Typhoon Phyllis was one of seven tropical cyclones in 1975 to pass within range of the Japan Meteorological Agency's (JMA) radar surveillance.

The typhoon accelerated north while rapidly intensifying, and on the evening of August 14, Phyllis reached its peak intensity of 225 km/h (140 mph).

Typhoon Phyllis turned northwest, making landfall over Shikoku on August 17, with winds of 145 km/h (90 mph).

During the first couple weeks of August 1975, the Western Pacific monsoonal trough extended from central China to Guam.

Numerous surface circulations appeared in this trough as early as the August 8, and three days later, a tropical disturbance was spotted by the Joint Typhoon Warning Center (JTWC) some 705 km (440 mi) west-southwest of Guam.

[1] Due to the cyclone's proximity to the country, the Philippine Atmospheric, Geophysical and Astronomical Services Administration also monitored the storm and assigned it with the local name Etang.

Initially, the storm's low- and upper-level circulation were displaced by 200 km (125 mi), but on the morning of August 13, the centers had become vertically stacked.

Based on aircraft reports of 115 km/h (70 mph) winds to the west-southwest of the center,[1] Phyllis was believed to have obtained typhoon intensity midday on August 13.

Based on this, the JTWC estimated that the typhoon reached its maximum intensity of 225 km/h (140 mph), equal to Category 4 status on the SSHWS.

After turning to the northwest, Phyllis once again accelerated, and on August 16, passed roughly 320 km (200 mi) southeast of Shikoku.

[20] Kōchi Prefecture sustained the worst effects from the storm,[21] where 21 people were killed,[22] including one woman who was electrocuted.

[22] In addition to the effects on Japan, the outer rainbands of the typhoon dropped heavy rains in Taiwan, causing widespread damage.

[24] While the typhoon's inner core bypassed South Korea,[24] Phyllis dropped heavy rainfall across the country, peaking at 142 mm (5.6 in) in Daegwallyeong-myeon.