[13][14] On September 30, a tropical disturbance began to persist near Ebon Atoll of the Marshall Islands, before the Japan Meteorological Agency (JMA) started to monitor the system as a low-pressure area early on the next day.

[2][20] In the afternoon, the JMA upgraded it to a tropical storm and named it Vongfong, when the fragmented banding was wrapping broadly into the slowly consolidating low-level circulation center with a weak eye-like feature.

[1][21] Under low vertical wind shear and excellent outflow, the JTWC indicated that Vongfong had intensified into a typhoon at 06:00 UTC on October 4, as well as the JMA upgraded the system to a severe tropical storm at noon.

[3][22] With an improved northeastward channel into a tropical upper tropospheric trough (TUTT) cell, the storm briefly formed a pinhole eye on October 5, and the JMA upgraded it to a typhoon approximately 330 km (210 mi) east of Guam at 09:00 UTC.

[24] In the second half of day, microwave imageries revealed that a thick eyewall structure had formed under a large central dense overcast, and a new but larger eye began to develop.

Moreover, moderate vertical wind shear was being offset by excellent equatorward outflow and the motion of the system, when Vongfong was passing through the Northern Mariana Islands.

[6] The system started to undergo rapid deepening early on that day, owing to low vertical wind shear and multiple outflow mechanisms including a TUTT cell positioned to the east.

The JTWC upgraded it to a super typhoon at noon, as the system had formed a 40 km (25 mi) round eye surrounded by a symmetric annulus of intense convection.

[30] The typhoon then turned north-northwestward in the afternoon due to some migratory ridging building in the north, when excellent outflow was being enhanced along the poleward side because of the mid-latitude westerlies.

[31] Vongfong totally lost the eye feature owing to increasing southwesterly vertical wind shear on October 11, yet its circulation grew even larger.

[32] After crossing Okinawa Island and entering the East China Sea at 15:30 UTC, the overall structure of Typhoon Vongfong diminished more, resulting in the beginning of a significant weakening trend.

Moreover, cold air stratocumulus clouds were observed streaming into the western periphery of the system, as the low level circulation center had become partially exposed and elongated caused by strong vertical wind shear.

[11] The system accelerated east-northeastward along the northwestern periphery of the subtropical ridge in the afternoon and made landfall over Makurazaki, Kagoshima at 23:30 UTC, right before the JMA downgraded Vongfong to a severe tropical storm only a half of hour later.

[35][36] Isolated deep convection was displaced over the east quadrant of the exposed low-level circulation due to strong westerly vertical wind shear.