"Rainy season" announced in the Amami region - entering the rainy season ahead of the rest of the country

2026/05/03 20:09

Today, the 3rd (Sunday), the Kagoshima Local Meteorological Observatory announced that the rainy season appears to have begun in the Amami region.

The start of the rainy season in the Amami region will be announced nine days earlier than normal and two days earlier than last year in 2025. This will be the first rainy season in Japan in 2026, and it will be the first time since 2019 that the rainy season will start before Okinawa.



The Amami region will continue to have many cloudy and rainy days, and the weather will continue to be unrefreshing. Depending on the weather conditions and how rain clouds develop, there is a possibility of heavy rain shortly after the start of the rainy season, so please be sure to check the latest weather information.
Okinawa will also have a lot of cloudy and rainy weather from now on. The rainy season may be coming soon.

*The rainy season is a seasonal phenomenon, and there is an average "transition" period of about 5 days between the start and end of the rainy season. Please note that this announcement of the start of the rainy season is preliminary information and will be reconsidered in the fall, and the timing may be revised.

Be careful of heavy rain, thunder, and gusty winds in eastern and western Japan and the Nansei Islands until tomorrow the 4th.

2026/05/03 18:31

The Japan Meteorological Agency has released the third general weather information regarding heavy rain, lightning, and gusts.

A low pressure system accompanied by a front is moving east-northeast across the western Sea of Japan.
This low-pressure system is expected to pass through the Sea of Japan and the Hokkaido region and move toward the waters near the Chishima Islands, and the front is expected to pass over Honshu and the Nansei Islands into the night of tomorrow, the 4th (Monday).



Atmospheric conditions are expected to be extremely unstable from eastern Japan to western Japan and the Nansei Islands from tomorrow, the 4th (Monday), due to warm, humid air flowing toward the low pressure system and front, as well as cold air in the upper atmosphere.
Be careful of landslides, flooding of low-lying areas, and rising river levels, and be careful of lightning, tornadoes, and other strong gusts of wind and hail.

If there are signs of a developing cumulonimbus cloud 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.



[Rain Forecast]
The predicted 24-hour precipitation from 18:00 on the 3rd (Sunday) to 18:00 on the 4th (Monday) will be high in the Hokuriku region
100mm
Kinki region 150mm
Okinawa region 80mm

[Disaster prevention matters]
From eastern Japan to western Japan and the Nansei Islands, please be careful of the following points from Monday the 4th.
+Landslides, flooding of low-lying land, rising river levels
+Severe gusts such as lightning strikes and tornadoes
+Damage to crops and agricultural facilities due to hailstorms

Weather for the week Today, the 3rd and 4th, a low pressure system will pass and it will rain widely. The latter half of Golden Week, the 5th and 6th, will be good days for going out.

2026/05/03 14:42

From today, the 3rd (Sunday, Constitution Day) to tomorrow, the 4th (Monday, Greenery Day), the weather is expected to deteriorate widely and rain is expected due to the effects of low pressure and fronts moving east-northeast across the Sea of Japan.
In the second half of Golden Week, from the 5th (Tuesday, Children's Day) to the 6th (Wednesday, substitute holiday), the weather will improve in many places, making it a good day to go out. However, Okinawa/Amami will continue to experience rainy weather.



Currently, a low pressure system accompanied by a front is moving east-northeast near the Tsushima Strait, causing rain to fall over a wide area of western Japan and the Hokuriku region.

The low pressure system is then expected to move east-northeast across the Sea of Japan until tomorrow, the 4th (Monday), and the front is expected to pass from eastern Japan to the Nansei Islands. The area of rain will spread to eastern and northern Japan.

Atmospheric conditions will be extremely unstable in some places as warm, humid air flows towards low pressure systems and fronts. From eastern to western Japan, heavy rain with localized lightning is expected to occur in some places from tomorrow, the 4th (Monday). Please be careful of landslides, flooding of low-lying areas, and rising river levels, and be careful of lightning, tornadoes, strong wind gusts, and hail.



Tomorrow, the 4th (Monday), the weather will gradually improve as high pressure will emerge from the west. However, there will be places on the Japan Sea side, such as northern Japan and Hokuriku, where it will continue to rain. In Hokkaido, cold air is expected to enter the sky from the afternoon of the 4th (Monday) to the 5th (Tuesday), so there will be places where wet snow will fall, mainly on the Sea of Okhotsk side.
In addition, strong winds are expected to continue, especially in northern Japan, which is close to a low pressure system.
Please check the latest information as there may be an impact on transportation.



On the 5th (Tuesday) and 6th (Wednesday), the latter half of Golden Week, the area around Japan will be covered in high pressure, and many places will be sunny. It looks like it's going to be a good day to go out. However, Okinawa/Amami will continue to experience rainy weather due to the influence of moist air around the edge of the high pressure system and a front to the south of Japan.

After Golden Week, a low-pressure system with a front from the west will move eastward from the 8th (Friday) to the 9th (Saturday), increasing clouds on the Pacific side, and it is likely to rain in some places.




Temperatures are expected to be higher than normal in some places on sunny days.
In Hokkaido, the weather is expected to be sunny and warm from the 5th (Tuesday) to the 7th (Thursday), and the weather is expected to be as warm as June to July.
In Tokyo, summer weather is expected to reach 26c from the 7th (Thursday) to the 8th (Friday) after Golden Week.
If you are planning to do outdoor leisure activities during the holidays, please take precautions against heat stroke, such as taking frequent breaks and consciously drinking water. It is also a good idea to bring a hat and a parasol to protect yourself from UV rays.

A low pressure system develops, warning of heavy rain disaster from western to eastern Japan from tomorrow 4th (Sunday)

2026/05/03 09:04

A low pressure system accompanied by a front is moving east-northeast across the Yellow Sea. This low pressure system will move east-northeast across the Sea of Japan until tomorrow, the 4th (Monday), and the front will pass from eastern Japan to the Nansei Islands. Atmospheric conditions are expected to become extremely unstable in some places as warm, humid air flows toward low pressure systems and fronts.

For this reason, rain clouds are likely to develop from western Japan to eastern Japan, and there is a risk of heavy rain accompanied by localized thunderstorms. Additionally, there is a risk of extremely heavy rain of more than 50 mm per hour, mainly on the Pacific side of western Japan, today, the 3rd.




#Expected amount of rain (in areas where there is a lot)
+24-hour precipitation expected by dawn on the 4th (Monday) tomorrow
Hokuriku region 100 mm
Kinki region 15 0mm
80mm

#Disaster Prevention Matters
From eastern Japan to western Japan, caution and vigilance are required for landslides, flooding of low-lying land, and rising river waters from tomorrow 4th (Monday). Also, be careful of strong wind gusts such as lightning and tornadoes.
If there are signs of a developing cumulonimbus cloud approaching, please take steps to ensure your own safety by moving inside a building. There is also a risk of hail, so care must be taken when managing crops and agricultural facilities.

Today's weather on the 3rd (Sunday) Rain clouds are expanding from the west. Be careful of heavy rain from western Japan to eastern Japan.

2026/05/03 06:21

Today, the 3rd (Sunday), which is Constitution Day, a low pressure system accompanied by a front will move toward the Sea of Japan. The weather is expected to go downhill from the west near Japan, with rain expected to fall in the Kanto region and other areas at night. In northern Japan, the rain is more likely to fall later in the day, so it's likely to be a day when umbrellas will be useful over a wide area.



It will rain in Kyushu from the morning due to the effects of low pressure and fronts. Rain is expected to start in Chugoku, Shikoku, and Kinki around noon.
After the evening, the area of rain will spread to eastern Japan, and it is expected to rain in the Tokai and Hokuriku regions from the evening, and in the Kanto region at night. Even if it's not raining when you go out, please prepare rain gear in time for your return.
Also, atmospheric conditions will be unstable in the afternoon as moist air flows towards the low pressure system. Rain clouds will develop mainly on the Pacific side, and there is a risk of extremely heavy rain of over 50mm per hour. Please be careful of landslides and flooding of low-lying areas.

In northern Japan, clouds tend to spread around the Sea of Japan, and the weather is not clear. After the evening, the area of rain will expand from the Sea of Japan side, and there will be periods of sunlight in the morning, and there will be places on the Pacific side where it will start to rain at night. If you are returning home late, it is a good idea to have a folding umbrella.

The temperature will be lower than the previous day in many places, mainly from western Japan to eastern Japan, but it is likely that the temperature will be typical for this time of year in many places. Even in northern Japan, it will be as warm as normal. Please be careful about the temperature difference throughout the day.

[General weather information] May 3rd to 4th: Be careful of heavy rain, thunder, and gusts of wind

2026/05/02 17:22

The Japan Meteorological Agency has released its first general weather information regarding heavy rain, lightning, and gusts.

A low-pressure system with a front near Central China is expected to move east-northeast across the Sea of Japan from the 3rd to the 4th, and the front is expected to pass from eastern Japan to the Nansei Islands.
Atmospheric conditions will be extremely unstable in some places as warm, humid air flows towards low pressure systems and fronts.



From the 3rd to the 4th, from eastern to western Japan, please be careful of landslides, flooding in low-lying areas, and rising river waters.
Also, be careful of lightning, tornadoes, strong gusts of wind, and hail.



# Rain forecast
24-hour precipitation from 18:00 on the 3rd to 18:00 on the 4th (in areas with the most)
Hokuriku region: 100 mm
Kinki region: 150 mm
Okinawa region: 80 mm

# Disaster prevention precautions
From eastern Japan to western Japan, please be careful of the following points from the 3rd to the 4th.
+Landslides, flooding of low-lying areas, rising river levels
+Severe gusts caused by lightning strikes, tornadoes, etc.
+Damage to crops and agricultural facilities due to hailstorms

+If there are signs that a developed cumulonimbus cloud is approaching (suddenly darkening of the sky, hearing thunder, sudden cold wind blowing, etc.), prioritize safety by moving inside a building.

May 2nd (Saturday) Summer days continue, temperature in Tokyo similar to late July

2026/05/02 12:39

A low pressure system is located over the ocean south of Hokkaido and is moving northeast.
This low pressure system is expected to move toward the Kuril Islands area through the night, and Hokkaido will experience rainy and cloudy weather. On the other hand, from the Tohoku region to western Japan, plenty of sunlight is expected to fall, and temperatures are expected to rise rapidly.

It will be a summer day over a wide area, with the maximum temperature expected to be 28c in Tokyo and 26c in Nagoya and Kagoshima.



It will be unusually hot for May, and the risk of heat stroke will increase as the body is not yet accustomed to the heat. Basic measures such as hydrating frequently, taking adequate breaks, and wearing a hat when going out are essential.



Many people go outdoors during the holidays, and the elderly and children are especially susceptible to the effects of the heat, so it is important for those around them to be careful. If you notice anything unusual, please seek medical attention immediately.

Tomorrow, the 2nd (Saturday), the rain will reach northern Japan. Be careful of lightning and stronger winds.

2026/05/01 19:39

Currently, there is a low pressure system with a front in the Sea of Japan, and it is moving east-northeast. This low pressure system will continue to develop as it passes near northern Japan and will continue toward the waters near the Chishima Islands through the morning of Saturday the 2nd.



Today, the 1st (Friday), rain is falling over a wide area from western Japan to northern Japan due to the influence of a low pressure system. Atmospheric conditions continue to be unstable as strong cold air is flowing into the sky for this time of year.

In Kitaibaraki, Kitaibaraki City, Ibaraki Prefecture, extremely heavy rain of 61.0 mm was observed in the hour up to 12:42, in Maizuru City, Kyoto Prefecture, 45.0 mm in the hour up to 14:44, and in Hirono, Hirono Town, Futaba District, Fukushima Prefecture, heavy rain of 40.0 mm was observed in the hour up to 13:29.
Also, due to the influence of the low pressure system, the gradient of atmospheric pressure is increasing, and the winds are increasing mainly in coastal areas.



The area of rain is gradually expanding to northern Japan. Tomorrow, the 2nd (Saturday), the weather is expected to improve as a high-pressure system approaches from the west, but rain is expected to continue in some places in northern Japan into the morning.
Even if the weather improves, there is a large pressure gradient between the low pressure system and the high pressure system moving from the west, and strong winds will continue in many areas, so please be careful when going out.

Please be careful of thunderstorms, tornadoes, severe gusts of wind, hail, and sudden heavy rain in the Tohoku and Hokuriku regions from tomorrow, the 2nd (Saturday) until dawn.
Also, very strong winds are expected to blow from the west in the Tohoku region. Please be on guard for traffic disruption and damage to buildings due to strong winds from early morning until evening on the 2nd (Saturday).

[Wind Forecast]
Maximum wind speed (maximum instantaneous wind speed) expected on the 2nd (Saturday)
Tohoku Sea of Japan side 20 meters (30 meters) over the sea
Tohoku Sea of Japan side On land 18 meters (30 meters)
Tohoku Pacific side Sea 20 meters (30 meters)
Tohoku Pacific side Land 18 meters (30 meters)

May starts with rough weather. Even if the rain stops, be careful of sudden heavy rain and lightning strikes.

2026/05/01 06:48

Today, Friday, May 1st, a low pressure system accompanied by a front will pass near Honshu. It will rain over a wide area from western Japan to eastern Japan, and the wind will be strong and the weather will be rough. In the afternoon, even in areas where the rain has stopped, there is a risk of sudden rain or thunderstorms, so please be careful.





If you look at the rain cloud radar at 6am, you can see that active rain clouds are hanging over the Tokai and Kanto areas. In the Pacific side of eastern Japan, including the Tokai and Kanto regions, the rain will intensify, especially in coastal areas, and there is a risk of heavy rain accompanied by thunder into the afternoon. Please be careful of flooding of low-lying areas, landslides, and rising river waters due to heavy rain, and be aware of the impact on transportation.



The rain may stop in some areas in the afternoon, but strong cold air will flow into the sky for this time of year. Looking at the probability of lightning, the probability of lightning occurring is high mainly in inland areas from western Japan to eastern Japan, and areas with high probability are expected to gradually move eastward. Around 6:00 p.m., there are some places near the Tokai region where the probability of lightning striking is close to 90%.
Today, even if the rain stops in the afternoon, there is a risk of sudden rain or thunderstorms. Please be aware of sudden changes in the weather, as there is a risk of lightning, tornadoes, strong wind gusts, and hail.



In northern Japan, it will gradually rain from evening to night, and the wind will become stronger, resulting in rough weather. There is a risk of heavy rain accompanied by localized thunderstorms, so please be careful of flooding of low-lying land and rising river levels due to heavy rain. In addition, there is a risk of extremely strong winds blowing in Tohoku into the second day of tomorrow, so please be careful of strong winds and high waves, especially in coastal areas.

One month forecast: High temperatures will trend nationwide after Golden Week; signs of rainy season in Okinawa and Amami

2026/04/30 20:41

On the 30th (Thursday), the Japan Meteorological Agency announced the latest monthly weather forecast for the next month.



According to the prediction results of the numerical forecast model, the average sea level pressure for one month will be lower than normal in the north of Japan, and low pressure will likely pass north of Japan more easily. On the other hand, there is a trough of weak atmospheric pressure near Honshu. Temperatures at around 1,500 meters above the ground tend to be higher than normal, and the whole country is likely to be covered in warm air.



From now on, the weather in northern Japan will change every few days, but it will be less affected by low pressure systems and fronts, and there will be more sunny days than normal. Precipitation is expected to remain at almost normal levels.
Similarly, the weather from eastern to western Japan is expected to change every few days, and the amount of precipitation and sunshine hours during this period are expected to remain roughly at normal levels.

However, the average temperature will be higher nationwide. After Golden Week ends, there is a strong possibility that temperatures will be higher than normal, mainly in western and eastern Japan, and it is expected to become hot until late May. It will be a summer day with temperatures above 25 degrees Celsius, and depending on weather conditions, some places may even record midsummer days with temperatures above 30 degrees Celsius. To avoid heatstroke, be sure to take precautions against the heat, such as drinking plenty of water and taking regular breaks.

Okinawa/Amami is susceptible to fronts and humid air, and many cloudy and rainy days are expected. In normal years, the rainy season starts around May 10th in Okinawa and around May 12th in Amami. It looks like the rainy season is gradually approaching. Around mid-May, there may be a period when the weather is temporarily less affected by fronts and humid air, but towards the end of May it will again be susceptible to the influence of humid air.
Precipitation is expected to remain at about the same level as usual, but the rain may become heavier at times, so it would be safer to take measures for heavy rain early.