Japan’s 2026 Typhoon Outlook: Increased Risk of Typhoons Approaching Japan in August, with Potential Impacts from Stronger Typhoons in Autumn

2026.06.15

Key Points on Japan’s 2026 Typhoon Trends

• In 2026, the number of typhoons forming from June to July is expected to be around or above normal, and the number of typhoons approaching Japan*1 is also expected to be around or above normal, particularly in August.
• From September onward, the number of typhoons approaching Japan is expected to remain around normal. However, due to the high likelihood of a transition to El Niño conditions, there is a possibility that more developed typhoons may approach Japan in autumn.

Typhoons have a major impact on corporate activities, including logistics delays, store closures, decisions on factory and site operations, and cancellations of outdoor work and events. In particular, businesses should be aware not only of periods when the number of approaching typhoons is high, but also of the possibility that a single typhoon could have a major impact if it becomes well developed or moves slowly.
In this article, we review the 2026 typhoon outlook, the preparations businesses should consider before the typhoon season, and key points for making effective use of weather information.

*1 Number of typhoons approaching Japan: The number of typhoons whose centers come within 300 km of any meteorological station, etc. in Japan.

目次

2026 Typhoon Trends: Increased Risk of Typhoons Approaching Japan, Particularly in August

In 2026, the number of typhoons approaching Japan may be higher than normal, particularly in August, requiring close attention.

According to an analysis using the “2-Year Long-Term Weather Forecast Model,” developed by the Japan Weather Association using patented technology, the number of typhoons forming in 2026 is expected to be around or above normal from June to July.
From August to September, the number of typhoons forming is expected to be generally around normal, while in October it is forecast to be around or below normal.

On the other hand, the number of typhoons approaching Japan is expected to be around or above normal, particularly in August.
In 2026, it is considered highly likely that conditions will transition to El Niño by summer. In association with this, there are expected to be periods in August when the Pacific High extends less strongly toward the vicinity of Honshu, which may make it easier for typhoons to move northward toward Japan.

Number of typhoons approaching Japan nationwide, including Okinawa and Amami

The period when many typhoons form does not necessarily coincide with the period when typhoons are more likely to approach Japan.
When a typhoon forms, businesses should check the latest information and take appropriate measures.

Periods Requiring Particular Attention for Typhoons in Japan in 2026

For typhoons in 2026, companies need to pay attention not only to trends by period, but also to responses that take into account changes in typhoon tracks after formation.

From June to July, convective activity is expected to increase in the western North Pacific, the main area where typhoons form. As a result, the number of typhoons forming through July is expected to be around or above normal.

In August, there are expected to be periods when the Pacific High extends less strongly toward the vicinity of Honshu. As a result, typhoons may be more likely to move northward toward Japan, and the number of typhoons approaching Japan is expected to be around or above normal.

From September onward, the number of approaching typhoons is expected to be around normal.
However, if conditions transition to El Niño, the locations where typhoons form may shift southeast of normal, in other words toward waters closer to the International Date Line and farther from Japan.
In such cases, typhoons would travel a longer distance over the ocean before approaching Japan, increasing the risk that they approach Japan at greater intensity. Therefore, even if the number of approaching typhoons is not high, attention should still be given to the potential for a single typhoon to have a significant impact.

Pay Attention Not Only to the Number of Approaching Typhoons, but Also to Their Intensity, Track, and Speed

In the latter half of the typhoon season, even if the number of approaching typhoons is around the normal level, the impacts of intense typhoons could be significant.

When assessing typhoon risk, it is important to look not only at “the number of typhoons,” but also at “how intense the approaching typhoons become,” “which areas they affect,” and “how quickly they move.”

In 2026, the number of typhoons approaching Japan from September onward is expected to be around normal. However, there is a possibility that intense typhoons may approach Japan.
Even when the number of approaching typhoons is not particularly high, a single typhoon can cause significant impacts through heavy rainfall, strong winds, high waves, and storm surges. Therefore, continued vigilance is required throughout the latter half of the typhoon season.

In particular, slow-moving typhoons can prolong the effects of heavy rainfall and strong winds, increasing the risk of flooding, landslides, power outages, traffic disruptions, and logistics delays. For businesses, it is important not only to monitor forecasts of typhoon activity, but also to stay updated on the latest typhoon information and assess the expected duration and geographic extent of impacts from rainfall and strong winds.

In 2026, there is a high likelihood of a transition to El Niño conditions by summer, and there is also a possibility that a positive Indian Ocean Dipole event*2 may develop. Under such meteorological conditions, the impacts of a single typhoon could become severe due to stronger typhoons and slow-moving systems.

During the latter half of the 2026 typhoon season, attention should be paid not only to the number of approaching typhoons, but also to their intensity, track, and speed.

*2 Positive Indian Ocean Dipole event: A climate phenomenon in which sea surface temperatures are higher in the western Indian Ocean and lower in the eastern Indian Ocean. It may affect the extension of the Pacific High near Japan and the tracks of typhoons.

What is a Typhoon?

A tropical cyclone is an intense, rotating storm system that forms over warm tropical or subtropical oceans. Of these, when one develops in the northwestern Pacific (north of the equator and west of 180°E) or the South China Sea, with a maximum sustained wind speed (10-minute average) of approximately 17 m/s (34 knots, Beaufort scale 8) or higher within the low-pressure area, it is called a “typhoon.”

Japan’s autumn typhoon season peaks in September and October.
The average number of typhoons forming is 3.7 in July, 5.7 in August, 5.0 in September, and 3.4 in October, showing a tendency for increased activity from July to October.
Starting around July, typhoons tend to follow courses that bring them close to Japan, with September being the month when they are most likely to take tracks that pass through the vicinity of Japan.
Autumn typhoons often accelerate as they approach Japan, and they sometimes intensify the activity of the autumn rain front, bringing heavy rainfall. Every year around this time, such typhoons cause significant damage in Japan.

For more information on typhoons and heavy rain in Japan, please see:
Typhoons and Heavy Rain in Japan: Business Risks for Global Companies and the Use of Weather Data Part 1 / Part 2

Impacts on Business Operations and Preparations Before the Typhoon Season

Impacts on Business Operations

Typhoons can affect business operations even before they approach. Depending on a typhoon’s track and timing, companies may need to make decisions across a wide range of activities, including logistics, manufacturing, retail operations, outdoor work, and event management.

In 2026, the number of typhoons approaching Japan is expected to be around or above normal, particularly in August.
August is also a period when summer holidays, homecoming travel, events, and increased logistics demand overlap. As a result, disruptions to transportation and logistics caused by approaching typhoons may have broader impacts on business operations.

From September onward, even if the number of approaching typhoons remains around normal, attention should be paid to the possibility of intense typhoons approaching Japan. When typhoon impacts are expected to be significant, companies may need to make decisions regarding temporary closures, operational suspensions, delivery delays, and event cancellations.

Preparations Before the Typhoon Season

Effective typhoon preparedness requires not only actions immediately before a typhoon approaches, but also advance planning before the season begins.
This is particularly important for companies with multiple locations and for businesses that rely on logistics, retail operations, or outdoor work. These organizations should establish decision-making criteria in advance, taking regional differences in risk into account.

Typhoon preparedness involves more than simply monitoring weather information. It is also important to determine in advance when decisions will be made, who will make them, and what criteria will be used based on that information. If these criteria are unclear, responses may be delayed or inconsistent across different locations.

Weather Information and Services to Use at Each Stage

The weather information that should be monitored for typhoon preparedness differs depending on the stage: before the season, after a typhoon forms, and before it approaches.

It is important to understand seasonal typhoon trends early, review multiple track scenarios once a typhoon forms, and, as a typhoon approaches, assess site-specific risks such as heavy rainfall, flooding, and transportation disruptions.
By using weather information appropriately at each stage, companies can better manage and reduce the potential impacts of typhoons on their operations.

Use the “2-Year Long-Term Weather Forecast” for Pre-Season Planning

To incorporate expected typhoon season trends into medium- to long-term business planning, the 2-Year Long-Term Weather Forecast can be used.
In addition to providing more detailed outlooks for typhoon formation and approaches to Japan than those presented in this article, the service offers monthly long-term forecasts for temperature, precipitation, snowfall, sunshine duration, and other variables through reports, data products, and consulting services.

* Service details: 2-Year Long-Term Weather Forecast (only available in Japanese)
For more details, please see:
What are Long-Term Forecasts? JWA’s Proprietary “2-Year Long-Term Weather Forecast” and Its Business Applications Part 1 / Part 2

Use “Probabilistic Scenario-Based Typhoon Forecasts” for Early Response After Typhoon Formation

Typhoon track forecasts inherently involve uncertainty.
When a typhoon has the potential to approach Japan, even slight changes in its projected track can alter the affected areas, timing, and expected intensity of rainfall and winds.
To assess multiple track scenarios after a typhoon forms, Probabilistic Scenario-Based Typhoon Forecasts can be used. By reviewing forecasts and probabilities across multiple scenarios, businesses can take earlier action regarding logistics, facility operations, retail operations, and event-related decisions.

*Service details and forecast examples: Probabilistic Scenario-Based Typhoon Forecasts (only available in Japanese)

Use “Weather Risk Information for Businesses” to Assess Site-Specific Risks

The impacts of typhoons are not uniform across Japan.
Even with the same typhoon, affected areas vary depending on the storm’s track and the distribution of rain bands.
To identify heavy rainfall and flood risks at individual facilities—such as factories, retail outlets, offices, and logistics centers—Weather Risk Information for Businesses can be used. The service provides site-specific risk information up to 14 days in advance, supporting decisions on closures, commuting restrictions, equipment protection, and flood preparedness measures.

*Service details and use cases: Weather Risk Information for Businesses (only available in Japanese)

Use the “GoStop Management System” for Logistics Decisions

When a typhoon approaches, logistics operations may be significantly affected by road closures, disruptions to rail, port, and airport operations, delivery delays, and the need to ensure driver safety.
To support early decisions on transportation feasibility, route adjustments, and coordination with shippers and customers, the GoStop Management System for logistics can be used. It provides transportation impact risk information up to six days in advance of severe weather, supporting planning and coordination among stakeholders.

*Service details and use cases: Logistics-oriented GoStop Management System

Weather Data API

JWA’s weather API is designed to allow developers to access highly accurate weather information for any location. Data such as temperature, humidity, precipitation, snowfall, wind direction and speed, and general weather conditions can be retrieved in a single request through a user-friendly API.
For the overview, please see: Weather API Overview

FAQ

Conclusion

In 2026, typhoon activity is expected to be around or above normal from June to July, with the number of typhoons approaching Japan also expected to be around or above normal, particularly in August. From September onward, the number of approaching typhoons is expected to remain around normal. However, due to the high likelihood of a transition to El Niño conditions, there is a possibility that intense typhoons may approach Japan.

For businesses, typhoons can affect a wide range of operations, including logistics, manufacturing, retail operations, outdoor work, and event management. During the 2026 typhoon season, it will be important to prepare early and monitor not only the number of approaching typhoons, but also their intensity, track, geographic extent, and duration of impacts.

Businesses can strengthen their preparedness by using:

• the 2-Year Long-Term Weather Forecast to understand seasonal trends
• Probabilistic Scenario-Based Typhoon Forecasts to assess multiple track scenarios after typhoon formation
• Weather Risk Information for Businesses to evaluate site-specific heavy rainfall and flood risks
• the GoStop Management System for logistics to assess potential transportation disruptions

Professional Profile

Kumi Okoshi

The weather analysis and discussion of business impacts presented in this article have been supervised by Kumi Okoshi, Senior Data Analyst at Japan Weather Association.

In her role within JWA’s product demand forecasting business, she conducts market-oriented analyses and demand forecasts for industries such as food, daily necessities, and apparel, and provides consulting services to help companies address a wide range of business challenges.

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