Sejong in Fall

In fall (September, October and November), Sejong sees average daytime highs around 20°C and overnight lows near 10°C, with 243 mm of precipitation over about 19 wet days across the season. It is the 2nd-warmest season and the 2nd-wettest season.

Over the season highs ease from about 28°C in early September to 9°C by late November. The sky is clear or mostly clear about 42% of the time across fall, and the air most often feels dry.

Fall is Sejong's best season of the year to visit on our travel score. For the whole year in context, see Sejong's year-round climate.

Avg daytime high
20°C
2nd-warmest season
Avg overnight low
10°C
Precipitation
243 mm
19 wet days
Avg wind
8 km/h
Travel score
6.1
best season of the year
Months
Sep · Oct · Nov

Temperature in Sejong in Fall

Average highAverage lowShaded bands: 10–90% of days

Over the season highs ease from about 28°C in early September to 9°C by late November.

A typical fall day in Sejong reaches about 20°C and drops to 10°C overnight. The warmest of the three months is September, the coolest November.

10°20°30°SepOctNov

How fall really feels in Sejong

Once humidity and wind are folded in, fall brings about 0 days that feel above 32°C and 13 that feel at or below 0°C.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
13
wind chill below the day's low

The story in fall is cold — wind chill drags the overnight "feels like" below the raw low.

Sejong weather by month

How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.

MonthHigh / Low (°C)Rainfall (mm)Wet daysSnow daysDaylight (hours)Travel score
Jan / -5°224.32.29.80.0
Feb / -3°304.31.510.60.7
Mar12° / 496.71.111.73.6
Apr19° / 797.4012.96.5
May24° / 13°867.5013.97.2
Jun28° / 18°1228.5014.56.1
Jul29° / 22°25616.1014.24.5
Aug30° / 22°22615013.44.4
Sep26° / 17°1438.5012.26.8
Oct20° / 10°584.8011.17.4
Nov13° / 435.90.2104.0
Dec / -3°234.51.49.50.5

Cloud cover in Fall

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 42% of the time across fall.

0%25%50%75%100%SepOctNov

Chance of precipitation in Fall

Any precipitationSnow

Sejong gets around 243 mm of rain and snow over 19 wet days across fall. The line is the day-by-day chance of measurable precipitation.

0%10%20%30%40%50%SepOctNov

Humidity in Fall

DryComfortableHumidMuggyOppressiveMiserable

Most of fall feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.

0%25%50%75%100%SepOctNov

Wind in Fall

Winds average 8 km/h across fall.

051015SepOctNov

Sunrise & sunset in Fall

DaylightNight

Daylight runs from about 12 h 48 min in early September to 9 h 42 min by late November. The lit band spans sunrise to sunset each day.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMSepOctNov

Solar energy in Fall

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day across fall, about 3.5 kWh/m².

012345SepOctNov
Planning a trip in fall

Hazard calendar for Sejong

In seasonPeak

In fall, Sejong overlaps its rainy season season. The full year is below, with each hazard's peak months called out.

Sejong's rainy season runs June–September, when most of the year's rain falls.

Rainy season
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is fall a good time to visit Sejong?

Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.

6.1
Sightseeing
1st-best month of the year
3.6
Beach & pool
2nd-best month of the year

fall is a reasonable time to visit Sejong for sightseeing.

What to pack for Sejong in Fall

From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In fall, Sejong sees daytime highs around 20°C and nights near 10°C. Worth packing: light clothes, a warm layer and rain gear. About 19 days see rain.

light clothesa warm layerrain gear

UV index in Sejong in Fall

LowModerateHighVery highExtreme

Clear-sky midday UV across fall averages around 5 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Sejong peaks around August 14 at about 8 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near December 23 at about 2 (moderate).

The index reaches 3 or more — the level where the WHO recommends sun protection — in 10 months of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highHighModerateAug 14UV 8Dec 23UV 2
UV index (midday)Level
Jan2Moderate
Feb3Moderate
Mar5Moderate
Apr6High
May7High
Jun7Very high
Jul8Very high
Aug8Very high
Sep8Very high
Oct5High
Nov3Moderate
Dec2Low

Air quality in Sejong in Fall

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.

Air quality in Sejong is worst in March — around 80 µg/m³ PM2.5 (unhealthy), about 1.8× the cleanest month (July, 45 µg/m³).

Modeled monthly averages (CAMS reanalysis, 2015–2024).

0306090JanFebMarAprMayJunJulAugSepOctNovDecUnhealthyPoorUnhealthyMar 1479 µg/m³Jul 2345 µg/m³
PM2.5 (µg/m³)Level
Jan69Unhealthy
Feb72Unhealthy
Mar80Unhealthy
Apr65Unhealthy
May58Unhealthy
Jun54Poor
Jul45Poor
Aug45Poor
Sep56Unhealthy
Oct67Unhealthy
Nov72Unhealthy
Dec65Unhealthy
Location & terrain

Where is Sejong?

Sejong sits at 36.6°N, 127.3°E, 49 m above sea level, in South Korea. The nearest listed city is Cheongju-si, 18 km away.

Seonghwan

Topography around Sejong

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Sejong.

Within 3 km, the terrain around Sejong has only modest variations in elevation — a maximum elevation change of 148 m around an average of 39 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 445 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,213 m.

The land around Sejong is covered by cropland (43%), artificial surfaces (28%) and trees (21%) within 3 km, trees (54%) and cropland (22%) within 16 km, and trees (62%) and cropland (23%) within 80 km.

3 km
148 m
16 km
445 m
80 km
1,213 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Fall weather nearby: Cheongju-si 18 km · Gongju 21 km · Cheonan 27 km · Daejeon 28 km · Chinch'ŏn 32 km · Asan 33 km · Jungpyong 34 km · Seonghwan 39 km

South Korea travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type C / F
220 V · 60 Hz
Prices
≈ 57% of US
price level, 2025
GDP per capita
$36,227
2025
Happiness
6.0 / 10
World Happiness, 2025
Safe drinking water
99%
of population, 2024
Homicide rate
0.5
per 100k, 2023
Road deaths
8.6
per 100k/yr, 2019
Income group
High
World Bank
English
Moderate
EF EPI 522
Religion
none 60%Protestant 17%Buddhist 16%Catholic 6%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Sejong (36.5924°, 127.2922°, elevation 49 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.