It finally attained typhoon status on July 9, soon after developing an eye, and began to intensify at a brisker clip.

Considered by the media to be the worst typhoon to hit South Korea in 28 years, Thelma brought widespread damage throughout the nation.

[nb 1] Due to the impact of the typhoon to South Korea, over 167,000 government workers, including thousands of military reserves, were mobilized to search for survivors and repair damage.

Although it was initially not well organized, the Joint Typhoon Warning Center (JTWC) started monitoring the system at 06:00 UTC on July 6 due to its well defined circulation.

[1] By that afternoon, organization Situated within a favorable environment of upper-level divergence, the Japan Meteorological Agency (JMA) started tracking the system early on July 7.

A Hurricane Hunter aircraft at 00:00 UTC on July 8 suggested that the depression had degenerated an open wave, with no closed surface circulation.

After turning west while accelerating, the system began to organize, and the JTWC upgraded the depression into a tropical storm midday on July 8.

[4][nb 3] Around this time, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) also started to track the storm and assigned it with the local name Katring.

[2] Over the next 36 hours, Thelma entered a period of rapid deepening,[1] and by 1800 UTC July 10, the JMA increased the intensity to 160 km/h (100 mph).

[2] During the following afternoon, the JTWC upgraded Thelma to a super typhoon, the first of the season, based on Dvorak-based satellite intensity estimates.

[1] Shortly after attaining maximum intensity, cold tops surrounding the eye began to warm and poleward outflow became restricted to its north.

Early on July 16, Thelma entered the Sea of Japan and according to the JTWC, dissipated near Vladivostok,[7] although its remnants were followed by the JMA for two more days.

[7] Four people, including two women, drowned after their fishing boat capsized in the swollen San Jose River in Namolan.

[13] Although Thelma had weakened considerably prior to landfall, the typhoon was considered by press reports to be the worst to strike South Korea since 1959.

[25] As a result of the impact, over 167,000 government workers,[28] including thousands of military reserves, were mobilized to search for survivors, as well as repair roads, waterways, buildings,[19] and power lines.

Approximately 100 angry farmers blocked a road with vehicles near the southern town of Sanchong to complain that they were not getting emergency aid faster enough and also demanded full compensation for destroyed homes and crops.

Fishermen and farmers who suffered property losses were allowed to borrow up to a $3,720-interest free loan from banks and were also awarded a tax break.