the high humidity, it will likely be hot and humid. The expected maximum temperature in northern Japan is around 25c, which will feel relatively cool even during the day.

Weekly weather Typhoon No. 24 + Autumn rain front may cause prolonged effects of heavy rain over a wide area of Honshu

2026/09/02 07:52

As of 6 a.m. today, Wednesday, the 2nd, Typhoon No. 24 is mostly stationary in the south of Japan.

#Typhoon No. 24 Wednesday, 2nd, 6:00 a.m.
==================
Center location: South of Japan
Moving speed: Almost stagnant
Central pressure 996hPa
Maximum wind speed 18m/s (near the center)
Maximum instantaneous wind speed 25m/s
=================



Typhoon No. 24 is expected to move slowly northward and approach Okinawa from tomorrow 3rd (Thursday) to the 4th (Friday). After that, Typhoon No. 24 slows down and is expected to stall near the Amami region before moving southeast. However, there is great uncertainty in predicting the future course, and there is a wide range of possibilities.

In Okinawa and Amami, where Typhoon No. 24 is approaching, the winds will gradually become stronger and the waves will become higher with swells on the sea. Please be careful of strong winds and high waves, and be careful of flooding of low-lying land and landslides due to heavy rain, as well as rising water levels and flooding of rivers.

There is a risk of warning-level heavy rain near Honshu, even in areas far from Typhoon No. 24.



The autumn rain front is likely to remain stationary in the vicinity of Honshu, and as Typhoon No. 24 moves slowly, it is expected that warm, moist air from the typhoon will continue to be sent to the front, extending the period of rain. In addition, due to the influence of cold air in the upper atmosphere, atmospheric conditions will become unstable and there is a risk of warning-level heavy rain over a wide area. The effects of heavy rain will be prolonged and total rainfall will be high.

Pay attention to the latest weather information and typhoon information that will be updated in the future, and be careful of landslides caused by heavy rain, flooding of low-lying areas, and rising and flooding rivers. In case of an emergency, please take all possible precautions against heavy rain, such as reconfirming your evacuation route, securing emergency supplies, emergency water and food, etc.

Weather forecast for today, the 2nd (Wednesday): Northern Tohoku is on high alert for heavy rain disasters; western and eastern Japan also beware of localized thunderstorms

2026/09/02 07:08

Today, the 2nd (Wednesday), a low pressure system above the autumn rain front is moving through the Sea of Japan. Typhoon No. 24 is stationary in the south of Japan, and another typhoon No. 18 is in the South China Sea, sending warm, humid air toward the autumn rain front.



In the early hours of today, a linear rain band occurred in Aomori Prefecture, and heavy rain of more than 80 mm per hour was reported, and a series of meteorological and disaster prevention bulletins (record-breaking heavy rain in a short period of time) were announced. In Aomori Prefecture, there are areas where level 4 heavy rain danger warnings and landslide danger warnings have been announced.
Also, there are places in Akita Prefecture where heavy rain was observed, and a level 4 landslide warning has been announced in Fujisato Town, Akita Prefecture.

In the northern Tohoku region, there will be places where there will be heavy to very heavy rain, especially in the morning. Please be extremely cautious of landslides, flooding of low-lying areas, and rising and flooding rivers in Aomori and Akita prefectures.



From southern Tohoku to Kyushu, atmospheric conditions are unstable even in sunny areas. There is a high probability of lightning occurring over a wide area, and from the afternoon onwards there will be localized thunderstorms, mainly in inland and mountainous areas, and heavy rain is likely to occur in some places. Pay attention to changes in the sky.

In Okinawa, even areas with sunny spells will gradually experience rain, with localized thunderstorms. Also, please be careful of high waves and strong winds caused by Typhoon No. 24.



Due to the influence of warm and humid air from Tohoku to Kyushu, there are many places where the temperature is over 30c during the day, and there are likely to be places in the Kanto region where the temperature will be significantly higher than the day before. In western Japan, in areas where southerly winds flow over the mountains, temperatures can easily exceed 35 degrees Celsius, and the lingering heat will be severe. Please be careful about heat stroke.

There is a risk of heavy rain in northern Japan from tonight until the 3rd day after tomorrow due to the influence of a low pressure system.

2026/09/01 19:15

Today, the 1st (Tuesday), a low pressure system with a front in the central Japan Sea is moving east-northeast. This low pressure system is expected to move toward Hokkaido into tomorrow, the 2nd (Wednesday).

In Hokkaido, which is close to a low-pressure area, there will be places where heavy rain will be accompanied by thunder. Depending on the degree of rain cloud development, there is a risk of heavy rain reaching warning level, so please be careful.

Also, due to the influence of warm, humid air flowing toward fronts and low pressure systems and cold air in the upper atmosphere, there will be places in the Tohoku and Hokuriku regions where heavy rain will be accompanied by thunder.
In the Hokuriku region, the ground is loose in some places due to the rain that has fallen so far. Even low rainfall increases the risk of landslides, so please avoid approaching dangerous areas such as cliffs.





In the Hokkaido region, a low-pressure system accompanied by a front is expected to move into the area into next Wednesday, the 2nd. In the southern part of Hokkaido on the Sea of Japan side and the western part of the Pacific Ocean side, heavy rain accompanied by thunder will fall in some places from late Tuesday night on the 1st today until noon on Wednesday the 2nd tomorrow.

Please be careful of flooding of low-lying land, rising river water, and landslides due to heavy rain from early morning until evening on the 2nd tomorrow (Wednesday). Depending on the degree of rain cloud development, there is a risk of heavy rain reaching warning level.

In addition, there is a risk of tornadoes, strong wind gusts, lightning strikes, and hail from late today (Tuesday) to late tomorrow (Wednesday) 2nd.
Please be careful about outdoor activities and crop management. If there are signs that a cumulonimbus cloud is approaching, please take precautions such as moving to a sturdy building.



In the Tohoku region, please be careful of landslides, flooding of low-lying areas, and rising river waters due to heavy rain from early morning on the 2nd (Wednesday) tomorrow until Thursday the 3rd (Thursday).
Also, please be aware of damage to crops and agricultural facilities from tornadoes and other violent gusts, lightning, and hail from early morning until early evening on the 2nd (Wednesday) tomorrow.

In the Hokuriku region, the front is expected to move south from the 3rd (Thursday) to the 4th (Friday), so there is a possibility that the effects will be prolonged and there will be widespread warning-level heavy rain. From the 3rd (Thursday) to the 4th (Friday) the next day, please be careful of landslides, flooding of low-lying areas, and rising river waters.
Also, from the morning of tomorrow 2nd (Wednesday), please be careful of damage to crops and agricultural facilities due to violent gusts such as tornadoes, lightning strikes, and hail.

[Typhoon No. 24] Typhoon + autumn rain front leading to heavy rain in the second half of the week

2026/09/01 12:42

At 9:00 am on September 1st, a tropical cyclone became Typhoon No. 24 in the south of Japan at 22 35'N latitude and 131 55'E longitude.
The typhoon is currently at a standstill.
The central pressure is 996hPa, the maximum wind speed near the center is 18m/s, and the maximum instantaneous wind speed is 25m/s. Strong winds of 15m/s or more are blowing within 560km to the south and 390km to the north of the center.



After this, Typhoon No. 24 is expected to reach approximately 150 km northwest of Minami Daito Island on the morning of the 3rd and move north-northwest.
It is expected to head toward the waters near the Amami Islands on the morning of the 4th, and then change course to the north.
After the 5th, it is expected to slow down its movement and become stagnant in the south of Japan. From the 4th onwards, the forecast is highly uncertain, making it difficult to determine the course.

Also, from the 4th onwards, the front is expected to remain stationary near Honshu, making it easy for rain clouds to form.





Southerly winds from the typhoon will cause warm, humid air to flow over the front, leading to the front becoming more active and potentially causing heavy rain.
Please pay close attention to future typhoon and weather information.

Summary of weather and temperature (August 23rd to August 29th) Record heavy rain in Hokuriku Level 5 heavy rain special warning announced in Ishikawa-Toyama

2026/09/01 11:50

This is a summary of the weather and temperature from August 23rd to August 29th, 2026.

[About this period's weather]
#Characteristics of pressure distribution
On the 23rd, Typhoon No. 18 moved west-northwest near Ogasawara, and Typhoon No. 19 almost stopped in the Gulf of Tonkin. Typhoon No. 20 moved southwest through the Taiwan Strait. On the 24th, extremely strong typhoon No. 18 moved westward from the south of Japan. Additionally, Typhoon No. 21 formed east of the Philippines, and a cold front moved southward over Hokkaido. On the 25th, a strong typhoon No. 18 moved westward near the main island of Okinawa. A low pressure system accompanied by a front passed from the Sea of Japan to the southern part of Hokkaido. On the 26th, the autumn rain front stalled from the Sea of Japan to the Tohoku region, and powerful Typhoon No. 18 passed near Okinawa and moved westward through the East China Sea. On the 27th, an autumn rain front extended from the Sea of Japan to the Tohoku region, and powerful Typhoon No. 18 moved westward through the East China Sea. On the 28th, a low-pressure system with cold air in the sky moved northeast from the vicinity of Hokkaido to the waters near the Chishima Islands, and an autumn rain front extended to the vicinity of western and eastern Japan. In addition, Typhoon No. 18 moved westward through the East China Sea and made landfall in central China. On the 29th, an autumn rain front extended from the Sea of Japan to eastern Japan. Additionally, Typhoon No. 18 turned into a tropical cyclone in central China.
#Precipitation
On the 23rd, heavy rain occurred in the Sakishima Islands due to Typhoon No. 20. Daily precipitation on Yonaguni Island is 118mm. On the 24th, locally heavy rain occurred from Tohoku to Kinki. Tomi City, Nagano Prefecture 40.5mm/h. On the 25th, heavy rain fell in southern Hokkaido due to warm and humid air. At Hobetsu in Mukawa Town, it reached 61mm/h, the highest in recorded history. In addition, a linear rain belt formed in the Amami region due to Typhoon No. 18. On the 26th, it rained in Okinawa/Amami due to Typhoon No. 18. Daily precipitation exceeds 240 mm in Amagi, Kagoshima Prefecture. On the 27th, extremely heavy rain occurred from Hokkaido to Tohoku in front of a low-pressure system in the Sea of Japan. Record-breaking heavy rain of 100mm/h in a short period of time in Mashike Town, Hokkaido. Additionally, due to the effects of the autumn rain front, a Level 5 heavy rain special warning was announced in Ishikawa and Toyama prefectures. The heaviest rainfall in recorded history was 300 mm in Himi City, Toyama Prefecture, and 288 mm in Hakui City, Ishikawa Prefecture. On the 28th, a linear precipitation band occurred in Hokkaido. 70.5mm/h in Nemuro City, Hokkaido. Also, due to the influence of the autumn rain front, there was extremely heavy rain on the Sea of Japan side. Himi City, Toyama Prefecture 75mm/h. On the 29th, extremely heavy rain was observed around Hokuriku due to the influence of the autumn rain front. 64.0mm/h was observed in Miyama, Fukui City, Fukui Prefecture.
#Temperature
On the 23rd, western Japan was covered with a tall high-pressure system, causing clear skies and rising temperatures. On the 24th, it was sunny from western Japan to eastern Japan, and temperatures rose with warm air reaching 18 C or higher at an altitude of around 1,500 meters. 39.5c observed in Otsu City, Shiga Prefecture. At three other locations, the temperature exceeded 39 degrees Celsius, dangerously hot and exceeding body temperature. On the 25th, a high pressure area existed from western Japan to eastern Japan. The downflow of Typhoon No. 18 strengthened the power of the high pressure system, and there were four locations where the temperature exceeded 39 degrees Celsius, including 39.1 degrees Celsius in Yatsushiro City, Kumamoto Prefecture. On the 26th, western and eastern Japan were covered in a Pacific anticyclone, resulting in a severe lingering heat. Extremely hot days of 40c or higher were observed at two locations in Fukuoka Prefecture. Extremely hot days also affected 246 locations. On the 27th, a Pacific high-pressure system extended into western Japan, causing clear skies and rising temperatures in western Japan, resulting in extremely hot days in some places. On the 28th, there were some places in Kyushu and Shikoku that were covered in high pressure and the sun hit, making it an extremely hot day. On the 29th, the severe summer heat continued in western Japan. In the Kanto region, which was north of the front, the weather was cloudy and rainy, and the temperature did not rise during the day, making it moderately hot.



# Weather summary for this period (August 23rd to August 29th)
Average temperatures were above normal across the country, and in particular in northern Kyushu and the Seto Inland Sea in western Japan, there were many days when the sky was covered by a tall high-pressure system with warm air, resulting in record high temperatures of more than 3 degrees above normal. On the other hand, in Hokkaido, temperatures were below normal in the northern part of the island due to the influence of cool air from the Sea of Okhotsk High.
Due to the influence of humid air, the autumn rain front that extends from the Sea of Japan to the vicinity of northern Japan became more active, with many areas centered on the Sea of Japan and Hokkaido exceeding normal levels, and some areas around Hokuriku exceeding 400%. On the other hand, on the Pacific side, which was far from the front, many places were covered by high pressure and there were many sunny days that made it difficult for heavy rain to occur, resulting in a tendency for rainfall to be much lower than normal in many areas. On the other hand, the Nansei Islands received much more rainfall than normal due to Typhoon No. 18.
Sunshine hours were above normal in many locations as western Japan was covered in high pressure and had many sunny days. In eastern and northern Japan, many places were cloudy and rainy due to the influence of humid air and fronts, and temperatures were at or below normal. In the Nansei Islands, there were many cloudy and rainy days due to Typhoon No. 18 and humid air, and the weather was well below normal.

Today, September 1st (Tuesday), it is dangerously hot in western Japan, and a low pressure system has formed in the Sea of Japan.

2026/09/01 11:09

Today, the 1st (Tuesday), the area around Japan will be covered in high pressure, and strong sunlight will reach western Japan.
Temperatures are expected to reach 38 degrees Celsius in Toyooka City, Hyogo Prefecture, Tottori City, Tottori Prefecture, and Yonago City, Tottori Prefecture, and the rest of western Japan is also at risk of dangerously hot temperatures exceeding body temperature. Please take all possible measures to prevent heat stroke.



Meanwhile, a low pressure system that will form on a front near central China is expected to continue to develop over the 2nd, moving northeast and reaching west of Hokkaido.



In Hokkaido, the rain is expected to become heavier mainly in the southern part of Hokkaido, and the rain is expected to spread further on the 2nd (Wednesday). Please check the latest information frequently.



Also, as moist air flows toward low pressure, atmospheric conditions will become unstable in the afternoon over a wide area from northern to western Japan. Be careful of sudden thunderstorms and strong rain, and be sure to check the rain cloud radar when you go out.

September starts with severe lingering heat mainly in western Japan, cloudy and rainy in northern Japan

2026/09/01 06:58

Today, September 1st (Tuesday), the lingering heat continues to be severe, especially in western Japan, and many places are likely to experience extreme heat with temperatures exceeding 35c. On the other hand, clouds tend to spread over Hokkaido and Tohoku, and rain will spread over the area in the afternoon. In areas that have experienced heavy rain, such as Hokuriku, please be careful of landslides even if there is a little rain.



Today's 1st (Tuesday), the start of September, will be sunny during the day and a harsh lingering heat will continue from Kyushu to the Tokai and Hokuriku regions due to the influence of the Pacific high pressure system that extends near Honshu.





The maximum temperature will rise above 35c, with temperatures in Kanazawa, Osaka, Nagasaki at 35c, Fukuoka at 36c, Hiroshima, Matsue at 37c, Kyoto and Nara at 38c, and many places will experience extremely hot days. A heatstroke warning alert has been announced in 16 prefectures, mainly in western Japan, and the risk of heatstroke will continue into September, so please continue to take precautions against the heat, such as by frequently drinking water and salt and using appropriate air conditioning.

Hokkaido and Tohoku are prone to clouds spreading due to the influence of fronts and low pressure systems, and it is likely that rain will gradually increase in many places. Please note that there is a possibility of heavy rain in Hokkaido at night.
Although there will be periods of sunshine in the Kanto region, clouds will likely spread. There is a chance of showers mainly in the north. Hokuriku will also have periods of sunshine, but the atmospheric conditions will become unstable in the afternoon, leading to heavy rain in some places.

Although the sun will shine during the day from Kinki to Kyushu, the atmospheric conditions will be unstable in the afternoon, and localized areas are likely to see heavy rain accompanied by thunder.