NAHA - Typhoon No. 13, which formed on the afternoon of July 27, is expected to intensify rapidly into a violent storm as it draws in clusters of highly developed clouds, though forecasts remain sharply divided over whether it will eventually approach Japan.
Satellite images show that the storm's cloud circulation has become increasingly distinct since its formation. Large masses of powerful convective clouds are also present around the system, and the typhoon is expected to grow substantially as it absorbs them.
As of July 27, the storm had a central atmospheric pressure of 998 hectopascals and maximum sustained winds of 20 meters per second near its center. Although only six hours had passed since its formation, wind speeds were already increasing.
The typhoon was moving west at 30 kilometers per hour.
Sea surface temperatures along its expected path are extremely high, with a broad area exceeding 30 degrees Celsius to the northwest. The warm waters are expected to supply the storm with large amounts of water vapor, while upper-level wind conditions are also favorable for development.
These conditions raise the possibility that the typhoon will strengthen rapidly.
The storm is forecast to become strong enough to generate violent winds by the night of July 29. Its maximum sustained winds near the center are expected to reach 50 meters per second on July 31, making it a very strong typhoon.
By the night of August 1, Typhoon No. 13 is forecast to have a central pressure of 915 hectopascals and maximum sustained winds of 55 meters per second, placing it in the violent category, the highest level on Japan's typhoon intensity scale.
Forecast uncertainty remains relatively limited through August 1, resulting in a comparatively narrow forecast cone. However, the storm's path beyond that point remains highly uncertain.
Atmospheric conditions at an altitude of about 5,500 meters on the morning of August 2 are expected to play a major role in determining its course.
The Pacific high-pressure system is forecast to extend broadly east of the typhoon, while a trough of low pressure is expected farther east. If the storm is caught by the trough, it could turn north and travel along a path east of Japan.
If the summer high-pressure system weakens, however, the typhoon could remain farther south and continue moving west across waters south of Japan.
Forecast models generally indicate that the storm is likely to travel northwest for some time. After moving a certain distance westward, however, projected tracks diverge significantly, splitting broadly between a northward route east of Japan and a westward route across southern waters.
An ensemble forecast produced by a European meteorological agency, which runs multiple simulations using slightly different initial conditions, shows particularly wide variation.
The average projected position on August 6 is offshore of the Kii Peninsula, but individual forecasts differ substantially. Some simulations keep the typhoon far from Japan, while others take it toward Kyushu or bring it closer to eastern Japan, including the Kanto region.
The storm has only recently formed, and any potential approach to Japan would still be more than a week away, making long-range forecasts highly uncertain.
Even if Typhoon No. 13 does not directly approach or make landfall in Japan, its expected development into a violent storm could produce significant effects over a wide area.
The likely impact is expected to become clearer after the beginning of August, and residents are being urged to closely monitor the latest typhoon forecasts.
Source: ウェザーニュース
