Khanun started as a low-pressure area, where it then rapidly intensified into a Category 4-equivalent typhoon on the Saffir–Simpson scale over the Philippine Sea on August 1, before undergoing an eyewall replacement cycle.

Khanun weakened slightly as it moved closer to the Ryukyu Islands, battering them with heavy rain and strong winds.

Steady weakening continued as Khanun approached the Korean Peninsula and it eventually made landfall on Geojedo in South Korea.

After Typhoon Doksuri devastated several countries,[1] the Japan Meteorological Agency (JMA) announced the formation of a low-pressure area in the Pacific Ocean.

[2][3] Analysis from the JMA indicated that the system was in a favorable environment for development, with warm sea surface temperatures and low vertical wind shear.

[4] The Joint Typhoon Warning Center (JTWC) issued a Tropical Cyclone Formation Alert for an area of convection, east of Yap.

[11] Tracking northward due to a nearby mid-level subtropical high-pressure area, Khanun intensified into a severe tropical storm.

[19] Khanun weakened further due to an ongoing eyewall replacement cycle, allowing its eye to grow massively, but degrading its overall structure.

[20] The inner eye began to encounter colder ocean temperatures on infrared satellite imagery, surrounded by a symmetric ring of cold.

[21] Despite the cycle on August 3, Khanun had moved over cooler sea surface temperatures, and hence continued its weakening trend.

[24] Following structural weakening, the JMA and JTWC downgraded Khanun to a severe tropical storm, with estimated winds of 95 km/h (60 mph).

[30][31] Around 00:00 UTC on August 10, Khanun made landfall on Geojedo Islands in South Korea with winds of 85 km/h (50 mph).

[43] Off the coast of Ishigaki Island, the cargo ship Xin Hai Zhou 2 (which had run aground in January) broke in half amid rough seas produced by the typhoon.

[46] On mainland Japan, poor weather forced the cancellation of 25 San'yō Shinkansen services between Hiroshima and Kokura stations on August 9 and 10, affecting 5,200 passengers.

[55] South Korean President Yoon Suk Yeol ordered the government to provide immediate and sufficient support to those affected by Typhoon Khanun.

[62] North Korea warned its citizens to prepare for the typhoon, declaring that all governing party organizations "should wage a dynamic struggle to minimize the damage.

[65] The Korean Central News Agency (KCNA) reported that Khanun also caused minor damage, which resulted in broken tree branches.

[70] North Korean leader Kim Jong Un reportedly visited the typhoon-affected districts in Ogye-ri, Anbyon County in Kangwon Province, oversaw the recovery efforts.

[77] As rains continued throughout the day, the Angat Dam reached its spilling level of 195.88 cubic metres (6,917 cu ft).

[78] Khanun is posing a threat to Taiwan, and President Tsai Ing-wen urged the public to avoid outdoor activities including hiking, fishing, and other coastal pursuits.

[84] Approximately 500 people were stranded on the mountainous villages across central and southern Taiwan due to the rainfall caused by Khanun.

[90] The torrential rain caused damage to roads, bridges, and power supply, along with disrupting at least 20 passenger train services.