Japan’s 2026 Typhoon Outlook: More Typhoons May Develop Through Mid-August | Three to Six Typhoons Forecast to Approach Japan in August [Updated July 30]

2026.06.15

Key Points on Japan’s 2026 Typhoon Trends

• According to preliminary figures as of July 28, 13 typhoons have formed in 2026, a pace above normal.
• Typhoon formation may increase from late July through around mid-August. In August, 4 to 7 typhoons are forecast to form, of which 3 to 6 are expected to approach Japan.
• In addition to dangerously high temperatures before typhoons approach, attention is needed because slow-moving typhoons could bring prolonged periods of heavy rain, strong winds, and rough seas, while areas far from a typhoon may also experience heavy rainfall due to active fronts.

As of July 28, 13 typhoons had formed in 2026 according to preliminary figures, a pace above normal.
According to the latest forecast by Japan Weather Association (JWA), typhoon formation over the waters south of Japan may increase through mid-August. In August, 4 to 7 typhoons are forecast to form, of which 3 to 6 are expected to approach the Japanese archipelago*1.

For typhoons from summer through autumn 2026, attention is needed not only for the number of typhoons forming and approaching Japan, but also for dangerously high temperatures before a typhoon approaches, the prolonged impacts from slow-moving typhoons, and heavy rainfall in areas far from a typhoon.

Rather than waiting until a typhoon is approaching to begin preparations, businesses should make phased use of information with different forecast lead times, including seasonal trends, multiple track scenarios, and site-specific heavy rainfall and flood risks.

*1 A typhoon is considered to have approached the Japanese archipelago when its center comes within 300 km of a meteorological observatory or weather station in Japan.

Table of Contents

Current Status of Typhoon Formation and Approaches to Japan in 2026

In 2026, typhoons formed every month from January through May. After that, 2 typhoons formed in June, and 5 formed by July 28, bringing the total number of typhoons in 2026 to 13.

The normal number of typhoons forming from January through July is 7.9. With 13 typhoons having formed by July 28, typhoon formation in 2026 is proceeding at a faster-than-normal pace.

The number of typhoons approaching Japan has also been high. Three typhoons approached Japan in June, well above the normal number of 0.8. In July, 1 typhoon, Typhoon No. 9, approached Japan by July 27.

Forecast for Typhoon Formation and Approaches to Japan from August to October

According to an analysis using the “2-Year Long-Term Weather Forecast Model,” developed by JWA using patented technology, the number of typhoons forming is expected to be near normal from August to September, and near or below normal in October.
Meanwhile, the number of typhoons approaching Japan is expected to be near or above normal in August and near normal in September and October.

August: Four to Seven Typhoons Forecast to Form, with Three to Six Expected to Approach Japan

August is one of the busiest months of the year for both typhoon formation and typhoon approaches to Japan. In August 2026, between 4 and 7 typhoons are forecast to form, with 3 to 6 expected to approach Japan.

Businesses should also be prepared for the possibility that a new typhoon could form or approach while response efforts for an earlier typhoon are still underway. Reviewing roles and responsibilities, communication protocols, and contingency arrangements in advance can help ensure an effective response.

September and October: Even If the Number of Approaches Is Around Normal, Caution Is Needed

The number of typhoons approaching Japan in both September and October is expected to be around normal. However, a near-normal number of typhoon approaches does not necessarily mean that risks to business operations will also be normal.

Depending on a typhoon’s intensity, track, movement speed, and its position relative to fronts, the impacts of rain, wind, and waves from a single typhoon may be severe and may persist for an extended period.

Typhoon Activity May Increase Through Mid-August

Typhoon activity is expected to increase over the waters south of Japan through around mid-August. Multiple typhoons may develop in succession, and some could move northward toward Japan.

In August 2026, there are expected to be periods when the Pacific High extends less strongly toward Honshu. As a result, typhoons that form over the waters south of Japan may be more likely to move northward toward Japan along the western edge of the Pacific High.

Depending on the position and extent of the Pacific High, typhoons could affect a broad area extending from Okinawa and Amami to western and northern Japan.

However, forecasts one month ahead cannot identify the exact timing, location or track of individual typhoons. This outlook should therefore be viewed as an indication of the overall seasonal tendency for typhoon activity to become more active through mid-August. Once a typhoon forms, the latest forecast information should be monitored closely.

*Probabilistic Scenario-Based Typhoon Forecasts (only available in Japanese)

Four Key Points to Watch During the 2026 Typhoon Season (Summer Through Autumn)

Dangerous Heat May Occur Before a Typhoon Approaches

When a typhoon moves northward from south of Japan, warm air around the typhoon can flow toward Japan. As a result, dangerously high temperatures may occur even before rainfall and strong winds associated with the typhoon affect the area.

In particular, temperatures can rise rapidly in areas where winds blowing toward a typhoon cross mountain ranges and descend on the other side due to the foehn effect. Especially along the Sea of Japan coast, temperatures may rise above normal body temperature, leading to dangerously hot conditions.

*Related article:

What Is the Foehn Effect? Localized Extreme Heat Risks and Heat Countermeasures for Businesses (only available in Japanese)

Slow-Moving Typhoons May Cause Prolonged Impacts

In summer, upper-level winds that steer typhoons are relatively weak. As a result, typhoons may move slowly or follow complex tracks.

When a typhoon moves slowly, heavy rainfall, strong winds, and high waves may persist over the same area for an extended period. In addition, weather conditions may not improve immediately after the typhoon passes.

Heavy Rainfall May Occur Even in Areas Far from a Typhoon

Even in areas far from a typhoon, heavy rainfall can occur when a front remains stationary. Warm, moist air associated with the typhoon can flow into the front, enhancing its frontal activity and increasing the risk of heavy rain.

In such cases, rainfall may intensify before the typhoon’s center approaches, and rain associated with the front may continue after the typhoon has passed. Therefore, businesses should continue to monitor weather information closely, even in areas far from the projected typhoon track.

When monitoring typhoon information, it is important to check not only the typhoon’s center position and forecast track, but also the location of fronts, the movement of rain bands, and local weather warnings and advisories.

Watch for Strong Typhoons Approaching Japan in Autumn

According to the Japan Meteorological Agency, El Niño conditions are believed to have persisted since spring 2026.

In years when El Niño conditions occur, typhoons in the western North Pacific tend to form farther southeast than usual. If typhoons develop over waters far from Japan, they may spend more time travelling over warm ocean waters before approaching Japan, allowing them to strengthen significantly before reaching the region.

El Niño conditions are expected to continue into autumn. However, the number of typhoons forming and approaching Japan from September to October is expected to be generally around normal. Even if the number of typhoons forming or approaching Japan does not exceed normal, a single typhoon may have significant impacts through rainfall, wind, and waves. Continued attention is therefore needed through the latter half of the typhoon season.

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

Conclusion

As of July 28, preliminary figures show that 13 typhoons had formed in 2026, a pace above normal.

Typhoon formation may increase through mid-August. In August, 4 to 7 typhoons are forecast to form, of which 3 to 6 are expected to approach Japan.

From summer through autumn 2026, attention is needed not only to the number of typhoons forming and approaching Japan, but also to dangerously high temperatures before typhoons approach, prolonged impacts from slow-moving typhoons, heavy rainfall in areas far from typhoons, and stronger typhoons approaching Japan later in the season.

Businesses should use information with different lead times, including seasonal outlooks, multiple track scenarios, and site- and route-specific risk information, to make early decisions about operations, logistics, employee commuting, and outdoor work.

FAQ | Frequently Asked Questions About Typhoons in 2026