East Asia in September: Weather, Crowds & What to Expect
Climate Map for September
Average temperature across East Asia in September.
Country Weather in September
| Country | High | Low | Rain | UV | Feels |
|---|---|---|---|---|---|
| China | 27° | 21° | 129 mm | high | Warm |
| Japan | 26° | 20° | 207 mm | high | Mild |
| South Korea | 25° | 16° | 150 mm | high | Mild |
| North Korea | 25° | 14° | 135 mm | high | Mild |
| Taiwan | 30° | 23° | 330 mm | very high | Warm |
| Mongolia | 16° | 1° | 33 mm | high | Cold |
Representative figures from each country's largest city. High / low are average daily temperatures (°C); “Feels” allows for humidity.
Mongolia & Inner Mongolia (northern China)
September brings crisp mornings and bright, clear days that are ideal for photography in the high-altitude valleys and around Ulaanbaatar; daytime temperatures commonly sit in the teens to low 20s. This is an excellent month for long rides and trekking before the first frosts arrive, with reduced insect activity and good road conditions across popular routes. Accommodation availability improves after the peak, but airlines sometimes begin to reduce schedules in rural areas.
Northeast China & Manchuria (Heilongjiang, Jilin, Liaoning including Harbin and Dalian)
September’s air sharpens quickly into cool, clear conditions ideal for walking historic sites in Harbin and Shenyang; daytime temperatures often settle in the mid-teens to low twenties. Autumn foliage appears in the higher terrain of Jilin and northern Liaoning, offering excellent photography without summer humidity. Services are running full but crowds thin after the summer holidays, making it a smart shoulder-season visit.
North & Central China Plain (Beijing, Tianjin, Hebei, Shaanxi corridor including Xi’an)
Early autumn in September is one of the best times to visit: warm, sunny days with lower humidity and excellent air clarity across the plain and into Shaanxi. The harvest season and Mid-Autumn Festival generate lively local markets and seasonal foods-book ahead if you plan to travel during holidays. This is prime time for historical sightseeing, cycling and day hikes with comfortable daytime temperatures.
Tibetan Plateau & Southwest Highlands (Tibet, Sichuan highlands, Yunnan)
October rapidly cools the plateau and high passes may begin to see early snow, but many southwest valleys still offer comfortable daytime conditions and superb autumn colour. This is a great month for photographers and for quieter trekking if you accept the possibility of sudden weather change. Carry warm clothing for nights and be prepared for earlier closures of some high-mountain tea houses.