Okinawa Main Island/Daito Region: Risk of lightning strikes, gusts of wind, and warning-level heavy rain into tomorrow

2026/05/23 12:45

Atmospheric conditions in the Okinawa main island region and Daitojima region are extremely unstable due to the influence of the front. Currently, there are active rain clouds and lightning has been observed in various places.
In Izena, Izena Village, Shimajiri District, Okinawa Prefecture, heavy rain exceeding 40mm per hour was observed this morning.



Unstable conditions are expected to continue due to the rainy season front and moist air flowing into the front. Please be careful of strong wind gusts such as lightning and tornadoes through the 24th.

[Rain Forecast]
1-hour precipitation expected on the 23rd
Okinawa Main Island region 40mm (in areas with the most)
Forecasted from 12:00 on the 23rd to 12:00 on the 24th 24-hour precipitation
Okinawa Main Island Region 80 mm (most places)

In the Okinawa Main Island Region, there is a risk of warning-level heavy rain on the 23rd depending on the development of rain clouds. Be wary of landslides, flooding of low-lying areas, and rising river waters.



Additionally, the front is expected to remain nearby until the 24th. If there are signs that a cumulonimbus cloud is approaching (suddenly darkening sky, thunder, cold wind, etc.), please take precautions such as moving inside a building.

Today's 23rd (Saturday) Afternoon Weather Warning of showers in places from western to eastern Japan

2026/05/23 12:31

Today, the 23rd, clouds will continue to spread over western and eastern Japan in the afternoon, and it will rain in places. In Kyushu, there are places in midsummer where the maximum temperature is over 30 degrees Celsius, while on the Pacific side of Kanto and Tohoku the air is likely to remain cool, although not as cold as yesterday.
Today, the afternoon of the 23rd, we will continue to be affected by humid air, mainly on the Pacific side.





Looking at the weather forecast for this afternoon, it looks like it will rain intermittently in Okinawa. Please be aware that there is a possibility of heavy rain in the Okinawa main island region into the evening.
The sunlight is likely to reach Kyushu mainly in the northern part. It rains easily in Shikoku and the Chugoku region, and there are likely to be some places where the rain can be heavy at times. There will be a lot of clouds in the Kinki, Tokai, and Kanto-Koshin regions, and it will rain in places from the evening onwards. Clouds are gradually spreading in Hokuriku, and there are likely to be some places with showers. Clouds will gradually increase in northern Japan, but there doesn't seem to be any major change in the weather.


The highest temperature in the afternoon will be the same or higher than the previous day in many places. In Hita City, Oita Prefecture, the temperature is 31 degrees Celsius, and in Kumamoto, it is 30 degrees Celsius, so there are places in Kyushu where it is midsummer, so it is necessary to take precautions against heat stroke. Make sure to drink plenty of water and wear well-ventilated clothing.

The Pacific side of the Kanto and Tohoku regions will be broadly at the same level as April, although it will be higher than the previous day. The wind is blowing from the east, making it feel cooler than the actual temperature. You will also need something to wear during the day.

There are many sunny days due to the predominance of high pressure, and there is a tendency for little rain nationwide.On the other hand, there are some places where there is heavy rain locally due to the influence of cold air in the upper atmosphere (weather summary from May 10, 2026 to May 16, 2026)

2026/05/23 07:34

This is a summary of the weather for this period (May 10th to May 16th, 2026).

#Summary of the weather for this period (May 10th to May 16th)
The average temperature was above normal in many regions due to the high pressure and many sunny days, and in northern Japan, there were places that were well above normal due to the warm air. In Okinawa/Amami, there were many cloudy and rainy days due to the influence of the rainy season front, so temperatures tended to be slightly below normal.

Although there were localized heavy rains from around the 12th to the 14th due to the influence of cold air in the upper atmosphere, there were many sunny days throughout the period, and precipitation was well below normal over a wide area. Okinawa, the Izu Islands, and the Ogasawara Islands exceeded normal levels due to the influence of the rainy season front, and the Ogasawara Islands experienced total precipitation that was about six times the normal year.

Sunshine hours were much higher than normal in many places from Hokkaido to Kyushu because there were many sunny days covered by high pressure. Okinawa and the Ogasawara Islands had many cloudy and rainy days due to the influence of the rainy season front, so temperatures tended to be well below normal.



[About this period's weather]
#Characteristics of pressure distribution
On the 10th, the area around Honshu was widely covered by high pressure. The rainy season front has stalled in the south of Honshu. Typhoon No. 5 turned into a tropical cyclone east of the Philippines. On the 11th, the center of the high pressure system moved away from the sea east of Japan. The seasonal rain front remained stationary south of Honshu. On the 12th, the area around Honshu continued to be within the area of high pressure moving over the sea east of Japan. A low pressure system has formed over the southern front of Honshu. Multiple low pressure systems have formed in the East China Sea and are moving southeast. On the 13th, the low pressure system moving near Okinawa became unclear, and an high pressure system formed near the Yellow Sea. The rainy season front gradually moved southward. On the 14th, the area around Honshu, from Hokkaido to the Nansei Islands, was widely covered by a high-pressure system centered over the Sea of Okhotsk and the Sea of Japan, and the seasonal rain front was stationary in the south of Japan. On the 15th, high pressure continued to cover a wide area around Japan, and the Baiu front remained stationary in the south of Japan. On the 16th, high pressure continued to cover a large area around Honshu, but a low pressure system that formed near northeastern China late on the night of the 15th moved slowly from near Sakhalin to the Sea of Okhotsk.

#Precipitation
On the 10th, rain clouds stagnated in Okinawa and the Ogasawara Islands due to the influence of the seasonal rain front, resulting in rain and thunderstorms. Heavy rain was observed on Chichijima Island in the Ogasawara Islands, with an hourly rainfall of 24.5 mm. On the 11th, rain fell mainly in Okinawa and the Ogasawara Islands due to the influence of the front. In Okinawa, heavy rain with an hourly rainfall of 37.5 mm was observed at Nakasuji in the Sakishima Islands. On the 12th, localized rain and thunderstorms occurred mainly in inland areas from Tohoku to Kyushu due to the effect of low atmospheric pressure and moist air accompanied by cold air. Heavy rain with an hourly rainfall of 27.5 mm in Ikkchi, Harima Village, Kumamoto Prefecture. On the 13th, atmospheric conditions became unstable from Tohoku to Kyushu due to cold air in the sky. Localized rain and thunderstorms mainly in inland areas and along mountains. On the 14th, localized rain and thunderstorms occurred mainly in inland areas from Tohoku to Kyushu due to cold air in the sky and rising temperatures during the day. In Kanagawa Prefecture, heavy rain warnings were temporarily announced in Yokohama and Fujisawa. On the 15th, due to active rain clouds, heavy rain was observed on Yonaguni Island in the morning, with an hourly rainfall of 46.5 mm. The effects of the cold air weakened around Honshu, and many places experienced stable skies through the 16th.

#Temperature
On the 10th, the temperature was around 25c in a wide area around Honshu. In Tokyo, the temperature rose to 24.8c, the same level as early June. In Tomakomai, Hokkaido, the temperature rose to 23.9c, exceeding the hottest period. On the 11th, with the exception of Okinawa and Ogasawara, the area around Honshu was largely sunny and temperatures were rising. In Hita City, Oita Prefecture, the temperature rose to 28.7c, making it a summer day. On the 12th, temperatures rose widely around Honshu within an area of high pressure. In eastern Hokkaido, temperatures rose due to the Fohn phenomenon, with a temperature of 29.1c observed in Bihoro. The temperature was higher than that of Okinawa. On the 13th, the area around Honshu became clear in the morning, and a summer day was observed over a wide area. In Tajimi City, Gifu Prefecture, the temperature has risen to 29.5 degrees Celsius, just one step away from midsummer. On the 14th, temperatures rose mainly in western and eastern Japan, and in western Japan, Kumamoto, Saga, and Yamaguchi prefectures recorded midsummer days, and in Kakoku, Kumamoto Prefecture, the temperature rose to 31.6c. On the 15th, warmer air than the previous day flowed into the sky, causing temperatures to rise even in northern Japan. 29.6c was recorded in Bihoro, Hokkaido. On the 16th, the above-average heat continued, with a temperature of 32.6c observed in Kake, Hiroshima Prefecture. Midsummer day observation points totaled 40 points.

Weekly Forecast: Temperatures will be high nationwide at the beginning of the week, making it susceptible to fronts and low pressure systems.

2026/05/23 07:15

From now on, the temperature will be around 30c in many places at the beginning of the week. From (Tuesday) onwards, there will be a relatively high number of cloudy and rainy days, and the humid and humid days are likely to continue.



Tomorrow, the 24th (Sun), clouds will spread easily in western and eastern Japan, resulting in an unrefreshing sky. There is a possibility of showers along the coast, so it would be a good idea to bring a foldable umbrella when going out. In northern Japan and the Hokuriku region, there will be places with rain and thunderstorms due to the influence of local fronts. In the Tohoku Pacific side and the Kanto region, the influence of cold northeast winds will weaken, and temperatures are likely to be around normal.

The beginning of the week on the 25th (Monday) will be covered by a wide area of high pressure, and the weather will be on the mend. However, temperatures are expected to rise mainly in inland areas, with some places experiencing daytime maximum temperatures of 30 C or higher.

On the 26th (Tuesday), a low pressure system and front will approach from the west. The weather will turn downward in western Japan, and from the 27th (Wednesday) to the 28th (Thursday), the weather will be widely unstable due to the influence of fronts and low pressure. On the Sea of Japan side, the isobars around the low pressure area are expected to narrow and the winds are expected to become stronger, so it is necessary to be careful about strong winds and high waves at sea.

After the 26th (Tuesday), there will be many cloudy and rainy days in western and eastern Japan, and the temperature will be high, making it feel damp. It is expected that we will gradually approach the rainy season. Additionally, a low pressure system believed to be a tropical storm is expected to approach Japan around the end of this month, which could have a major impact on the weather around Honshu.

At present, there is a wide range of predictions regarding the trends of fronts and low pressure systems, and there is a great deal of uncertainty, but please pay attention to the latest weather information that will be updated in the future. It would be a good idea to proceed in stages, such as cleaning gutters and preparing stockpiles for disasters, before the full-fledged rainy season begins.

Weather on Saturday and Sunday: Rainy skies in Okinawa; sunshine in some places in Kyushu and northern Japan on Saturday

2026/05/22 14:47

This weekend, there will be periods of sunshine in Kyushu and northern Japan tomorrow, the 23rd (Saturday), but the weather will not be clear on the Pacific side of western and eastern Japan. On the 24th (Sunday), clouds will spread across the country, and many places will experience rain. Okinawa/Amami will continue to experience rainy weather due to the rainy season front.



Sunshine is expected to reach northern Japan, Hokuriku, and Kyushu on Saturday the 23rd. It's best to do your laundry on Saturday.
From the Kanto region to Chugoku and Shikoku, clouds will spread easily and the weather will not be refreshing. It is expected to gradually rain in some places from the afternoon. Even if it's not raining when you go out, it's a good idea to bring a foldable umbrella with you.

From the night of the 23rd (Saturday) to the 24th (Sunday), a low pressure system will form in the Sea of Japan and move northeast, and a low pressure system will also form on the front south of Japan and is expected to move eastward.
On the 24th (Sunday), clouds are likely to spread across the country, and it is expected to rain in many places. There will be places where it will rain, mainly from northern Japan to Hokuriku, and from Kanto to Kyushu on the Pacific side.

Okinawa is expected to continue experiencing rainy weather due to the front and moist air flowing into it.
Especially in the main island of Okinawa, heavy rain accompanied by thunder is expected to occur in places from today, the 22nd (Friday) to the 23rd (Saturday). Depending on the degree of rain cloud development, there is a risk of heavy rain reaching warning level.
Please be careful of landslides, flooding of low-lying areas, rising river waters, lightning strikes, and gusts of wind.





The predicted maximum temperature will be lower than normal on the Pacific side of northern and eastern Japan tomorrow, the 23rd (Saturday), and it will continue to feel cool. In Tokyo, the temperature will be 20c, similar to mid-April. Please adjust it properly with your jacket. On the other hand, the Sea of Japan coast of northern and eastern Japan, as well as western Japan, will experience near-normal or higher-than-normal conditions.
On the 24th (Sunday), temperatures in some parts of Kyushu are expected to be similar to July. In Kagoshima, it is expected to be a midsummer day with temperatures reaching 30 degrees Celsius. Even on days with little sunlight, take precautions against heatstroke.

Weather for today, the 22nd (Friday): The weather is improving in western Japan, and the sky is likely to rain in the Kanto region until around noon.

2026/05/22 06:48

Today, the 22nd (Friday), the sky looks like it will be rainy mainly in Tohoku and eastern Japan due to the effects of low pressure and fronts. Meanwhile, in western Japan, the weather is improving and the sunshine is likely to return.



There will be periods of cloud cover in Hokkaido, but it will mostly be sunny. The weather isn't bad and it looks like we can hang our laundry outside to dry.
There are still some places in the northern Tohoku region where the rain will remain until the morning, but the sunshine will gradually return.

The southern Tohoku region, Kanto region, and Hokuriku region will experience rainy weather until around noon due to the effects of low pressure and fronts. Please bring rain gear when going out.

Although there will be some lingering rain in the Tokai region and western Japan in the morning, the weather is improving. There will be places in Kyushu and Shikoku where the sun will return in the afternoon.

It looks like the rainy season will return to Okinawa and it will be a rainy day. Please be careful of lightning strikes and gusts of wind, as there is a risk of the storm becoming stronger with thunder.

Temperatures will not rise on the Pacific coast north of Kanto, where cold winds blow from the northeast, and in central Tokyo it is expected to reach 18 C, 5 C lower than the previous day (21st). The temperature will be similar to early April, and there will be a big difference in temperature from the previous day, so please be careful when choosing your clothes.
In western Japan, the sun will reach some places in the afternoon, and temperatures are expected to rise to around 30 degrees Celsius, mainly on the Pacific side. Please take precautions against heatstroke when participating in outdoor activities.
Northern Japan is likely to experience temperatures typical of this time of year.

[Ocean Summary] Sea surface temperature in the Sea of Japan is 4c higher than normal (May 10th to 16th, 2026)

2026/05/21 16:56

Due to the effects of the low pressure system, waves were as high as 4 meters in the far east of Japan.
Sea surface temperatures in the Japanese waters expanded to areas where the sea surface temperature was significantly higher than normal in the central and western regions, and was up to 4 C higher on the continental side.
Below is a summary of the ocean (May 10-16, 2026)



#Pressure distribution and waves
On the 10th, the low pressure system that had been located east of Hokkaido the day before moved northeast to the east of Kuril Islands.
In the far east of Japan, the wave height was 4m and it became a storm.
On the 11th, a low pressure system moved northeast near Sakhalin.
This effect increased the gradient of atmospheric pressure, resulting in wave heights of 3 meters in the west of Hokkaido.
From the 10th to the 13th, the front stalled south of Japan and gradually moved eastward.
The waves became high from the Nansei Islands to the Ogasawara Islands when the front hit.
From the 14th to the 15th, the area around Honshu was covered with high pressure, and the waves in the Japanese waters were calm.
On the 16th, waves were somewhat high in the waters near the Nansei Islands due to the influence of a stationary front south of Japan.



#Sea surface temperature
Sea surface temperatures in the Japanese sea area expanded to areas where areas were significantly higher than normal in the central and western regions, and were up to 4 C higher on the continental side.
In the East China Sea, areas with higher than normal temperatures expanded and were up to 3 C warmer.
The waters near the Nansei Islands remained at normal levels, while the waters south of Japan continued to be slightly higher than normal.
Continuing, the sea off the coast of the Tokai region was slightly lower than normal, and the area east of the Kanto region was higher than normal, expanding by up to 4 C.
Off the coast of Sanriku, the sea area continued to be much lower than normal, with temperatures as low as 4c
.
The waters near the Kuril Islands and the Sea of Okhotsk continued to be at normal levels.

Weekly weather: Many cloudy and rainy days mainly on the Pacific side; the heat will return at the beginning of the week

2026/05/21 08:03

From now on, the area around Honshu is likely to be affected by fronts and low pressure systems, so it is likely that there will be many cloudy and rainy days. Please take care of your health as the temperature difference tends to be large.



Tomorrow, the 22nd (Friday), the low pressure system above the front will move away to the east of Japan, and the weather will start to improve in western Japan. However, persistent rain clouds will remain in eastern Japan and Tohoku, and there will be places where it will rain intermittently. Due to the effects of low pressure and fronts, the spacing between isobar lines becomes narrower, so you need to be careful of strong winds and high waves in coastal areas.

On Saturday and Sunday, the weekend of the 23rd and 24th, there will be some places in northern Japan and Hokuriku where the sun will reach, but from eastern to western Japan, it is expected to be cloudy and rainy in many places, especially on the Pacific side. On the Pacific side of northern and eastern Japan, the extreme heat tends to subside for a while due to the influence of cool easterly winds, but it is likely to get hot again at the beginning of the week.

On the 25th (Monday), the front and low pressure system will move south of Honshu, and more areas will be exposed to sunlight. Temperatures will rise mainly in inland areas, with midsummer days reaching over 30c in some places. Please be careful of heat stroke.
A new front and low pressure system are expected to move in from the west around the 26th (Tuesday), and the front is expected to remain near western and eastern Japan on the 27th (Wednesday). It will rain over a wide area and the temperature will be high, so it will be humid and uncomfortable.

3-month forecast: High temperatures are trending nationwide even before summer officially begins. Be careful of heavy rain disasters during the rainy season.

2026/05/20 20:42

On the 19th (Tuesday), the Japan Meteorological Agency announced the latest 3-month forecast, which shows the weather outlook for the next 3 months.



There is a high probability that an El Nino phenomenon will occur in the future, and sea surface temperatures will be high in the eastern to central equatorial Pacific Ocean and also in the central tropical North Pacific region.
Also, due to the strong westerly winds of the monsoon, cumulonimbus clouds are expected to form frequently from the east of the Philippines to the central Pacific Ocean. On the other hand, there will be fewer cumulonimbus clouds from around Indonesia to the Indian Ocean.

As a result of these effects, upper-level westerly winds are expected to flow southerly than normal over the Eurasian continent, but are expected to flow slightly northerly than normal from the vicinity of Japan to the sea east of Japan. The extent of the Tibetan high near Japan will be similar to normal, the extent of the Pacific high to the north will be stronger than normal, and the extent to the south of Japan will be weaker.

From the above, it is expected that the area around Japan will be easily covered with warm air.



The average temperature for three months is expected to be higher than normal nationwide from Hokkaido to Okinawa. Temperatures were already high even before the start of full-fledged summer, and there were some locations where extremely hot days were observed in mid-May. The full-fledged rainy season begins around June, and with the high humidity and high temperatures, it is important to be careful about heat stroke.
There is a possibility that this summer will be the hottest on record, and some areas may record "extremely hot days" with maximum temperatures of 40 degrees Celsius or higher. Please take measures against the heat, such as hydrating frequently and using appropriate air conditioning.



The average precipitation for three months is expected to be similar to normal, but the rainy season is the period of the year with the highest precipitation. At the end of the rainy season, warm, humid air flows toward the rainy season front, causing heavy rain and is expected to increase the likelihood of heavy rain disasters.
Let's prepare as much as possible for heavy rain disasters before the full-fledged rainy season begins, such as checking dangerous places and evacuation routes around your home on a hazard map, and making sure you have enough drinking water and food for emergencies.

[General weather information] Be careful of lightning, gusts of wind, and sudden strong rain from Konya to tomorrow, the 21st (Thursday)

2026/05/20 19:08

The Japan Meteorological Agency is currently issuing general weather information regarding lightning and gusts.

In western and eastern Japan, please be careful of thunderstorms, tornadoes, strong gusts of wind, and sudden heavy rain from now until tomorrow the 21st.




A front is extending from central China to western Japan, and tomorrow, the 21st (Thursday), it will extend to eastern Japan, and the low pressure will move eastward through the Sea of Japan. As warm, humid air flows toward the front, atmospheric conditions will be unstable in western and eastern Japan on the 21st.



Western and eastern Japan should be on guard against lightning, tornadoes, severe gusts, and sudden heavy rain on the 21st. There may also be heavy rain in some places.
If there are signs of a developing cumulonimbus cloud approaching, please take every precaution to ensure your safety, such as moving inside a building.