Ulsan Weather in September
During September, Ulsan experiences high daytime temperatures of 27°C (81°F) and cooler nights around 20°C (68°F). September sits within the rainy season, and part of the summer season, so expect regular and often heavy rainfall.
Rainfall in Ulsan in September
As part of the rainy season, Ulsan sees around 11 days of rain in September, with an average of 180 mm (7.1 in). Showers during the rainy season tend to be heavy and can come down intensely. An umbrella is often not enough, so a poncho or waterproof jacket is a better choice.
Temperature in Ulsan in September
Temperatures in Ulsan in September top out at 27°C (81°F) and drop to 20°C (68°F) overnight. Experience the summer season in September. This kind of day-to-night contrast is typical for this time of year. With lows of 20°C (68°F), nights are cool. If you're out after dark, an extra layer will keep you comfortable. The cooler air at night is also great for getting a good rest.
Sunshine in Ulsan in September
With about 152 hours of sunshine, the area enjoys a nice balance of sun and rainy moments, creating a pleasant environment.If your ideal day consists of dry skies and pleasant temperatures, October typically offers the best circumstances for Ulsan.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit South Korea, check out our Ulsan's climate page.
Ulsan Temperature in September
Min Temperature
20°C (68°F)
Max Temperature
27°C (81°F)
Chance of Rain
36%
Precipitation
180 mm (7.1 in)
Rainy days
11 days
Humidity
75%
Sunshine
152 hours
Percentage Sunshine
41%
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Ulsan typically drop from around 28°C (82°F) at the start of September to approximately 25°C (77°F) by the end. Nights are pleasant, with lows typically ranging from 15°C (59°F) to 21°C (70°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Ulsan in September
Browse day-by-day weather records for Ulsan spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Ulsan historical weather extremes in September
According to our 49 years of weather records for Ulsan, the following extremes were recorded between 1976 and 2025.
- The hottest September day on record in Ulsan reached 35°C (95°F) (September 2, 1994).
- Ulsan experienced its chilliest September day on September 20, 1986, reaching only 18°C (64°F).
- The coldest night in September in Ulsan was on September 18, 1995, with a minimum of 7°C (45°F).
Best Places in South Korea in September
Find out more about the weather in South Korea and which places have the best travel conditions in this month. See all of South Korea in September →
perfect weather
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tolerable
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What to Wear in Ulsan in September
Warm temperatures in September make for comfortable sightseeing weather. Pack breathable fabrics like cotton shirts, knee-length shorts or skirts, and comfortable walking shoes. A thin long sleeve for indoor spaces is handy. Heavy rain is guaranteed, please bring a good poncho and waterproof everything! Bring sunglasses since you'll have some sunny periods throughout the monthWhat To Do in Ulsan in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit South Korea, check out our Ulsan's climate page.
Temperature Rainfall Sunshine Humidity
See the full Ulsan climate overview or explore weather in South Korea.
