Expanding Target from Typhoons to Linear Rainbands, Initiating Water Vapor Observation in the East China Sea
Key facts
- Expanding Target from Typhoons to Linear Rainbands, Initiating Water Vapor Observation in the East China Sea
- NTT and OIST, in collaboration with the Meteorological Research Institute, have begun observing water vapor in the East China Sea to improve the prediction accuracy of typhoons and linear rainbands. In FY2025, they conducted typhoon observations around the Okinawa islands and confirmed potential advancements. In FY2026, they will expand the observation area to the East China Sea to elucidate the formation and development mechanisms of linear rainbands and enhance prediction accuracy.
- Source: PR Times
- Date: June 12, 2026
Direct answer
NTT and OIST, in collaboration with the Meteorological Research Institute, have begun observing water vapor in the East China Sea to improve the prediction accuracy of typhoons and linear rainbands. In FY2025, they conducted typhoon observations around the Okinawa islands and confirmed potential advancements. In FY2026, they will expand the observation area to the East China Sea to elucidate the formation and development mechanisms of linear rainbands and enhance prediction accuracy.
- Citation
- Expanding Target from Typhoons to Linear Rainbands, Initiating Water Vapor Observation in the East China Sea (June 12, 2026), PR Times
- Source
- PR Times
- Date
- June 12, 2026
NTT and OIST, in collaboration with the Meteorological Research Institute, have begun observing water vapor in the East China Sea to improve the prediction accuracy of typhoons and linear rainbands. In FY2025, they conducted typhoon observations around the Okinawa islands and confirmed potential advancements. In FY2026, they will expand the observation area to the East China Sea to elucidate the formation and development mechanisms of linear rainbands and enhance prediction accuracy.
📋 Article Processing Timeline
- 📰 Published: June 12, 2026 at 00:04
- 🔍 Collected: June 11, 2026 at 15:21
- 🤖 AI Analyzed: June 12, 2026 at 18:15 (26h 54m after Collected)
Key Announcement Points:
From June to September 2025, atmospheric and oceanic observations were conducted by approaching multiple typhoons using autonomous marine observation equipment and buoys in the sea areas around the Okinawa islands. The acquired observational data confirmed the potential to improve typhoon intensity forecasts and sea surface temperature data.
Based on the track record of typhoon observations around the Okinawa islands, this year, in addition to typhoon observations, the observation area will be expanded to the East China Sea. By observing water vapor over the sea, changes in water vapor flowing into the Kyushu region will be captured early, accelerating research to elucidate the formation and development processes of linear rainbands and improve prediction accuracy.
NTT Corporation (Headquarters: Chiyoda-ku, Tokyo; President and CEO: Akira Shimada; hereinafter referred to as "NTT") and the Okinawa Institute of Science and Technology Graduate University (Onna Village, Kunigami District, Okinawa Prefecture; Interim President and CEO: Daniel Jeffries; hereinafter referred to as "OIST") entered into a joint research agreement with the Meteorological Research Institute (Tsukuba City, Ibaraki Prefecture; hereinafter referred to as "MRI") in May 2025.
NTT and OIST, in collaboration with MRI, conducted atmospheric and oceanic observations by approaching multiple typhoons using autonomous marine observation equipment and buoys in the sea areas around the Okinawa islands. Data confirming changes in atmospheric pressure, wind speed, and sea surface temperature were acquired, confirming the potential to improve the accuracy of typhoon intensity forecasts and sea surface temperature data. In FY2026, in addition to typhoon observations, the observation area will be expanded to the East China Sea, and efforts will be made to elucidate the formation and development processes of linear rainbands. By capturing changes in water vapor over the sea, we aim to achieve early prediction of linear rainbands.
1. Background
In May 2025, to clarify the role of the ocean in the formation and development of extreme weather phenomena and to grasp the reality and elucidate the mechanisms of remarkable phenomena such as linear rainbands and heavy rainfall associated with typhoons, NTT and OIST, possessing typhoon observation technology and track record in marine environments, entered into a joint research agreement with MRI, which has expertise in extreme weather※1. Current meteorological satellite remote sensing alone makes it difficult to capture data on sea surface weather and ocean surface layers related to the formation and development of typhoons and linear rainbands directly above them. Therefore, observational research to elucidate atmospheric-oceanic mechanisms has commenced. This joint research is entering its second year※2, and field observations using autonomously navigating unmanned marine observation vehicles and buoys will be further expanded for collecting data on sea surface weather and ocean surface layers in typhoon-affected areas during the rainy season※3.
Figure 1: Image of the Initiative
Figure 2: Schedule
2. FY2025 Achievements
From June to September 2025, atmospheric and oceanic observations were conducted in the sea areas around the Okinawa islands. Observations were made by approaching Typhoons No. 7 and No. 8 using autonomous marine observation equipment, and data for Typhoons No. 12 and No. 23 were acquired by buoys.
From the observational data at the sea surface, rapid drops in atmospheric pressure, increases in wind speed, and changes in wind direction associated with typhoon approaches were confirmed (Figure 3). In particular, changes in sea surface temperature before and after typhoon passage, which affect typhoon development and decay, were captured.
Furthermore, MRI has been developing the environment for prediction experiments utilizing the observational data acquired through the joint research and has begun preliminary experiments. In experiments predicting typhoon intensity, experiments were conducted using predicted values of sea surface temperature and stored heat within the ocean from an ocean prediction system that utilizes ocean observation data, etc. By reflecting the impact of sea surface temperature drops associated with typhoon passage, cases where the prediction accuracy of typhoon maximum wind speed improved were confirmed.
Thus, through the utilization of observational data, the potential to improve the accuracy of sea surface temperature data and enhance typhoon intensity forecasting has been confirmed. Moving forward, research utilizing observational data will continue to elucidate the interaction between the atmosphere and the ocean via the sea surface.
Figure 3: Observation Results of Typhoon No. 23 by Buoy (Top: Trajectory of Typhoon and Buoy, Bottom: Observational Data)
*Graph provided by the Meteorological Research Institute
3. Details of the Initiative
A linear rainband is a phenomenon where developed rain clouds form a band, causing heavy rainfall in the same location for an extended period. Heavy rainfall caused by linear rainbands is related to a large amount of water vapor flowing in from the sea. It is known that warm, moist air flows from the East China Sea into the Kyushu region, particularly for linear rainbands that occur there. Therefore, in FY2026, the observation range will be expanded to the East China Sea to directly observe water vapor over the sea. Detailed observational data on water vapor over the sea is scarce, which is one of the challenges in improving the prediction accuracy of linear rainbands. This observation is expected to be a new initiative to compensate for this data shortage.
Therefore, based on the achievements of FY2025, the following will be undertaken in FY2026:
Newly conduct linear rainband observations in the East China Sea, analyze the amount of water vapor flowing into the Kyushu area, and work to elucidate the formation process of linear rainbands and improve rainfall prediction accuracy (Figure 4).
Continue typhoon observations in the sea areas around the Okinawa islands, analyze observational data around and along the typhoon's path, and aim to improve the prediction accuracy of typhoon intensity and track by elucidating the formation and development processes of typhoons (Figure 5).
Figure 4: Overview of Linear Rainband Observation in FY2026 Figure 5: Overview of Typhoon Observation in FY2026
(Created by processing maps from the Geospatial Information Authority of Japan)
4. Future Development
Through joint research with MRI, NTT and OIST will directly collect data on sea surface weather and ocean surface layers in marine areas to elucidate the formation and development processes of extreme weather phenomena such as linear rainbands and typhoons. These data will be utilized to contribute to the understanding of atmospheric-oceanic mechanisms. Furthermore, by grasping the spatial structure (high-resolution distribution) of water vapor inflow, which is a cause of linear rainbands, we will improve the prediction accuracy of linear rainbands and typhoons. This is expected to contribute to a society where municipalities and residents can take early evacuation and disaster prevention measures.
NTT is also promoting the demonstration of low-cost observation technology that combines balloons with Low Power Wide Area (LPWA) wireless communication (Figure 6). If meteorological data can be acquired in the upper atmosphere over the sea, it may be possible to obtain detailed information on the state of the atmosphere above the sea, which has been difficult to observe until now.
Figure 6: Image of NTT's Independent Observation Technology Demonstration
At OIST, by bringing together experts and researchers from diverse fields such as meteorology, oceanography, mathematical sciences, and data science, and by fusing their specialized knowledge and cutting-edge research findings, interdisciplinary research will be promoted to deepen scientific understanding of the interaction between the ocean and the atmosphere.
In the future, aiming to realize an indispensable marine observation platform for Japan, an island nation, research and development will be advanced to improve the accuracy of extreme weather prediction.
[Glossary]
※1. June 3, 2025, "NTT and OIST Commence Joint Research with Meteorological Research Institute to Elucidate Mechanisms of Linear Rainbands and Typhoons"
https://group.ntt/jp/newsrelease/2025/06/03/250603a.html
※2. FY2026 Meteorological Research Institute Press Release
https://www.mri-jma.go.jp/Topics/R08/080605/080605_press.html
※3. Rainy season refers to the period when river water levels tend to rise due to rainfall, snowmelt, etc.
From June to September 2025, atmospheric and oceanic observations were conducted by approaching multiple typhoons using autonomous marine observation equipment and buoys in the sea areas around the Okinawa islands. The acquired observational data confirmed the potential to improve typhoon intensity forecasts and sea surface temperature data.
Based on the track record of typhoon observations around the Okinawa islands, this year, in addition to typhoon observations, the observation area will be expanded to the East China Sea. By observing water vapor over the sea, changes in water vapor flowing into the Kyushu region will be captured early, accelerating research to elucidate the formation and development processes of linear rainbands and improve prediction accuracy.
NTT Corporation (Headquarters: Chiyoda-ku, Tokyo; President and CEO: Akira Shimada; hereinafter referred to as "NTT") and the Okinawa Institute of Science and Technology Graduate University (Onna Village, Kunigami District, Okinawa Prefecture; Interim President and CEO: Daniel Jeffries; hereinafter referred to as "OIST") entered into a joint research agreement with the Meteorological Research Institute (Tsukuba City, Ibaraki Prefecture; hereinafter referred to as "MRI") in May 2025.
NTT and OIST, in collaboration with MRI, conducted atmospheric and oceanic observations by approaching multiple typhoons using autonomous marine observation equipment and buoys in the sea areas around the Okinawa islands. Data confirming changes in atmospheric pressure, wind speed, and sea surface temperature were acquired, confirming the potential to improve the accuracy of typhoon intensity forecasts and sea surface temperature data. In FY2026, in addition to typhoon observations, the observation area will be expanded to the East China Sea, and efforts will be made to elucidate the formation and development processes of linear rainbands. By capturing changes in water vapor over the sea, we aim to achieve early prediction of linear rainbands.
1. Background
In May 2025, to clarify the role of the ocean in the formation and development of extreme weather phenomena and to grasp the reality and elucidate the mechanisms of remarkable phenomena such as linear rainbands and heavy rainfall associated with typhoons, NTT and OIST, possessing typhoon observation technology and track record in marine environments, entered into a joint research agreement with MRI, which has expertise in extreme weather※1. Current meteorological satellite remote sensing alone makes it difficult to capture data on sea surface weather and ocean surface layers related to the formation and development of typhoons and linear rainbands directly above them. Therefore, observational research to elucidate atmospheric-oceanic mechanisms has commenced. This joint research is entering its second year※2, and field observations using autonomously navigating unmanned marine observation vehicles and buoys will be further expanded for collecting data on sea surface weather and ocean surface layers in typhoon-affected areas during the rainy season※3.
Figure 1: Image of the Initiative
Figure 2: Schedule
2. FY2025 Achievements
From June to September 2025, atmospheric and oceanic observations were conducted in the sea areas around the Okinawa islands. Observations were made by approaching Typhoons No. 7 and No. 8 using autonomous marine observation equipment, and data for Typhoons No. 12 and No. 23 were acquired by buoys.
From the observational data at the sea surface, rapid drops in atmospheric pressure, increases in wind speed, and changes in wind direction associated with typhoon approaches were confirmed (Figure 3). In particular, changes in sea surface temperature before and after typhoon passage, which affect typhoon development and decay, were captured.
Furthermore, MRI has been developing the environment for prediction experiments utilizing the observational data acquired through the joint research and has begun preliminary experiments. In experiments predicting typhoon intensity, experiments were conducted using predicted values of sea surface temperature and stored heat within the ocean from an ocean prediction system that utilizes ocean observation data, etc. By reflecting the impact of sea surface temperature drops associated with typhoon passage, cases where the prediction accuracy of typhoon maximum wind speed improved were confirmed.
Thus, through the utilization of observational data, the potential to improve the accuracy of sea surface temperature data and enhance typhoon intensity forecasting has been confirmed. Moving forward, research utilizing observational data will continue to elucidate the interaction between the atmosphere and the ocean via the sea surface.
Figure 3: Observation Results of Typhoon No. 23 by Buoy (Top: Trajectory of Typhoon and Buoy, Bottom: Observational Data)
*Graph provided by the Meteorological Research Institute
3. Details of the Initiative
A linear rainband is a phenomenon where developed rain clouds form a band, causing heavy rainfall in the same location for an extended period. Heavy rainfall caused by linear rainbands is related to a large amount of water vapor flowing in from the sea. It is known that warm, moist air flows from the East China Sea into the Kyushu region, particularly for linear rainbands that occur there. Therefore, in FY2026, the observation range will be expanded to the East China Sea to directly observe water vapor over the sea. Detailed observational data on water vapor over the sea is scarce, which is one of the challenges in improving the prediction accuracy of linear rainbands. This observation is expected to be a new initiative to compensate for this data shortage.
Therefore, based on the achievements of FY2025, the following will be undertaken in FY2026:
Newly conduct linear rainband observations in the East China Sea, analyze the amount of water vapor flowing into the Kyushu area, and work to elucidate the formation process of linear rainbands and improve rainfall prediction accuracy (Figure 4).
Continue typhoon observations in the sea areas around the Okinawa islands, analyze observational data around and along the typhoon's path, and aim to improve the prediction accuracy of typhoon intensity and track by elucidating the formation and development processes of typhoons (Figure 5).
Figure 4: Overview of Linear Rainband Observation in FY2026 Figure 5: Overview of Typhoon Observation in FY2026
(Created by processing maps from the Geospatial Information Authority of Japan)
4. Future Development
Through joint research with MRI, NTT and OIST will directly collect data on sea surface weather and ocean surface layers in marine areas to elucidate the formation and development processes of extreme weather phenomena such as linear rainbands and typhoons. These data will be utilized to contribute to the understanding of atmospheric-oceanic mechanisms. Furthermore, by grasping the spatial structure (high-resolution distribution) of water vapor inflow, which is a cause of linear rainbands, we will improve the prediction accuracy of linear rainbands and typhoons. This is expected to contribute to a society where municipalities and residents can take early evacuation and disaster prevention measures.
NTT is also promoting the demonstration of low-cost observation technology that combines balloons with Low Power Wide Area (LPWA) wireless communication (Figure 6). If meteorological data can be acquired in the upper atmosphere over the sea, it may be possible to obtain detailed information on the state of the atmosphere above the sea, which has been difficult to observe until now.
Figure 6: Image of NTT's Independent Observation Technology Demonstration
At OIST, by bringing together experts and researchers from diverse fields such as meteorology, oceanography, mathematical sciences, and data science, and by fusing their specialized knowledge and cutting-edge research findings, interdisciplinary research will be promoted to deepen scientific understanding of the interaction between the ocean and the atmosphere.
In the future, aiming to realize an indispensable marine observation platform for Japan, an island nation, research and development will be advanced to improve the accuracy of extreme weather prediction.
[Glossary]
※1. June 3, 2025, "NTT and OIST Commence Joint Research with Meteorological Research Institute to Elucidate Mechanisms of Linear Rainbands and Typhoons"
https://group.ntt/jp/newsrelease/2025/06/03/250603a.html
※2. FY2026 Meteorological Research Institute Press Release
https://www.mri-jma.go.jp/Topics/R08/080605/080605_press.html
※3. Rainy season refers to the period when river water levels tend to rise due to rainfall, snowmelt, etc.
FAQ
How does this research contribute to the prediction of linear rainbands?
By observing water vapor in the East China Sea, it captures the inflow of water vapor into the Kyushu region early, contributing to the elucidation of formation/development mechanisms and improved prediction accuracy of linear rainbands.
What roles do NTT and OIST play?
NTT provides observation technology, while OIST brings together expertise from researchers in diverse fields, collaborating with the Meteorological Research Institute.
How will the observational data be utilized?
The acquired data will be used to improve the accuracy of typhoon intensity forecasts and sea surface temperature data, elucidate ocean-atmosphere mechanisms, and enhance the prediction accuracy of linear rainbands and typhoons.
What kind of platform is envisioned for the future?
The aim is to realize an indispensable marine observation platform for Japan, an island nation, contributing to the improvement of extreme weather prediction accuracy.
How will the results of this research benefit society?
By improving prediction accuracy, it is expected to support early evacuation and disaster preparedness by local governments and residents, contributing to disaster prevention and mitigation.