When to go · Seongnam
Seongnam in September
Great month. Inside Seongnam's best window: Mar–May, Sep–Nov.
Key facts
- Verdict
- Great
- Temperature
- 26°C (79°F)79°F (26°C) / 17°C (63°F)63°F (17°C)
- average high / low
- Rain days
- 9
- Crowds
- Medium
- South Korea overall
- Prices
- Medium
- South Korea overall
Verdict
Inside Seongnam's best window: Mar–May, Sep–Nov.
Is another month better than September?
No other month rates higher than September for Seongnam in this guide.
Weather in September
- SeongnamHighs around 26 °C (79 °F), lows around 17 °C (63 °F), rain on about 9 daysHighs around 79 °F (26 °C), lows around 63 °F (17 °C), rain on about 9 days
Festivals and holidays
Dates as our data lists them. Moving holidays (lunar and Islamic calendars, Easter) shift every year: check the date for your year before you build a trip on it.
Chuseok (harvest festival) big impact
Chuseok: 24–26 Sep 2026 (passed); about 14–16 Sep 2027 (check) · South Korea
Same three-day shutdown as Seollal; the largest travel peak of the year.
Crowds and prices
- Crowds · South Korea overall
- Medium
- Prices · South Korea overall
- Medium
South Korea overall: Heat eases; typhoon risk remains and Chuseok shuts the country for 3 days in many years.
Compare two months
Weather, crowds and prices for any two months in Seongnam, side by side.
Verdict
Sep: Great
Mar: Great
Daytime high
Sep: 26 °C (79 °F)79 °F (26 °C)
Mar: 11 °C (52 °F)52 °F (11 °C)
Night low
Sep: 17 °C (63 °F)63 °F (17 °C)
Mar: 2 °C (36 °F)36 °F (2 °C)
Rain days
Sep: 9
Mar: 6 (better)
Crowds
Sep: Medium
Mar: Medium
Prices
Sep: Medium
Mar: Medium
Festivals listed
Sep: 1
Mar: 0
September: Inside Seongnam's best window: Mar–May, Sep–Nov.
March: Inside Seongnam's best window: Mar–May, Sep–Nov.
Seongnam: figures are long-term averages from this guide, not a forecast.
What to pack
Nothing unusual for the weather this month.