Even one typhoon can make a map complicated.
At the time, Typhoons No. 15 and No. 16 were both present in waters around Japan, and a tropical depression near Ogasawara was also forecast to possibly develop into the next typhoon. This was the backdrop to the increase in searches for “typhoon information.”
3-line summary
1. Around August 12, Typhoons No. 15 and No. 16 existed simultaneously.
2. Forecasts that an additional tropical depression could develop also increased demand for typhoon information.
3. Even when there are multiple typhoons, the impact on your area must be assessed separately based on each storm’s track, intensity, and advisories.
Why Did “Typhoon Information” Become a Topic of Interest?
A Japan Weather Association weathercaster column reported that, as of August 12, Typhoons No. 15 and No. 16 were present, and that a tropical depression near Ogasawara could possibly develop into Typhoon No. 17.
The mere fact that multiple typhoons exist at the same time does not immediately mean that risk is higher in a specific area. However, it creates more items to check for people planning flights, ship travel, island trips, or marine activities.
Do Multiple Typhoons Merge Together?
The presence of multiple typhoons does not mean they will always directly merge with one another or that their damage will compound. The basic approach is to view them as separate weather systems, each with a different location, track, and intensity.
However, when they exist simultaneously at close range, they can affect the surrounding wind flow. Because such interactions are within the realm of specialized forecasting, it is safer to follow official analyses rather than draw conclusions about the paths of two typhoons from a map alone.
The Information That Matters to You Is Different
More important than a typhoon number are the advisories for where you are or where you will be traveling. Even when the center is far away, swells, strong winds, and heavy rainfall may occur; even when the center is nearby, local impacts vary depending on terrain and the distribution of rain clouds.
- Center location and direction of movement
- Maximum wind speed and the radius of gale-force and storm-force winds
- Area-specific heavy rain, high wave, and strong wind advisories
- Flight, passenger-ferry, and rail service notices
Looking at these four items together enables a far more practical assessment than simply knowing “how many typhoons” there are.
Forecast Maps Keep Changing
The farther into the future a typhoon’s track is forecast, the greater the potential error. A forecast circle is not the size of a typhoon; it indicates the range within which the center may be located.
Therefore, when making major decisions such as canceling travel or evacuating, you should check the latest announcements rather than an old screenshot. It is also important to make a habit of checking the announcement time.
Summary
When multiple typhoons exist at the same time, “typhoon information” itself becomes a topic of interest. But actual safety decisions should be based not on the number of typhoons, but on the wind, rain, and waves expected in your area and on official advisories.
When a typhoon is approaching, repeatedly checking the latest weather announcements and transportation-agency notices is the best preparation.
References
- Japan Weather Association tenki.jp, Weathercaster column on multiple typhoons
- Japan Weather Association tenki.jp, Typhoon information and commentary
- Japan Weather Association, Typhoon disaster-prevention knowledge