From late May to early June 2026, a large, slow-moving storm system tracked north-northwest across the Philippine Sea toward southern Japan. As Typhoon Jangmi progressed, its vast rain belt dumped heavy rain over a wide area, raising concerns of flooding in several locations.
Nighttime images captured by the VIIRS (Visible Infrared Imaging Radiometer Suite) instrument onboard the Suomi Nuclear Power Plant satellite show the storm around 16:40 UTC on May 30 (1:40 a.m. May 31, Japan Standard Time). At the time, the Joint Typhoon Warning Center (JTWC) reported sustained winds of 120 km/h (75 mph) based on a one-minute average. This wind speed is comparable to a Category 1 hurricane on the Saffir-Simpson Hurricane Anemometer.
Giant eye visible in nighttime satellite images
Satellite views show Jangmi’s eyes and surrounding eyewalls very clearly. The eye was relatively large compared to many tropical cyclones, said Scott Brown, a research meteorologist at NASA’s Goddard Space Flight Center.
This image also appears to show low-level circulation along the eastern side of the eye. These rotating features, known as mesocyclones, are partially hidden beneath clouds in the sky. Brown noted that while these structures are visually impressive, they are considered a normal feature in this type of storm.
The storm strengthens towards Japan
A second satellite image collected a day later by the NOAA-20 satellite’s VIIRS instrument shows a broader view of the storm. This image was acquired around 16:40 UTC on May 31 (1:40 a.m. June 1, Japan Standard Time).
By then, Janmi had strengthened slightly, with sustained winds increasing to 130 km/h (80 mph).
In both satellite images, the center of the storm remained south of Okinawa. However, Jangmi’s extensive outer cloud belt had already spread over parts of Japan as the system continued northward.
Flooding concerns along Japan’s Pacific coast
According to the forecast, the typhoon is expected to pass near Okinawa from June 1st to 2nd, then change course northeast toward the Amami region. According to reports, meteorologists expected the storm to continue to dump heavy rain, especially along Japan’s Pacific coast.
NASA Earth Observatory image by Michala Garrison using VIIRS day/night band data from NASA EOSDIS LANCE, GIBS/Worldview, and the Joint Polar Satellite System (JPSS).
