[Kanto / Warning level heavy rain] Tomorrow's commute to work and school will coincide with the heavy rain; be careful of the temperature difference (commentary: weather forecaster Atsuko Miyake)

2026/05/20 15:01

It is expected to rain in the Kanto region tomorrow and the day after.
There is a risk of heavy rain and thunderstorms, especially tomorrow (Thursday), leading to warning-level heavy rain.
First, let's look at the forecast weather map.



Predictions for tonight, tomorrow night, and the night after.
First of all, tonight, a low pressure front is approaching from the west.
The front is expected to move northward in the Kanto region.
A low-pressure front is expected to pass through the Kanto region by tomorrow.

As warm, humid air flows towards this low pressure system and front, there is a risk of heavy rain accompanied by thunder
east.
There are likely to be warning-level heavy rains in some areas along the Pacific coast.


The day after tomorrow (Friday), the low pressure system will gradually move away, but
cold and humid air will flow in from the north.
It's going to rain on Friday, but it looks like there will be cold rain in some places.



We will be looking at the rain cloud forecast from 6pm tonight.

As the front moves northward, late at night,
rain clouds begin to cover the Kanto region.

By the time the date changes, it will be raining widely, and from early morning until dawn tomorrow,
active rain clouds are expected to cover the Kanto region, mainly in the coastal areas.
It looks like it's going to be a heavy rain.



Active clouds will continue to gather around the time of commuting to work and school tomorrow morning,
There is a risk that heavy rain will overlap with the time of commuting to work and school.

When going out, please bring a large towel or a towel
with plenty of time.



Also, active rain clouds are expected to form frequently into the afternoon tomorrow.

Please be careful of heavy rain, thunderstorms, and gusts of wind such as tornadoes.

It looks like there will be a lot of rain tomorrow night.



Let's take a look at the expected maximum temperature for Tokyo in the future.

Today is expected to be 30 degrees, a midsummer day in Tokyo, and it will be as hot as mid-July.

However, tomorrow it will be 22 degrees, similar to early May.

Friday the 22nd is expected to be as chilly as early April at 18c.

Temperatures will temporarily return to normal levels over the weekend, but next week will be full of summer heat again.


The temperature difference will be quite large from now on, so please take good care of your health.
Significantly high temperatures are expected in the Kanto region next week.
Don't put up with the heat, and try to use the air conditioner without overdoing it.



Let's take a look at the forecast for the coming week.
It will rain widely in the Kanto region tomorrow and the day after.
We need to be careful about heavy rain tomorrow.
The rain will subside tomorrow, but the temperature will be quite low, so please be careful of changes in temperature.

Although there will be a lot of clouds on Saturday and Sunday, it looks like there will be some sunshine on Saturday.

Very high temperatures are expected next week. There are likely to be places where there are consecutive midsummer days.
Please be careful about heat stroke.

From the afternoon of today, the 20th (Wednesday) to the 21st (Thursday), it will rain in Kyushu and Tohoku. There is a risk of warning-level heavy rain.

2026/05/20 12:09

From the afternoon of today, the 20th (Wednesday) to tomorrow the 21st (Thursday), a front will extend near Honshu and a low pressure system will pass through.
It will rain widely from Kyushu to Tohoku, and there will be heavy rain in some places.



Today, the afternoon of the 20th, a front will extend from western Japan to the southern coast of eastern Japan. Kyushu and Hokuriku will experience rain and thunderstorms, with some places likely to see heavy rain.
It will gradually rain in the Tokai and Kanto areas at night.

A low pressure front is expected to pass near Honshu tomorrow, the 21st.
There will be widespread rain and thunderstorms from Kyushu to Tohoku, with some places experiencing heavy rain.



There is a possibility of heavy rain in the Chugoku region and Hokuriku region from this time until the 21st, and in the Tokai and Kanto-Koshin regions from the morning of the 21st tomorrow onwards.
Please be careful of landslides, flooding of low-lying land, and rising river waters.

Please pay close attention to future information.

Weather for today, the 20th (Wednesday): Rain expands from the west; rain begins late in the night in the Kanto region

2026/05/20 07:14

Today, the 20th (Wednesday), a front is expected to approach from the west. The weather will turn downhill from the west, and rain will begin in the Kanto region late at night.



Due to the influence of the front, clouds will spread over western Japan from the morning, and the area of rain is expected to gradually expand. Caution is required as moist air will flow towards the front, causing heavy rain and thunderstorms mainly on the Pacific side.
In the afternoon, rain is expected to spread to eastern Japan, and in the Tokai and Hokuriku regions from the evening onwards. Please prepare rain gear according to the time you return.

The Kanto and southern Tohoku regions will see some sunshine in the morning, but clouds will gradually spread and rain is expected to begin at night. If you will be returning late, please bring rain gear.
On the other hand, there will be periods of cloud cover in the northern Tohoku region, but sunshine is expected. The weather isn't bad and it looks like we can hang our laundry outside to dry.

In Hokkaido, clouds tend to spread throughout the prefecture, and there will be some places with showers. It's a good idea to carry a folding umbrella just in case when you go out.


Temperatures will rise, especially in sunny areas. There are likely to be places in the Tohoku and northern Kanto regions where it will be midsummer. Please be careful of heat stroke.
Even in western Japan where clouds spread, the temperature is high as warm air flows in. In Kyushu, there are many places where the temperature can reach around 30 degrees Celsius, making it feel hot and humid. It would be a good idea to choose clothes that are breathable.

In Hokkaido, the temperature rises slowly and it seems to be cool. Please be careful of the temperature difference from the previous day.

Today, the 19th (Tuesday), future weather: Cloudy and rainy in Okinawa and Hokkaido. The weather is also going downhill on the Pacific side of western Japan

2026/05/19 12:12

Today, the 19th (Tuesday), it will be mostly sunny during the day, but Hokkaido will be cloudy and rainy, and Okinawa is likely to experience a rainy season.
After the evening, there will be a lot of clouds in Kyushu and Shikoku, and there will be some places where it will rain.



Today, the 19th (Tuesday), the area around Honshu will be gently covered by high pressure. Hokkaido will be affected by moist air from the edge of the high pressure system.
Meanwhile, a front will extend near Okinawa, and this front will gradually move northward.




Hokkaido will be cloudy throughout the day, and it will likely rain mainly in northern Hokkaido.
There will be many places from Tohoku to the Chugoku region that will be widely sunny.
Shikoku and Kyushu are generally sunny until around noon, but after the evening it becomes cloudy or rainy in many places, so please prepare rain gear even if it's sunny when you go out.
In Okinawa, it rains easily in the main island and Daitojima region, and in some places it may rain heavily with thunder.


Maximum temperatures will continue to be higher than normal from Kyushu to Tohoku, and will reach around 30c in many places, especially inland.
It seems that there are places in western Japan where the temperature approaches 35c.
Also, in the Tohoku region, temperatures could rise to around 35 degrees Celsius in some areas, such as the Fukushima Basin, making it an extremely hot day.
The unseasonably hot weather continues in many places. You need to be careful about heatstroke.
Meanwhile, in Hokkaido, the temperature on the Sea of Japan side is lower than yesterday on the 18th, which is expected to be the normal temperature for this time of year.
Today in Okinawa, the weather is mostly normal, and it seems to be a little hot and humid.

This year's first 35c or higher (extremely hot day) was observed nationwide in Hita City, Oita Prefecture, and Toyooka City, Hyogo Prefecture.

2026/05/18 15:31

Today, the 18th, the area around Honshu is covered by a high-pressure system with summer characteristics, and it is sunny over a wide area, with strong sunlight shining down and temperatures rapidly rising.
As of 3:00 p.m., a maximum temperature of 35.3 C was observed in Hita City, Oita Prefecture, and Toyooka City, Hyogo Prefecture, marking the first extremely hot day (highest temperature of 35 C or higher) nationwide this year.


The unseasonably hot weather will continue tomorrow, so please be careful not to get heat stroke.

To prevent heatstroke, please keep the following points in mind.

(1) Avoid the heat as much as possible and drink water before you get thirsty. It is effective to wear clothes that are as cool as possible, and to use parasols and hats.
If you sweat a lot, don't forget to drink not only water but also salt.
(2) Don't put up with the heat even indoors, use the air conditioner to lower the indoor temperature to an appropriate level. It is a good idea to keep a thermometer in the room and check the room temperature frequently.
When ventilating the room, we recommend opening two places, such as windows and doors, or using an electric fan or ventilation fan.

If you feel even slightly unwell, it is important to take a rest and do not push yourself too hard.
Elderly people, children, and people with disabilities are especially susceptible to heatstroke, so please be careful and have those around you be attentive.

This year's first 35c or higher (extremely hot day) was observed nationwide in Hita City, Oita Prefecture, and Toyooka City, Hyogo Prefecture.

2026/05/18 15:30

Today, the 18th, the area around Honshu is covered by a high-pressure system with summer characteristics, and it is sunny over a wide area, with strong sunlight shining down and temperatures rapidly rising.
As of 3:00 p.m., a maximum temperature of 35.3 C was observed in Hita City, Oita Prefecture, and Toyooka City, Hyogo Prefecture, marking the first extremely hot day (highest temperature of 35 C or higher) nationwide this year.


The unseasonably hot weather will continue tomorrow, so please be careful not to get heat stroke.
To prevent heatstroke, please keep the following points in mind.

(1) Avoid the heat as much as possible and drink water before you get thirsty. It is effective to wear clothes that are as cool as possible, and to use parasols and hats.
If you sweat a lot, don't forget to drink not only water but also salt.
(2)Don't put up with the heat even indoors, use the air conditioner to lower the indoor temperature to an appropriate level. It is a good idea to keep a thermometer in the room and check the room temperature frequently.
When ventilating the room, we recommend opening two places, such as windows and doors, or using an electric fan or ventilation fan.
If you feel even slightly unwell, it is important to take a rest and do not push yourself too hard.
Elderly people, children, and people with disabilities are especially susceptible to heatstroke, so please be careful and have those around you be attentive.

Today's 18th and tomorrow 19th will continue to be hot ahead of the season - be careful of heatstroke

2026/05/18 11:57

Today, the 18th (Monday), the area around Japan will continue to be covered in high pressure, and it is expected to be sunny in many places. The sun is expected to reach a wide area, and maximum temperatures are expected to be higher than normal in many places. The early-season heat will continue until tomorrow, the 19th (Tuesday).





Today, the 18th (Monday), as of 11am, the highest temperature was 32.6c in Yonago, Yonago City, Tottori Prefecture, 31.9c in Dazaifu, Dazaifu City, Fukuoka Prefecture, and 31.7c in Kaga Nakatsuhara, Kaga City, Ishikawa Prefecture.

Today's predicted maximum temperature is expected to be similar to July-August temperatures in many places near Honshu. The temperature is expected to be 33c in Yamagata, 33c in Nagano, and 33c in Kofu, similar to August. Also, the temperature will be 34c in Kyoto and 34c in Kumamoto, just one step away from the hottest day.

This season's hot weather will continue until the 19th (Tuesday), and the day after the 20th (Wednesday), a front will extend to western Japan, clouds will spread, and there will be less sunlight, which will keep the temperature from rising.

Please be careful of heat stroke until tomorrow the 19th (Tuesday).
If you are working or exercising outdoors, please take precautions such as using a parasol or hat, drinking water and salt frequently, and taking breaks. Also, if you are spending your time indoors, don't overdo it and use your air conditioner properly.

Weather for the week: After unseasonable heat, there will be more cloudy and rainy days, and it looks like we will be at the beginning of the rainy season.

2026/05/18 07:25

From now on, after the early-season heat, there will be many cloudy and rainy days.



It will become sunny in many places around Honshu until the 19th (Tuesday). Temperatures are expected to be around 30 degrees Celsius in many areas, so it's important to take precautions against the heat to avoid heat stroke. The weather is likely to turn downhill in Shikoku, southern Kyushu, and Okinawa due to the effects of low pressure and fronts.

From around the 20th (Wednesday), it will be easier for fronts and low pressure systems to pass near Honshu. On the 20th (Wednesday), it will rain mainly in western Japan, and on the 21st (Thursday) it will likely spread to the Tohoku and Kanto regions. As the rain starts to fall, the temperature will drop significantly in some places from around the 21st (Thursday). The extreme heat that precedes the season seems to be calming down for now.

After that, cloudy and rainy days are expected to continue around Honshu. There will be more days when fronts and low pressure systems will pass near Honshu, and it will be the beginning of the rainy season from western to eastern Japan. Depending on the weather after that, the rainy season may be announced in some places.
It is better to prepare for heavy rain before the full-fledged rainy season begins.

The weather today, the 18th (Monday), is unseasonably hot with temperatures approaching 35 degrees Celsius or higher, so be careful of heatstroke.

2026/05/18 06:53

Today, the 18th (Monday), the area around Honshu will be widely covered by a belt-shaped high pressure system. Warm air with a temperature of over 15 degrees Celsius will flow approximately 1,500 meters above the mainland, and strong sunlight will reach the area during the day.

For this reason, temperatures will be around 30c in a wide area from Tohoku to Kyushu. Although it is not yet the start of full-fledged summer, there may be some places that record extremely hot days with temperatures of 35 degrees Celsius or higher. Toyooka City in Hyogo Prefecture is expected to experience an extremely hot day of 35 degrees Celsius, Hita City in Oita Prefecture is expected to experience an extremely hot day of 35 degrees Celsius, Kyoto and Saga are expected to experience 34 degrees Celsius, Fukushima and Nagano are expected to experience 33 degrees Celsius, and Nagoya and Osaka are expected to experience 31 degrees Celsius, making it unseasonably hot in some places.



At this time of year, your body is not yet accustomed to the heat, so the risk of heatstroke increases. Please take all possible precautions against heat stroke, such as hydrating frequently, taking breaks, and using the air conditioner without restraining yourself.

Clouds tend to spread in Hokkaido due to the influence of local fronts. In northern Hokkaido, there are likely to be some places where it will rain until late at night. If you will be returning home late, it may be a good idea to bring a folding umbrella.
In Okinawa, the atmospheric conditions are unstable due to the influence of cold air in the upper atmosphere, and there are likely to be some showers in the afternoon.

[Weekly Weather] Summer heat continues in the first half, rain gear comes in handy in the second half

2026/05/17 13:28

Over the weekend, a strong high-pressure system blanketed the area around Japan, making it unseasonably hot in many parts of the country. This high pressure system will gradually move away to the east of Japan through Tuesday. From now on, the weather is expected to be changeable as low pressure systems pass periodically.
A front will move east from the continent on Tuesday.
As a result, sluggish weather is expected mainly in western Japan from Tuesday to Wednesday. There is a possibility that another low pressure system will pass near Japan from Thursday to Saturday, and the weather is expected to deteriorate around Honshu.



Let's take a look at the latest weekly weather forecast.



Although clouds tend to spread over Hokkaido, there will be no major changes in the weather until the weekend, and the weather is expected to be relatively pleasant and sunny.

From Monday to Tuesday, the weather is clear and the sun shines brightly from eastern to western Japan, and the temperature rises rapidly. It's midsummer day in many places, with maximum temperatures around 30 degrees Celsius, so it's likely to be the start of a week in which the unseasonably hot weather will hit your body. When going out, please take strict precautions against heatstroke, such as hydrating frequently and choosing appropriate clothing.

On the other hand, in the second half of the week, the high pressure system will gradually move away to the east, and the weather will deteriorate near Honshu due to the influence of the front. As moist air tends to flow towards the front, there is a possibility that the rain may become heavier locally.
It's safe to carry a folding umbrella when you go out.
Before heading out, be sure to check the latest weather information.