Typhoons can draw attention even when they do not make landfall on nearby land.
Typhoon No. 16 Peiro developed near Ogasawara and boosted searches for typhoon information in Japan as it moved northeastward across the Pacific. Forecasts at the time indicated that it was unlikely to directly affect mainland Japan.
3-line summary
1. Typhoon No. 16 Peiro developed from a tropical depression near Ogasawara.
2. Around August 12, forecasts showed it moving northeastward over waters near Wake Island.
3. Even if the direct impact on the mainland is limited, demand for information on maritime, aviation, and island areas may increase.
What Happened
According to typhoon information from Weathernews and the Japan Weather Association, a tropical depression near Ogasawara developed into Typhoon No. 16 Peiro on August 9. The typhoon was then observed and forecast to follow a path toward Pacific waters away from mainland Japan.
The information at this point was a forecast for a specific time. Typhoon tracks and intensity can continue to change depending on surrounding pressure systems and sea-surface conditions, so statements such as “no direct impact” should also be understood within the forecast range at that time.
The Criteria for Receiving a Name
According to an explanation by the Japan Weather Association, a tropical depression is classified as a typhoon when its maximum wind speed develops beyond a certain threshold. Afterward, key observation data include the center’s location, atmospheric pressure, maximum wind speed, direction and speed of movement, and storm boundaries.
Typhoon names are assigned sequentially from a predetermined list. A name is not a warning level, but an identifier indicating that a tropical depression has developed into a typhoon.
Information to Check Even When It Is Far From the Mainland
Even when a typhoon’s center is far from mainland Japan, it can affect island areas such as the Ogasawara Islands, air and ship operations, and wave heights offshore. At sea, high waves and swells can reach areas far from the center.
Therefore, when checking travel and operational information, it is advisable not to look only at the center line on the map, but also to check marine wind and wave advisories for the relevant area, operational notices from airlines and shipping companies, and guidance from local administrative agencies.
The Two Time Points Attached to Typhoon Forecasts
The circles in typhoon forecasts do not represent the typhoon’s size; they indicate uncertainty in the forecast track of its center. The farther away the forecast time, the larger the margin of error, and maps contain different information depending on the time of issuance.
Summaries such as “no impact on Japan” can also mean different things depending on which area and time period they refer to among the mainland, island areas, and offshore waters. The level of risk at sea and in island areas may differ even for the same typhoon.
Summary
Typhoon No. 16 Peiro was forecast to have a low likelihood of directly affecting mainland Japan as it moved over the Pacific. Even so, when multiple typhoons are present, demand increases for checking their tracks and maritime conditions.
The most important standard for typhoon information is the latest official announcement. Travel or maritime activity plans should be checked against advisories and operational notices issued immediately before departure.
References
- Weathernews, Report on the Formation of Typhoon No. 16
- Japan Weather Association tenki.jp, Typhoon Information
- Japan Weather Association, Typhoon and Disaster Prevention Information