TL;DR — 3 things to know before you land
- Seoul's rainy season normally runs from about June 25 to July 26. In 2026 it started late, on July 1, and the Korea Meteorological Administration (KMA) provisionally judged it over on July 26. Rain comes in bursts, not nonstop, and heavy showers can still hit after the season officially ends.
- Two spas that older guides still recommend are closed. Dragon Hill Spa in Yongsan has not reopened since it shut in 2021, and Siloam Sauna near Seoul Station no longer operates. HYBE Insight and SMTOWN COEX Artium are gone too, so check that a place is open before you go.
- Seoul still has plenty of dry options. The National Museum of Korea is free in 2026 and stays open late on Wednesdays and Saturdays, Starfield Library at COEX is free, and aquariums, Lotte World Adventure, Nanta and 24-hour jjimjilbang fill the rest of a wet day.
☔ Heavy Rain Alerts — What Changes
Ordinary jangma rain rarely ruins a trip, but a heavy rain advisory (호우특보) is different.
• National park trails such as Bukhansan and Seoraksan are closed during weather advisories. Seoraksan's high trails were closed again on June 20, 2026.
• Low-lying areas can flood fast. The Gangnam Station area flooded in August 2022, when more than 100 mm of rain fell in an hour. If an alert tells you to avoid underground spaces, leave underground malls and passages.
• Riverside Han River parks sit low and have been closed during floods. All 11 were shut in August 2020.
Emergency alerts arrive in Korean. Since June 15, 2026, the government's Emergency Ready app translates disaster texts into 22 languages, and the most urgent alerts also show key words such as the disaster type in English.
• National park trails such as Bukhansan and Seoraksan are closed during weather advisories. Seoraksan's high trails were closed again on June 20, 2026.
• Low-lying areas can flood fast. The Gangnam Station area flooded in August 2022, when more than 100 mm of rain fell in an hour. If an alert tells you to avoid underground spaces, leave underground malls and passages.
• Riverside Han River parks sit low and have been closed during floods. All 11 were shut in August 2020.
Emergency alerts arrive in Korean. Since June 15, 2026, the government's Emergency Ready app translates disaster texts into 22 languages, and the most urgent alerts also show key words such as the disaster type in English.
What is Jangma (Korea's Monsoon Season)?
A rain front that moves north from Jeju to Seoul. The dates change every year.
Jangma (장마) is the summer rainy season caused by a stationary front over the Korean Peninsula. It reaches Jeju first, then the south, then central Korea, which includes Seoul. Rain usually comes in rounds, with a heavy burst followed by hours of cloud and humidity, and some days stay dry.
| Region | Normal season (1991–2020 average) | 2026 (KMA, provisional) |
|---|---|---|
| Jeju | June 19 – July 20 (about 32 days) | June 30 – July 19 (20 days) |
| Southern Korea | June 23 – July 24 (about 31 days) | June 30 – July 25 (26 days) |
| Central Korea incl. Seoul | June 25 – July 26 (about 31 days) | July 1 – July 26 (26 days) |
KMA calls these dates provisional and confirms the start and end after the summer is over. In 2026 the season started late but ended close to the usual date, so it was shorter than normal. When jangma ends, heat and humidity take over, and short, heavy showers can still happen in August.
Plan by the forecast, not the calendar. Check KMA's English forecast a few days before you travel, then the hourly forecast the night before. Summer rain in Korea can arrive within an hour.
What to Pack — and What to Skip
Light, quick-drying and cheap to replace beats heavy and "waterproof".
Pack These
✓ Compact folding umbrella
It takes up almost no space and handles sudden downpours better than a hood. If you forget one, convenience stores (CU, GS25, 7-Eleven) sell clear vinyl umbrellas. Expect roughly ₩5,000–₩8,000.
✓ Packable poncho or thin rain jacket
A heavy raincoat traps heat in humid summer air. A light poncho keeps you dry between subway exits and entrances without overheating.
✓ Shoes that dry fast
Canvas sneakers stay wet for a long time after one downpour. Sport sandals, slip-ons or water-resistant trainers handle puddles at crosswalks and station entrances better.
✓ Quick-dry clothing
Damp clothes dry slowly in high humidity. Pack fewer heavy cotton items, and on a longer trip plan a stop at a coin laundry.
✓ Waterproof pouch for your phone and passport
A sudden downpour can soak a bag before you find cover.
Don't Bother
SKIP Bulky waterproof raincoat
Non-breathable coats trap heat and sweat, so you end up damp anyway. A thin poncho breathes better.
SKIP Large golf umbrella
It is awkward on crowded pavements and subway stairs. A compact one works just as well.
SKIP A week's worth of cotton clothing
Cotton stays damp. Pack less, plan one laundry stop and lean on quick-dry fabrics.
Best Indoor Activities in Seoul
Hours, prices and closures below were checked in October 2026. They change, so check the official site before you go.
| Place | Where | What we checked (Oct 2026) |
|---|---|---|
| National Museum of Korea | Yongsan, near Ichon Station (Line 4, Gyeongui–Jungang Line) | Permanent galleries free. Open 9:30–17:30, until 21:00 on Wednesdays and Saturdays. Closed only on January 1, Seollal and Chuseok; the galleries also close on a few set Mondays (December 7 is the last one in 2026). Paid admission is planned from 2027. |
| Leeum Museum of Art | Hannam-dong, Yongsan | Tuesday–Sunday 10:00–18:00, closed Mondays. The Korean antiquities permanent exhibition is free; special exhibitions charge. Booking ahead is recommended, but walk-up tickets are sold. |
| National Folk Museum of Korea | Inside the Gyeongbokgung Palace grounds | Free, no reservation. March–October 9:00–18:00. Permanent Exhibition Hall 1 is closed from September 30 to December 21, 2026 (planned). Expect a short outdoor walk inside the palace grounds. |
| Starfield COEX Mall & Starfield Library | Samseong Station (Line 2) | The library is free and open 10:30–22:00 every day. The mall connects to the station underground. |
| SEA LIFE COEX Aquarium (formerly COEX Aquarium) | COEX Mall | 10:00–20:00, last entry 19:00. Adult list price ₩35,000; ₩28,000 online when we checked. |
| Lotte World Adventure | Jamsil Station (Line 2, Line 8) | A large indoor park plus the outdoor Magic Island. Adult one-day pass ₩67,000 since April 1, 2026. |
| Lotte World Aquarium | Lotte World Mall, Jamsil | Adult list price ₩35,000 in 2026 listings; online and card discounts are common. |
| Nanta | Theaters in Myeongdong and Hongdae | Non-verbal kitchen-percussion show, still running in 2026. Book ahead. |
| Department stores & underground shopping | Shinsegae, Hyundai, Lotte; underground shops at Express Bus Terminal and Gangnam Station | Food halls and cafes, with hours that vary by store. During a heavy rain alert, see the warning above about underground spaces. |
No Longer Open — Still on Older Lists
CLOSED Dragon Hill Spa (Yongsan)
Went into a temporary closure in 2021 and has not reopened.
CLOSED Siloam Sauna (near Seoul Station)
No longer operating; travel listings mark it as permanently closed.
CLOSED HYBE Insight (Yongsan)
The museum closed on January 15, 2023. In March 2026 HYBE opened a pop-up store in its Yongsan lobby instead.
CLOSED SMTOWN COEX Artium
Closed in 2020. The Artium building is now a performance hall.
Ride, don't walk. The Seoul subway base fare with a T-money card is ₩1,550 for up to 10 km. COEX Mall and Lotte World both connect to their stations underground, so you can get from the train to the attraction without going outside.
Jjimjilbang — Still a Rainy-Day Favorite
Korea's bathhouse and sauna combo works well on a wet afternoon. Just pick one that is actually open.
A jjimjilbang combines gender-separated baths, mixed heated rooms where everyone wears the provided uniform, rest areas and a snack bar. Adult entry in Seoul generally falls around ₩10,000–₩20,000 in 2026, and some places charge more at night.
What to Know Before You Go
✓ Example that was open in 2026: Spa Rex Dongdaemun
Open 24 hours on basement level 3 of the Goodmorning City building, next to exit 13 of Dongdaemun History & Culture Park Station. A visitor reported ₩16,000 for adults in April 2026. Check the price at the counter.
✓ Baths are nude and separated by gender
Shower before you get into the baths. The heated rooms and lounges are shared, and everyone wears the uniform you get at the front desk.
✓ Bring spare underwear
Towels and the uniform usually come with entry, but underwear does not.
Outdoor Plans to Reschedule or Skip
Keep these flexible instead of locking them to a fixed date.
| Plan | Risk in the rainy season | Better approach |
|---|---|---|
| Bukhansan / Seoraksan hiking | Trails close during weather advisories; wet rock is slippery | Check the Korea National Park Service trail-control notice on the morning you go. |
| Han River parks | Low-lying riverside areas close during floods | Treat a picnic as a bonus for a dry evening. |
| Palace grounds | Mostly outdoors | Go between rain bands, and pair Gyeongbokgung with the National Folk Museum on its grounds. |
| DMZ tours | Tours can be cancelled for bad weather or security reasons | Book with a clear cancellation policy and keep an indoor backup for that day. |
| Rooftop bars and viewpoints | Outdoor seating may close in heavy rain | Keep it as a spontaneous plan, not a fixed booking. |
Front-load, don't cancel. On a week-long trip, put outdoor-heavy days early and keep one or two flexible days near the end. A rained-out morning then means swapping days, not losing the plan.
How Locals Handle the Rain
Rain gear is cheap and easy to replace in Seoul.
When rain catches people out, they buy an umbrella at the nearest convenience store. CU, GS25 and 7-Eleven all stock umbrellas and ponchos. CU advertised its 55 cm vinyl umbrella at about ₩5,000 in 2024, and GS25 listed a 60 cm vinyl umbrella at ₩7,500 in 2026.
Many shops, restaurants and department stores put plastic umbrella sleeves by the door so wet umbrellas don't drip on the floor. Seoul's public buildings and subway stations stopped using plastic sleeves in May 2018 and use rain-shaker stands instead.
Shake, sleeve, then step in. Use the sleeve or shaker stand at the entrance before you walk in with a wet umbrella.
Frequently Asked Questions
In central Korea, which includes Seoul, it normally runs from about June 25 to July 26 (1991–2020 average). In 2026 it started on July 1, and KMA provisionally judged it over on July 26. Rain comes in bursts, and short heavy showers can still happen in August, so check the forecast a few days ahead and the hourly forecast the night before.
No. Dragon Hill Spa in Yongsan went into a temporary closure in 2021 and has not reopened, and Siloam Sauna near Seoul Station no longer operates. Spa Rex in Dongdaemun is one 24-hour jjimjilbang that was operating in 2026. Check before you go.
Yes, the permanent galleries are free in 2026, though some special exhibitions charge. The government plans to start charging admission in 2027. Reports in September 2026 put the adult price at around ₩5,000–₩10,000, with the start month still undecided.
Bring a compact umbrella, a light poncho or thin rain jacket, quick-drying clothes and shoes, and a waterproof pouch for your phone and passport. If you forget an umbrella, convenience stores sell vinyl ones for roughly ₩5,000–₩8,000.
Install the Emergency Ready app, which translates Korean disaster texts into 22 languages. Stay off mountain trails and out of riverside parks. If the alert tells you to avoid underground spaces, leave underground malls and passages, especially in low-lying areas such as around Gangnam Station.
Sources (checked October 25, 2026)
- KMA via Yonhap/Chosun Biz (July 27, 2026): 2026 jangma ended July 19 (Jeju), July 25 (south) and July 26 (central), provisional; News1 (July 27, 2026): 2026 lengths of 20/26/26 days and 1991–2020 normals of 32.4/31.4/31.5 days
- KBS (July 1, 2026): central Korea start on July 1; Vegannews (July 9, 2026): Jeju and south started June 30; Kookje (July 27, 2026) and Karnews: normal start and end dates
- National Museum of Korea official visitor information (museum.go.kr): hours, free admission, 2026 closures; Financial News (September 1, 2026): paid admission from 2027, adult price expected ₩5,000–₩10,000
- Leeum Museum of Art official visit page (leeumhoam.org): hours, Monday closure, free permanent exhibition, booking
- National Folk Museum of Korea official site (nfm.go.kr): free admission, hours, Permanent Exhibition Hall 1 closure
- VisitSeoul: Starfield Library hours and free entry; SEA LIFE COEX official ticketing page: hours and prices
- Industry News (March 16, 2026): Lotte World Adventure ₩67,000 from April 1, 2026; 2026 listings (February and May 2026): Lotte World Aquarium ₩35,000 adult
- EconoVill (July 5, 2026): Nanta running at Myeongdong, Hongdae and Jeju theaters
- Namu Wiki (October 2026) and closure notices: Dragon Hill Spa; Tripadvisor and LUWEI (August 9, 2026): Siloam Sauna closed
- HYBE INSIGHT official X post (January 2023) and NC Press (March 23, 2026); 2026 report: SMTOWN COEX Artium closed in 2020
- Visitor blog posts (April 2026) and Klook/Trazy listings: Spa Rex Dongdaemun, 24 hours, location and price; Trip.com and Lveden (July 2026): Seoul jjimjilbang price range
- Korea.kr and KMCN (2026): Emergency Ready app in 22 languages from June 15, 2026; Ministry of the Interior and Safety (February 28, 2024): English key words in urgent alerts
- Yonhap (August 9, 2022): Gangnam Station flooding; Newspim (August 4, 2020): all 11 Han River parks closed; Yonhap (June 20, 2026): Seoraksan trails closed
- Paju DMZ Peace Tourism visitor guide: tours may be cancelled for security threats or bad weather
- Yonhap (June 18, 2024): CU vinyl umbrella at about ₩5,000; cvsprice (August 2026): GS25 60 cm vinyl umbrella ₩7,500; Seoul Metropolitan Government (April 23, 2018): plastic umbrella sleeves removed from public buildings and subway stations from May 1, 2018
- Inner Korea subway app guide: Seoul subway base fare ₩1,550 (T-money, up to 10 km)