Lan then quickly weakened the following day due to the effects of inner ring of cloud tops and well-defined eyewall.

The origins of Typhoon Lan can be traced back to August 5, when the Japan Meteorological Agency (JMA) reported that a low-pressure area had formed east-northeast of Iwo Jima.

[1][2] Environmental conditions were assessed as being marginally conducive for tropical cyclogenesis, with warm sea surface temperatures (SST) near 29–30 °C (84–86 °F) and low vertical wind shear, and good equatorward outflow.

[6] The same day, the agency upgraded to a tropical storm,[7] with the JMA assigning the name Lan for the system.

[9] A banding eye began to appear on satellite imagery; the deep convection had started to consolidate and wrap around the low-level circulation center.

[11] Organization began to steadily increase within the developing eyewall, but the JTWC reported that it did not intensify over the past twelve hours.

[13][14] Lan consolidated and developed a small, defined circulation with satellite imagery revealed a 30 nautical miles (56 km; 35 mi) ragged eye.

The storm maintained its overall convective structure, but the waters beneath the cyclone cooled, prompting a quick weakening trend.

Hundreds of thousands of people have been ordered to evacuate in Aichi, Kyoto, Mie, Nara, and Wakayama prefecture.

[34] A level 3 evacuation was ordered for 26,000 senior residents of a town in Wakayama Prefecture on Tuesday morning due to concerns that heavy rains will cause landslides.

The government has dispatched food and water to the affected districts, and the military has been deployed to assist with rescue and relief efforts.

[40] An amount of rain similar to three times the usual August rainfall was recorded in Tottori Prefecture in a single day, totaling 470 mm (19 in) in 24 hours.

Representatives from several of Japanese prefectures announced that they would postpone commemorating the surrender of Japan in World War II.

[44] An 80-year-old female who was stuck in Saji Town was taken to the hospital for emergency care due to cardiac arrest, but she perished, another 64 remain injured.