Weather in Busan 🇰🇷
Monthly weather averages & travel planning
September
Avg Temp
25°C
Rain Days
10 days
Sun Hours
8 hrs
Humidity
65%
Asia › 🇰🇷 South Korea › Busan
Updated: March 2026
Is September a Good Time to Visit Busan?
5/10
Fair
September is a fair time to visit Busan (5/10). With 8 daily sunshine hours and only 10 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 10th sunniest of the year in Busan. Culture-focused travellers and those who prefer lighter crowds will find September a practical choice, with prices running lower than peak April without sacrificing all the good weather. October offers a similar profile at lower hotel rates if dates are flexible. The main practical note: Busan's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: accommodation is generally available without long lead times, and flight prices are typically lower than peak season. Flexible travellers will find the best deals by booking 2-4 weeks ahead. Mid-week arrivals consistently unlock lower hotel rates than weekend check-ins.
vs August:28°C avg high
The single most important thing to know about visiting Busan in September: conditions are genuinely cooperative, with 25°C highs and only 10 wet days making this one of the more straightforward months to plan around. Precipitation totals 164mm for the month, spread across roughly 10 days, and 8 sunshine hours per day give you a reliable window for outdoor plans.
25°C
77°F
Avg High
20°C
68°F
Avg Low
10 days
164 mm total
Rain Days
8h
per day avg
Sunshine
65%
Moderate
Humidity
Temperature in Busan in September
The narrow 5°C gap between daytime and overnight temperatures, characteristic of coastal cities with maritime moderation, means a single mid-layer works across the whole day. Humidity averages 65%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 6 this month, classed as moderate. Sunscreen is a sensible precaution for extended outdoor time, particularly at midday. Wind averages 18 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 77°F average high, 68°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 Busan in September
Morning20°CBefore the day warms up
Afternoon25°CPeak daytime temperature
Evening23°CAfter sunset cools down
Packing for Busan in September means dressing for 25°C days and 20°C evenings. A light cotton tee with a casual overshirt works well at 25°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 20°C, a modest 5°C drop that a light cardigan or denim jacket covers. Comfortable walking trainers are the versatile choice for both outdoor sightseeing and indoor venues. A compact foldable umbrella weighs almost nothing and earns its keep across 10 potential rainy days. For temple and religious site visits, carry a lightweight scarf or sarong to cover shoulders and knees, required at most major sites across the region.
Local tip: Temple and religious site visits require covered shoulders and knees in most of Busan's heritage areas. A lightweight scarf or sarong weighs almost nothing and solves the problem instantly.
Events in Busan in September
September has no major festivals or public holidays in Busan, 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 Busan in September
Based on 25°C average highs and 10 rainy days
- Light layers for morning and evening
- Breathable T-shirts and comfortable trousers
- UV-protective sunglasses
- Compact folding umbrella
- Waterproof outer layer or packable rain jacket
- Quick-dry clothing that recovers fast after a shower
- SPF 30+ sunscreen
- 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 Busan in September
- Explore outdoor markets and street food stallsMid-morning (10am-12pm)At 25°C, the temperature is ideal for extended walking without overheating
- Guided walking tour of the historic centreMorning or late afternoonComfortable temperatures allow several hours on foot without fatigue
- Visit rooftop viewpoints and observation decksGolden hour (1 hour before sunset)Warm clear evenings provide exceptional visibility for panoramic photography
- Day trip to the surrounding countryside or coastFull day (depart by 8am)September is reliably dry enough for rural day trips without weather risk
- 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 morningSeptember brings distinct seasonal changes to public green spaces worth exploring
- Try the seasonal farmer's market for local produce and street foodSaturday morning markets typically 8am-1pmSeptember seasonal produce is at peak availability, offering dishes not found at other times of year
Why is Busan warm in September?
Busan's September heat is driven by the Asian summer monsoon system, as the low-pressure cell that forms over the heated landmass draws warm, humid air from the oceans. The result is temperatures averaging 25°C with high moisture in the air. Overnight temperatures remain elevated at 20°C, as clouds and humidity prevent the earth from radiating heat away after sunset. 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
Busan in September
In September, Busan experiences average highs of 25°C (77°F) and lows of 20°C (68°F). Expect around 10 rainy days and 8 hours of sunshine per day, with humidity averaging 65%. The 5°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 6, so sun protection is advisable on clear days.
Busan typically sees 10 rainy days in September, with total precipitation of around 164mm. Rain is moderate and manageable. Showers tend to pass quickly, and a light rain layer or foldable umbrella is sufficient protection for most days. For context, the driest month in Busan typically sees 4-6 fewer rain days than September.
Pack light layers, a light jacket for evenings, comfortable walking shoes, and sunscreen for Busan in September. Daytime temperatures of 25°C are pleasant, but the evening drop to 20°C means a jacket is essential if you plan to be out after dark. With 10 rainy days, bring a compact umbrella or waterproof jacket for unexpected showers. Comfortable walking shoes are a priority given the amount of ground most visitors cover.
Yes, September is an excellent time to visit Busan. With 8 daily sunshine hours and only 10 rainy days, conditions are ideal for sightseeing and outdoor activities. Temperatures averaging 25°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 Busan in September is 25°C (77°F), and the average low is 20°C (68°F). The mean daily temperature is approximately 23°C (73°F). The day-to-night range of 5°C is narrow, typical of coastal or maritime cities. 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 Busan is generally April. April offers the most sunshine at 10 hours per day and only 8 rainy days. Average temperatures reach 16°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.
September is shoulder or low season in Busan, meaning fewer tourists and generally lower prices than peak months. With 8 sunshine hours and 10 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 September, Busan suits a range of activities thanks to mild temperatures around 25°C. Mix of indoor and outdoor activities works well given the moderate chance of rain. 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.
September ranks 10th sunniest of the year in Busan, with an average 8 daily sunshine hours. The driest months are December, January, and February. August is the hottest month (28°C avg high); January is the coolest (6°C). From here, temperatures fall 5°C into October. Compared to last month (August: 28°C high, 14 rain days), September is cooler and drier. September 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 | 6°C | 0°C | 4 | 8h | View |
| February | 8°C | 1°C | 5 | 9h | View |
| March | 12°C | 5°C | 8 | 9h | View |
| April | 16°C | 10°C | 8 | 10h | View |
| May | 21°C | 14°C | 8 | 10h | View |
| June | 24°C | 18°C | 10 | 9h | View |
| July | 27°C | 22°C | 14 | 9h | View |
| August | 28°C | 24°C | 14 | 9h | View |
| September | 25°C | 20°C | 10 | 8h | View |
| October | 20°C | 14°C | 5 | 9h | View |
| November | 14°C | 8°C | 5 | 8h | View |
| December | 8°C | 2°C | 3 | 8h | View |
January
4 rain days, 8h sun
6°0°
February
5 rain days, 9h sun
8°1°
March
8 rain days, 9h sun
12°5°
April
8 rain days, 10h sun
16°10°
May
8 rain days, 10h sun
21°14°
June
10 rain days, 9h sun
24°18°
July
14 rain days, 9h sun
27°22°
August
14 rain days, 9h sun
28°24°
September
10 rain days, 8h sun
25°20°
October
5 rain days, 9h sun
20°14°
November
5 rain days, 8h sun
14°8°
December
3 rain days, 8h sun
8°2°
Other Months in Busan
Plan Your Trip to Busan
Nearby Destinations
Cities within 500 km with comparable weather conditions
Data Sources for Busan
Climate normals represent 30-year averages (1991-2020). Individual years may vary.