[Marine Summary] Typhoons No. 7 and No. 8 approach, large storms near the typhoons (June 21-27, 2026)

2026/07/01 03:57

Due to the effects of the low pressure system, barges were closed throughout the Sea of Japan. In the second half of the
period, typhoons No. 7 and No. 8 approached, causing major damage in the vicinity of the typhoons.
Below is a summary of the ocean (June 21-27, 2026)



#Pressure distribution and waves
On the 21st, a low pressure system moved eastward in the Sea of Japan, causing waves to rise throughout the Sea of Japan. On the 22nd, waves continued to be high in Japanese waters. Meanwhile, to the east of Kanto, a low pressure front has formed and is moving eastward. Waves rose off the coast of Sanriku and it became a barge. From the 23rd to the 25th, Typhoon No. 7 approached the Nansei Islands. The waves increased near the typhoon and became large, with wave heights of around 7 meters. On the 26th, typhoons No.7 and No.8 headed north. Waves increased near the Nansei Islands and the southern coast of Honshu. On the 27th, Typhoon No. 8 passed near the southern coast of Kanto, and Typhoon No. 7 passed from the southern coast of western to eastern Japan. Waves were rising from the south of Japan to the Nansei Islands, with wave heights of around 5 meters.



#Sea surface temperature
Sea surface temperatures in the Japanese waters continued to be about 1c higher than normal, although the area where the sea surface temperature is much higher than normal has shrunk. In eastern Honshu, the area where sea surface temperatures are significantly higher than normal has shrunk, but temperatures continue to be higher than normal over a wide area. In the northern East China Sea, the area where sea surface temperatures are significantly higher than normal is shrinking. In the south of Japan, the area of sea where sea surface temperatures are much lower than normal is shrinking. In the south of Okinawa, sea surface temperatures continue to be lower than normal in areas. In the sea near Chichijima, the area where sea surface temperatures were significantly higher than normal decreased, but the sea surface temperatures continued to be higher than normal over a wide area.

Weather for tomorrow 1st (Wednesday): Rain in a wide area in western Japan

2026/06/30 18:25

The seasonal rain front is expected to gradually move northward and stay near Honshu.



Rain is expected to spread further east, with rain expected to cover a wide area of western Japan.
It will rain in many places in Kyushu, Shikoku, and Chugoku in the morning, and it will start raining in the afternoon in the Kinki and Tokai regions as well. Please be wary of heavy rain accompanied by thunder in Kyushu.
The Kanto region is expected to continue to be cloudy and humid. Northern Japan will be covered in high pressure and will have many sunny days, but mornings and evenings will be cool, and the temperature difference throughout the day is likely to be large.
There is a risk of sudden thunderstorms in inland Honshu due to cold and humid air in the upper atmosphere. Please bring a folding umbrella.

Weather for today, the 30th (Tuesday): The rainy season front is stationary from southern Kyushu to the southern coast of Honshu. Southern Kyushu is on alert for heavy rain.

2026/06/30 10:27

Today, the 30th (Tuesday), the rainy season front is expected to extend from southern Kyushu to the southern coast of Honshu. There is a risk of warning-level heavy rain in the Satsuma/Osumi, Tanegashima, and Yakushima regions into the late evening. In addition, the atmospheric conditions will be unstable due to the effects of cold and humid air in the upper atmosphere, and showers and thunderstorms are likely to occur in places in the afternoon.



In southern Kyushu, it will rain intermittently, and there will be places where it will fall heavily with thunder. There is a risk of warning-level heavy rain, and you need to be careful about landslides, flooding of low-lying land, and rising river waters. Although there will be sunshine from the Chugoku region to Hokkaido, rain and thunderstorms are expected in some places in the afternoon. Additionally, the seasonal rain front will move northward to the southern coast of Kyushu, and warm, humid air will flow toward the front from the south. It will be cloudy in Kyushu and Shikoku, and it will rain here and there. There is a risk of warning-level heavy rain in the Satsuma/Osumi, Tanegashima, and Yakushima regions into the late evening. Please be careful of landslides, flooding of low-lying land, and rising river waters.

On the other hand, it will be sunny or cloudy from the Chugoku region to Hokkaido, and there will be some rain and thunderstorms in the afternoon, mainly along the mountains. Even if it is sunny, please be careful of sudden heavy rain, lightning strikes, and gusts of wind.
After the rainy season, Okinawa is expected to be mostly sunny, with strong sunlight shining during the day.

Weather for today, the 30th (Tuesday): The rainy season front is stationary from southern Kyushu to the southern coast of Honshu. Southern Kyushu is on alert for heavy rain.

2026/06/30 06:37

Today, the 30th (Tuesday), the rainy season front is expected to extend from southern Kyushu to the southern coast of Honshu. There is a risk of warning-level heavy rain in the Satsuma/Osumi, Tanegashima, and Yakushima regions into the late evening. In addition, the atmospheric conditions will be unstable due to the effects of cold and humid air in the upper atmosphere, and showers and thunderstorms are likely to occur in places in the afternoon.



In southern Kyushu, it will rain intermittently, and there will be places where it will fall heavily with thunder. There is a risk of warning-level heavy rain, and you need to be careful about landslides, flooding of low-lying land, and rising river waters. Although there will be sunshine from the Chugoku region to Hokkaido, rain and thunderstorms are expected in some places in the afternoon. Additionally, the seasonal rain front will move northward to the southern coast of Kyushu, and warm, humid air will flow toward the front from the south. It will be cloudy in Kyushu and Shikoku, and it will rain here and there. In southern Kyushu, it will rain intermittently, and in some places it will rain heavily with thunderstorms. There is a risk of warning-level heavy rain in the Satsuma/Osumi, Tanegashima, and Yakushima regions into the late evening. Please be careful of landslides, flooding of low-lying land, and rising river waters.

On the other hand, it will be sunny or cloudy from the Chugoku region to Hokkaido, and there will be some rain and thunderstorms in the afternoon, mainly along the mountains. Even if it is sunny, please be careful of sudden heavy rain, lightning strikes, and gusts of wind.
After the rainy season, Okinawa is expected to be mostly sunny, with strong sunlight shining during the day.

Weather in the Kanto region looks like the rainy season ahead. Be careful of heavy rain. Weekly weather in the Kanto region

2026/06/29 22:26

From now on, the front will stay near Honshu, and the Kanto region is likely to experience sluggish weather typical of the rainy season.



Tomorrow, the 30th (Tuesday), the Kanto region will be gently covered by a high pressure system centered over the Sea of Japan. On the other hand, the seasonal rain front that extends south of Japan will move northward, so it is expected to be affected by humid air. There will be periods of sunshine during the day, but clouds will likely spread. There is a possibility of rain in the evening, so it's a good idea to bring a foldable umbrella with you when you go out.



The front is expected to move further north tomorrow, July 1st (Wednesday). Clouds will likely spread over the Kanto region.

The low pressure front is expected to move eastward from the 2nd (Thursday) to the 3rd (Friday). It will rain widely in the Kanto region. Looks like it's time for an umbrella.
There is a possibility that the rain will become stronger locally, resulting in heavy rain. Please check the latest information.

After the 4th (Saturday), the front will remain stationary near Honshu, and the weather will continue to be cloudy.

Please note that the way the rain falls will change depending on the location of the front and the degree of development of the low pressure above the front, so please check the latest weather forecast and prepare for heavy rain disasters.



Even if the clouds tend to spread, the maximum temperature is expected to be higher around the 30th (Tuesday) and July 1st (Wednesday). There are some places where midsummer days are expected to reach 30 degrees Celsius, so please take precautions against heat stroke.
Even on rainy days, the high humidity makes it difficult for sweat to evaporate, making it difficult for your body temperature to drop and putting you at risk of heatstroke. Don't forget to take precautions against heatstroke, such as staying hydrated and taking breaks.

[Breaking news] Rainy season ends in Okinawa 8 days later than normal

2026/06/29 14:37

The Okinawa region is covered by the Pacific anticyclone and is mostly sunny. It is expected that many sunny days will continue to be covered by the Pacific high pressure system.

The Japan Meteorological Agency has announced that the rainy season appears to have ended in the Okinawa region.

The end of the rainy season in Okinawa region June 29th (8 days later than normal)



*This information is released as a preliminary report based on the current weather history and the weather outlook for about a week or more. It may be reviewed in the fall.

Level 4 landslide warning for Amami region; heavy rain possible into the 30th (Tuesday)

2026/06/29 12:14

The rainy season front is stationary in the south of Honshu.
Warm and humid air is flowing towards the seasonal rain front near Tanegashima and Yakushima, causing extremely unstable atmospheric conditions in Kagoshima Prefecture. As a result, cumulonimbus clouds have developed locally in the Amami region, and currently active rain clouds and thunderstorms have been observed.



Today, into the evening of the 29th, there will be localized very heavy rain accompanied by thunder and heavy rain, resulting in heavy rain.
The expected rainfall per hour on the 29th is high in places,
Kagoshima Prefecture (excluding the Amami region) 40mm
Amami region 60mm

From 12:00 on the 29th The predicted 24-hour precipitation by 12:00 on the 30th is high in some places: Kagoshima Prefecture (excluding Amami region) 120 mm
Amami region 150 mm



A level 4 landslide danger warning has been announced in the Amami region.
Please evacuate everyone from dangerous slopes and cliffs.

Also, please be careful of flooding of low-lying areas, rising river levels, lightning strikes, and strong gusts of wind such as tornadoes.
If there are signs that a cumulonimbus cloud is approaching, please take precautions such as moving inside a building.

Weekly weather: Rainy season front stagnant near Honshu; rainy days continue in western and eastern Japan; rainy season is almost over in Okinawa

2026/06/29 07:09

Looking at the weather map for the next week, it looks like the rainy season front will remain stationary near Honshu for many days. In western and eastern Japan, there will be many cloudy and rainy days, especially on the Pacific coast.

A low pressure system is expected to move over the seasonal rain front from around the 1st to the 3rd. When a low pressure system passes, the seasonal rain front becomes more active, and there is a risk of heavy rain or heavy rain accompanied by thunder. Sufficient attention must be paid to landslides, flooding of low-lying areas, and rising river waters. Even after the low pressure system passes, the rainy season front tends to remain stationary, so cloudy and rainy days are likely to continue from western to eastern Japan.
Even on rainy days, the temperature is expected to reach nearly 30 degrees Celsius in some places, and the humid, humid days typical of the rainy season will continue.

On the other hand, Okinawa is expected to have many sunny days in the future, and the end of the rainy season is expected to be near. However, Okinawa/Amami is expected to experience ``significantly higher temperatures'' than normal from around the 1st, and the Japan Meteorological Agency has released early weather information regarding high temperatures. To avoid heatstroke, please take precautions such as hydrating frequently, supplementing with salt, and taking adequate breaks.

Weather forecast for tomorrow, the 29th (Monday): Watch out for sudden rain and thunderstorms in the afternoon, especially in the inland areas of eastern Japan and Hokkaido, and along the mountains.

2026/06/28 20:38

Tomorrow, the 29th (Monday), the rainy season front will be stationary in the south of Honshu. Rain is likely to fall in Okinawa and Amami, which are close to the rainy season front, and southern Kyushu and the Amami region should be careful of heavy rain accompanied by thunder in the morning.



Western Japan is expected to be covered in high pressure and have many sunny days. In eastern Japan, clouds tend to spread around the Kanto region, and there are likely to be some areas with showers due to the influence of local fronts. In other areas, the weather forecast shows clear skies, but there is a possibility that the weather could change suddenly in the afternoon, especially in the inland areas and mountains of eastern Japan and Hokkaido.



The effects of warm, humid air brought in by typhoons and the seasonal rain front will remain in areas around Honshu, and strong cold air is expected to flow into the skies over northern Japan. As a result, atmospheric conditions become unstable and there is a high probability that thunderclouds will form and develop in the afternoon.
The Koshin region and Hokkaido are prone to sudden rain and thunderstorms, and in the Koshin region, please be careful of heavy rain accompanied by thunder. It is likely that there will be localized rain and thunderstorms in the afternoon, even in parts of the southern Tohoku region, northern Kanto region, and inland and mountainous areas of the Tokai region. Even if it's not raining when you go out, it's a good idea to carry a folding umbrella.

The rainy season front is stagnant. Okinawa region should be careful of heavy rain today, the 28th. Heavy rain is expected in southern Kyushu and Amami regions into tomorrow 29th.

2026/06/28 12:32

Today, the 28th (Sunday), the rainy season front is extending from the continent to the south of Japan, passing near the Nansei Islands. The rainy season front is expected to slowly move northward into tomorrow, the 29th (Monday).

Please be careful of heavy rain caused by the rainy season front in the Okinawa region today, the 28th (Sunday). In the southern Kyushu and Amami regions, there is a risk of heavy rain into tomorrow, the 29th (Monday), so caution is advised.



This morning, 39.5 mm of heavy rain was observed in the hour up to 8:36 on Iriomote Island in Taketomi Town, Yaeyama District, Okinawa Prefecture, and 33.0 mm in the hour up to 7:24 in Kitahara, Kumejima Town, Shimajiri District, Okinawa Prefecture.



Today, the 28th (Sunday), atmospheric conditions in the Okinawa region have become extremely unstable due to the influence of moist air flowing into the front.

In the Yaeyama region, be careful of flooding of low-lying areas, rising water levels, and flooding of rivers, and be careful of landslides.
In the main island of Okinawa, be careful of landslides, flooding of low-lying areas, and rising river waters.
Even in the Miyakojima region, be careful of landslides and avoid flooding of low-lying areas.

In the Yaeyama region and Okinawa main island region, please be careful of strong gusts such as lightning and tornadoes on the 28th (Sunday). If there are signs that a cumulonimbus cloud is approaching, please take precautions such as moving inside a building.
Also, in the Miyakojima region, you need to be careful about lightning strikes, gusts of wind, and sudden heavy rain under developed cumulonimbus clouds.




Southern Kyushu and Amami regions also need to be careful of lightning, tornadoes, violent gusts, and sudden heavy rain through tomorrow, the 29th (Monday).
The rainy season front is expected to move northward to Tanegashima and Yakushima areas by tomorrow.
Therefore, there is a risk that cumulonimbus clouds may develop locally in Kagoshima Prefecture from the night of today, the 28th (Sunday) to late on the night of the 29th (Monday) tomorrow, and in the Amami region until late on the night of the 29th (Monday, tomorrow).
Please be careful of lightning strikes, strong gusts of wind such as tornadoes, and sudden heavy rain. If there are signs that a cumulonimbus cloud is approaching, please take precautions such as taking shelter inside a building.