Typhoon Kompasu (08W) and Tropical Storms Namtheun and Lionrock29.0N 129.6E
Upon opening the full image, Typhoon Kompasu (08W) can be seen between Japan (north) and the Philippines (south). In the animated image, Kompasu is the system to the right, whose track is marked; also visible to the left in the full version are Tropical Storm Namtheun (09W) and Tropical Storm Lionrock (07W).
Typhoon Kompasu began as an area of low pressure that formed on August 27th, about 305 km (200 mi) to the east of the island of Yap. At that time, the system was disorganized due to high vertical wind shear.
The next day, the system started to move northwest and crossed the island of Guam. That evening, the system was located about 370 km (250 mi) northwest of Guam, in an area of low vertical windshear and a favorable environment. A Tropical Upper Tropospheric Trough (TUTT) was located to the east of the system. At that time, the Japanese Meteorological Agency upgraded the system into a tropical depression.
Around midday on August 29th, the Joint Typhoon Warning Centre (JTWC) issued a Tropical Cyclone Formation Alert (TCFA) on the system as the Low Level Circulation Center (LLCC) became more organized. On the morning of that same day, the JTWC announced that the system had quickly developed into a tropical storm and assigned the designation “08W”.
Intensification continued, and by midday on August 30th, the JMA reported that the depression had intensified into a tropical storm and assigned its international designation “Kompasu”. In addition, PAGASA also announced that the low pressure to the northeast of Batanes had formed, and assigned its local name: “Glenda”. Six hours later, the JMA reported that Kompasu had intensified rapidly into a severe tropical storm. At the same time, the JTWC also upgraded Kompasu to a category 1 typhoon.