Weather in Seoul 🇰🇷
Monthly weather averages & travel planning
December
Avg Temp
3°C
Rain Days
5 days
Sun Hours
8 hrs
Humidity
65%
Asia › 🇰🇷 South Korea › Seoul
Updated: March 2026
Is December a Good Time to Visit Seoul?
4/10
Fair
December is a fair time to visit Seoul (4/10). With 8 daily sunshine hours and only 5 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 11th sunniest of the year in Seoul. December suits travellers visiting for indoor culture, food, and architecture rather than outdoor activities. Pack accordingly for 5 potential rain days. November offers a similar profile at lower hotel rates if dates are flexible. The 3°C highs require proper cold-weather clothing; many visitors underestimate how far the wind chill drops the perceived temperature, particularly near water or at elevated viewpoints. Planning tips: most accommodation categories have availability, and last-minute deals are common. The quieter streets and shorter queues can make this a genuinely enjoyable time to visit for the right type of traveller. Budget-conscious visitors will find the best value of the year in this period.
vs November:11°C avg high
December weather in Seoul is defined by a daily temperature swing from -5°C at night to 3°C during the afternoon. Humidity averages 65%, and you can count on around 8 sunshine hours each day. That combination makes December warm and lush, though dressing in breathable fabrics keeps things manageable.
3°C
37°F
Avg High
-5°C
23°F
Avg Low
5 days
23 mm total
Rain Days
8h
per day avg
Sunshine
65%
Moderate
Humidity
Temperature in Seoul in December
The 8°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 65%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. The UV index of 1 is low, meaning sun exposure is minimal concern and sunscreen is largely optional. Wind averages 15 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 37°F average high, 23°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Temperature Trends
High
Low
Rainfall (mm)
0-20 mm21-50 mm51-100 mm100+ mm
What to Wear in Seoul in December
Morning-5°CBefore the day warms up
Afternoon3°CPeak daytime temperature
Evening-2°CAfter sunset cools down
Packing for Seoul in December means dressing for 3°C days and -5°C evenings. Layering is key: a thermal base, mid-layer fleece, and a windproof outer jacket for 3°C highs that feel colder in the wind. Evening temperatures settle at -5°C, a modest 8°C drop that a light cardigan or denim jacket covers. Comfortable walking trainers are the versatile choice for both outdoor sightseeing and indoor venues.
Local tip: Temple and religious site visits require covered shoulders and knees in most of Seoul's heritage areas. A lightweight scarf or sarong weighs almost nothing and solves the problem instantly.
Events in Seoul in December
December has no major festivals or public holidays in Seoul, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
What to Pack for Seoul in December
Based on 3°C average highs and 5 rainy days
- Heavy winter coat (rated below -5°C)
- Thermal underlayers in merino wool or moisture-wicking synthetic
- Insulated, waterproof boots
- Wool hat, thick gloves, and a windproof scarf
- Comfortable walking shoes (a second pair lets the first air out overnight)
- Universal travel adapter
- Small day pack for city exploration
- Reusable water bottle
Best Activities in Seoul in December
- Vigorous walking tour of the UNESCO heritage districtMidday (12-2pm)The 3°C peak temperature provides ideal conditions for brisk sightseeing walks
- Cycling the riverside or park circuitAfternoon (1-4pm)Cool dry air makes long cycling sessions comfortable without overheating
- Explore hilltop viewpoints and fortressesMorning for clear viewsCold-weather atmospheric clarity gives the longest sightlines of the year
- Open-air Christmas or seasonal marketsAfternoon into eveningCool temperatures make festive outdoor markets genuinely atmospheric
- Afternoon in a world-class museum or galleryAfternoon (2-5pm)Pairs well with outdoor morning activities and provides a mid-day rest from sightseeing
- Coffee-house or traditional cafe culture experienceMid-morning or post-lunchA cultural ritual in this region that rewards slow appreciation regardless of weather
- Evening live music, theatre, or opera performanceEvening shows typically at 7-9pmConsistent evening temperatures make getting to and from evening venues comfortable
- Visit the main botanical garden or city park at seasonal peakYear-round; best light in morningDecember brings distinct seasonal changes to public green spaces worth exploring
- Warm up with traditional hot dishes: local stew, fondue, or braised specialities at a neighbourhood restaurantLunch (12-2pm) or dinner (7-9pm)Cold-weather cuisine is a genuine cultural experience and the best local restaurants serve their heartiest dishes in cooler months
Why is Seoul cool in December?
December in Seoul reflects a mid-latitude climate pattern, with temperatures averaging 3°C by day and -5°C overnight. The city sits at 38 degrees north latitude, where the balance between solar radiation and heat loss drives conditions that are neither extreme nor static. Cold conditions reflect the dominance of polar or continental air masses, which bring dry, stable weather with low humidity. Day-to-night temperature variation of 8°C is moderate and manageable with a single mid-layer. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Frequently Asked Questions
Seoul in December
In December, Seoul experiences average highs of 3°C (37°F) and lows of -5°C (23°F). Expect around 5 rainy days and 8 hours of sunshine per day, with humidity averaging 65%. The 8°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an extra jacket is essential for evenings. UV exposure is moderate at index 1.
Seoul typically sees 5 rainy days in December, with total precipitation of around 23mm. This makes December one of the drier months of the year, and a reliable window for outdoor sightseeing and day trips. Rain showers tend to be brief when they do occur. For context, the driest month in Seoul typically sees 4-6 fewer rain days than December.
Pack a heavy winter coat, thermal underlayers, waterproof insulated boots, and accessories including hats, gloves, and a scarf for Seoul in December. Temperatures regularly fall to -5°C and rarely climb above 3°C during the day. Layering is the key strategy: a base layer, mid-layer insulation, and a windproof outer shell provide flexibility as you move between heated indoor spaces and cold outdoor streets.
Yes, December is an excellent time to visit Seoul. With 8 daily sunshine hours and only 5 rainy days, conditions are ideal for sightseeing and outdoor activities. Temperatures averaging 3°C during the day are comfortable for long walks and outdoor dining. This is peak travel season, so booking accommodation in advance and arriving at popular attractions early in the morning helps avoid the busiest periods.
The average high temperature in Seoul in December is 3°C (37°F), and the average low is -5°C (23°F). The mean daily temperature is approximately -1°C (30°F). The day-to-night range of 8°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Seoul is generally April. April offers the most sunshine at 10 hours per day and only 7 rainy days. Average temperatures reach 17°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around April gives you the best chance of dry, bright weather.
December is shoulder or low season in Seoul, meaning fewer tourists and generally lower prices than peak months. With 8 sunshine hours and 5 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In December, Seoul suits a range of activities thanks to cold temperatures of 3°C. With few rainy days, outdoor activities are highly recommended. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 8 hours of sunshine, parks and waterfront walks are particularly enjoyable.
December ranks 11th sunniest of the year in Seoul, with an average 8 daily sunshine hours. The driest months are January, February, and October. August is the hottest month (29°C avg high); January is the coolest (1°C). From here, temperatures fall 2°C into January. Compared to last month (November: 11°C high, 7 rain days), December is cooler and drier. December is one of the least sunny months, but that often means lower prices and fewer fellow tourists.
Year-Round Climate
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 1°C | -7°C | 4 | 8h | View |
| February | 4°C | -5°C | 4 | 9h | View |
| March | 10°C | 0°C | 6 | 9h | View |
| April | 17°C | 6°C | 7 | 10h | View |
| May | 22°C | 12°C | 8 | 10h | View |
| June | 26°C | 17°C | 9 | 10h | View |
| July | 28°C | 22°C | 17 | 8h | View |
| August | 29°C | 22°C | 16 | 9h | View |
| September | 25°C | 16°C | 8 | 9h | View |
| October | 19°C | 9°C | 5 | 9h | View |
| November | 11°C | 2°C | 7 | 7h | View |
| December | 3°C | -5°C | 5 | 8h | View |
January
4 rain days, 8h sun
1°-7°
February
4 rain days, 9h sun
4°-5°
March
6 rain days, 9h sun
10°0°
April
7 rain days, 10h sun
17°6°
May
8 rain days, 10h sun
22°12°
June
9 rain days, 10h sun
26°17°
July
17 rain days, 8h sun
28°22°
August
16 rain days, 9h sun
29°22°
September
8 rain days, 9h sun
25°16°
October
5 rain days, 9h sun
19°9°
November
7 rain days, 7h sun
11°2°
December
5 rain days, 8h sun
3°-5°
Other Months in Seoul
Plan Your Trip to Seoul
Nearby Destinations
Cities within 500 km with comparable weather conditions
Data Sources for Seoul
Climate normals represent 30-year averages (1991-2020). Individual years may vary.