Seoul Weather

April is Seoul's peak season — cherry blossoms in full bloom. Yeouido Park (Yunjungno Road), Seokchon Lake, Children's Grand Park (1,400+ trees), and Bukhansan National Park all reach maximum bloom in early-to-mid April. Yeouido Cherry Blossom Festival (early-to-mid April) is THE event. The 5km Yunjungno Road becomes pedestrian-only for the festival; nighttime illumination of cherry blossoms is genuinely magical. Free entry; food trucks and cultural performances throughout. Weather is mild (15-22°C / 59-72°F daytime) and dry — ideal for walking. Outdoor cafés and Han River parks all reopen. Late April begins the K-Pop event season — many fan meetings, concerts, and showcases happen. The trade-off is crowds and prices. Hotels are 50-100% above normal, often fully booked. Cherry blossom spots are extremely crowded weekends. Yeouido Park weekend gets 1+ million visitors. Book everything 6-8 weeks ahead. Day trips to Nami Island (Winter Sonata K-drama) and Jeonju Hanok Village (3h KTX) are at peak. Cherry blossom photography from N Seoul Tower is also iconic.

May is Seoul's most genuinely pleasant month — temperatures 22-25°C / 72-77°F days, 13-15°C evenings, low humidity (60-65%), longer daylight (sunset 7:35 PM). Outdoor culture peaks: Han River parks fill with picnics, late-night cafés open terraces. Buddha's Birthday (varies year to year — typically early-to-mid May) is a major Buddhist holiday. The Lotus Lantern Festival preceding the holiday illuminates Insadong, Jogyesa Temple, and the Cheonggyecheon Stream with 50,000+ traditional lanterns. The festival parade through Jongno is one of Asia's most beautiful religious events. Free public viewing. Children's Day (May 5) is a public holiday — Korean families fill amusement parks (Lotte World, Everland, Seoul Land), zoos, and beaches. Hotels in Gyeongju and beach areas spike. Seoul itself less affected. K-Pop concerts begin ramping up — many international tours kick off in Seoul. Major venues (Olympic Hall, Gocheok Sky Dome) host BTS, BLACKPINK, IU, NewJeans-level acts. Tickets sell out in minutes through fan-club lottery. May weather is genuinely peak. Cherry blossoms gone but azaleas and roses bloom. Late May begins humidity creep toward summer. Hotel prices remain at spring peak.

October is Seoul's most photogenic month. Cherry blossoms have their April moment, but October's autumn foliage at Bukhansan National Park (within Seoul), Naejangsan (3h south), and Mt. Seorak (3h east) creates the most dramatic landscapes Korea has to offer. Cheonggyecheon Stream Lantern Festival (mid-October to early November) installs massive light displays along 1.5km of restored urban stream. Free entry; runs 17:00-23:00 daily. The most underrated Seoul cultural event for international visitors. Combines well with autumn foliage at Namsan. Autumn foliage in Seoul itself peaks late October at Namsan (around N Seoul Tower), Changdeokgung Palace's secret garden, and Bukhansan National Park. Day trips to Mt. Seorak (KTX + bus, 3h) for the iconic Korean autumn experience. Open House Seoul (mid-October, varies year to year) opens normally-closed historic homes, embassies, and architecturally significant buildings to free public tours. Genuinely unique behind-the-scenes Seoul experience. Weather is ideal for walking — mild daytime (17-20°C / 63-68°F), cool but not cold mornings/evenings (9-12°C / 48-54°F). Lower humidity than spring or summer. Hotel prices match April peak.