The climate of Seoul
Notably situated within the Köppen climate zone,
Seoul,
South Korea is characterized by a Humid Continental climate with a twist—this city experiences a severe dry winter and a hot summer, classified as Dwa in the Köppen classification. This geographical location lends itself to vast fluctuations in temperature from extreme cold in winter months to sweltering heat during the summer.
Over the course of a year, the city sees average high temperatures ranging from a frosty 1.5°C (34.7°F) in the first month of the year to a sun-stricken 29.6°C (85.3°F) at the peak of summer in
August. Correspondingly, the low temperatures follow a similar pattern, with mercury dipping to -5.9°C (21.4°F) in
January and reaching a nighttime high of 22.4°C (72.3°F) in August.
Relative humidity levels follow a distinct annual cycle, with moderate conditions between 56.2% and 78.3%. Rainfall ranges broadly from 21mm (0.83") in January, with no more than 6.5 rainy days, to a flood-inducing 395mm (15.55") over 16.3 days in
July. However, the daily sunshine duration and UV index reflect the amount of solar energy reaching the city's surface, both of which peak during the summer months.
The best time to visit Seoul
Considering the sunshine hours, moderate temperature, and relative humidity, the prime time for tourism in
Seoul would arguably be from late spring to early summer, specifically from
April to
June. During this period, high temperatures are comfortably nestled between 10.4°C (50.7°F) and 23°C (73.4°F). Correspondingly, rainfall is moderate compared to the rest of the year, progressing from 47mm (1.85") to 106mm (4.17"), while the number of rainy days ramps up from 7.4 to 9.0.
In addition, these months boast a robust 12 to 14.2 hours of daylight, allowing visitors to make the most of their day. Sunlight exposure is balanced with a UV index between 5 and 8 - not so low to prevent a lovely summer glow, nor too high to expose tourists to harmful ultraviolet radiation.
The worst time to visit Seoul
Avoid
July and
August if possible when planning a visit to
Seoul. These months experience the highest temperatures, peaking between 28.6°C (83.5°F) and 29.6°C (85.3°F). The muggy heat is exacerbated by the relative humidity, which soars to 78.3% and 75.6%, respectively. Last but not least, these momentous deluges bring a washout average of 395mm (15.55") and 364mm (14.33") rainfall in July and August. Coupled with an oppressive UV index of 10 and 9, these factors make Seoul less favorable for outdoor activities.
Spring weather in Seoul
Spring descends between
March and
May, marking a refreshing escape from the clinging cold of winter. During this period, average high temperatures climb from 10.4°C (50.7°F) to 23°C (73.4°F), making way for the blossoms to flourish. Correspondingly, low temperatures emerge from the freezing mark to a comfortable 13.2°C (55.8°F), pointing to milder nights and early mornings. As much as 47mm (1.85") to 106mm (4.17") rainfall can be expected, providing ample moisture for the blooming season.
Summer weather in Seoul
From
June to
August,
Seoul dives into a sizzling hot summer. The average high temperature flares between 23°C (73.4°F) and 29.6°C (85.3°F), while the minimum temperature floats around 18.2°C (64.8°F) to 22.4°C (72.3°F). However, summer is also the rainiest season in Seoul, with downpours reaching from 133mm (5.24") in June to a staggering 395mm (15.55") in
July, dipping slightly to 364mm (14.33") in August. Amidst this, the city grapples with maximum relative humidity and UV index levels, making for steamy days and sticky nights.
Autumn weather in Seoul
September ushers in a pleasant autumn. The season is characterized by gradually receding temperatures from 25.8°C (78.4°F) to a modest 11.6°C (52.9°F) by
November. Simultaneously, rainfall decreases from a sizeable 169mm (6.65") in September to a mere 53mm (2.09") by November, marking drier and clear days. Relative humidity and UV index levels also drop, offering a much-needed reprieve after the brutal summer months.
Winter weather in Seoul
From
December to
February,
Seoul is in the icy grip of winter. High temperatures skid down from a chilling 4.3°C (39.7°F) in December to a bone-chilling 1.5°C (34.7°F) in
January, before rising marginally in February. The mercury plummets further at night, with lows oscillating from -3.2°C (26.2°F) to -5.9°C (21.4°F). Yet, in the heart of this severe winter, Seoul remains relatively dry and with fewer daylight hours, reducing the likelihood of snowfall.
Weather in January
January in
Seoul,
South Korea is predominantly dry and consists of long, cold nights with low temperatures descending to -5.9°C (21.4°F). Frozen snowflakes frequently decorate the scenic landscapes, creating a wintry atmosphere.
Weather in January » Weather in February
February displays a continuation of the winter climate, with cold conditions prevailing. Snowfall is still possible, adding to the charm of
Seoul's architectural treasures. The Level 2 UV index implies that snow blindness could be an issue for those outside during sunny days.
Weather in February » Weather in March
March acts as a bridge between winter and spring, with temperatures ranging from -3.4°C (25.9°F) to 10.4°C (50.7°F). The soft spring breeze brings a sense of renewal to
Seoul, as colorful flowers start blooming around the city.
Weather in March »
Weather in April
April witnesses a significant transition towards warm weather, with
Seoul's landscapes transforming into vibrant canvases of cherry blossoms. Ideal for outdoor activities, the climate is comfortably warm, experiencing soft, refreshing rain showers.
Weather in April » Weather in May
May is marked by
Seoul's rapid transition into summer, with more daylight hours and increasingly warm temperatures. Gardens are in full bloom and street festivals become more frequent and vibrant. Visitors and locals can enjoy outdoor dining and afternoon strolls in parks.
Weather in May » Weather in June
June showcases the arrival of summer in
Seoul, with hot, humid, and rainy conditions becoming the norm. People can be seen enjoying ice creams and cold drinks to ward off the heat. Nature enthusiasts will appreciate the lush greenery in parks and along the Han River.
Weather in June »
Weather in July
July is mostly characterized by
Seoul's hot and humid conditions due to the monsoon season. Raincoats and umbrellas become essential items for residents and tourists alike. Despite the heat, traditional summer celebrations continue with enthusiasm.
Weather in July » Weather in August
August maintains the peak of summer in
Seoul, with sultry weather and intense rain showers. It is a typical sight to see locals sipping on cold buckwheat noodles to keep cool. Outdoor enthusiasts will relish in the magnificent sunsets along the Han River despite the high humidity.
Weather in August » Weather in September
September ushers in the autumn spirit as it transitions from the sweltering summer. The city starts radiating hues of gold and brown, marking the beginning of fall. The comfortable autumn days make it a popular month for touring the city's cultural landmarks.
Weather in September »
Weather in October
October is famous for offering the best of
Seoul’s autumn weather, with mild temperatures and low rainfall. The city boasts vibrant and colorful foliage, offering beautiful panoramas, especially the panoramic view from Namsan Tower.
Weather in October » Weather in November
November, the last month of the autumn in
Seoul, is cool month, with an average temperature varying between 11.6°C (52.9°F) and 3.2°C (37.8°F). November's arrival is marked by a significant decrease in the average high-temperature, moving from a comfortable 19.8°C (67.6°F) in
October to a cool 11.6°C (52.9°F).
Weather in November » Weather in December
December marks the advent of winter, with temperatures diving into chilly lows. The streets are adorned with warm festive decorations, lighting up
Seoul's winter spell. Hot street food serves as the city’s defense against the falling mercury.
Weather in December »