Best time to visit Ansan-si
The best time to visit Ansan-si is October, judged on twenty years of weather records and the events worth going for.
Ansan-si, Gyeonggi-do, South Korea
°C
mm
- Average daily high and low
- Precipitation
- Good month
- Best month
- Made good or best by an event
| Month | Average daily high | Average daily low | Precipitation | Verdict |
|---|---|---|---|---|
| January | 1.9 °C / 35 °F | -2.9 °C / 27 °F | 20 mm / 0.8 in | neither best nor good |
| February | 3.4 °C / 38 °F | -1.4 °C / 29 °F | 28 mm / 1.1 in | neither best nor good |
| March | 7.6 °C / 46 °F | 3 °C / 37 °F | 46 mm / 1.8 in | neither best nor good |
| April | 12.7 °C / 55 °F | 8.1 °C / 47 °F | 78 mm / 3.1 in | good month |
| May | 17.8 °C / 64 °F | 13.4 °C / 56 °F | 107 mm / 4.2 in | good month |
| June | 22.2 °C / 72 °F | 18.5 °C / 65 °F | 113 mm / 4.5 in | good month |
| July | 25.8 °C / 78 °F | 22.8 °C / 73 °F | 305 mm / 12 in | neither best nor good |
| August | 27.4 °C / 81 °F | 24.2 °C / 76 °F | 223 mm / 8.8 in | neither best nor good |
| September | 24.4 °C / 76 °F | 20.2 °C / 68 °F | 133 mm / 5.3 in | good month |
| October | 18.8 °C / 66 °F | 13.9 °C / 57 °F | 69 mm / 2.7 in | best month |
| November | 11.8 °C / 53 °F | 6.7 °C / 44 °F | 58 mm / 2.3 in | good month |
| December | 4.4 °C / 40 °F | -0.7 °C / 31 °F | 32 mm / 1.2 in | neither best nor good |
Good and best months depend on more than temperature, rain and events. How they are chosen
Each activity on this page has its own good and best months, rated on twenty years of daily weather records. Which measures count, and how much, depends on the activity: humidity for exploring outdoors, wind for the beach, hiking and skiing, snow for skiing alone. Between them, the activities are rated on:
- Daytime highs
- Night-time lows
- How warm it feels
- Humidity
- How much of the day is sunny
- Hours of daylight
- Monthly rainfall
- How many days it rains
- Days of heavy rain
- Wind
- Snowfall and days with snow
- Major events, such as festivals
The chart shows the good and best months for exploring outdoors.
The event icon marks a month that an event lifts to good or best, such as a festival or a natural spectacle. Choose “Weather only” in the toolbar to rate the months on weather alone.
Best months by activity
Exploring outdoors
Mild days and nights, mostly dry and bright. The default for 'when should I go'.
- JJanuary: neither
- FFebruary: neither
- MMarch: neither
- AApril: good
- MMay: good
- JJune: good
- JJuly: neither
- AAugust: neither
- SSeptember: good
- OOctober: best
- NNovember: good
- DDecember: neither
- Best
- October
- Good
- April–June, September, November
Winters (Dec-Mar) are too cold for comfortable exploring, and the summer monsoon (Jul-Aug) brings heavy, humid rain that overwhelms the outdoors. April through June and September are good despite periodic rain and, in June, high humidity; October is the best month, mild, dry and sunny, with November a cooler but still good fallback.
Why these months
April · good
In its favour: share of daylight that is sunny 75%, days with heavy rain 2.9 days, average daily low 8.1 °C / 47 °F, relative humidity 74%.
Against: precipitation 78 mm / 3.1 in, wet days 7.6 days, feels like (high) 10.7 °C / 51 °F, average daily high 12.7 °C / 55 °F.
May · good
In its favour: feels like (high) 17.6 °C / 64 °F, share of daylight that is sunny 72%, average daily high 17.8 °C / 64 °F, average daily low 13.4 °C / 56 °F.
Against: precipitation 107 mm / 4.2 in, days with heavy rain 3.2 days, wet days 7.4 days, relative humidity 78%.
Also on: Ansan Street Arts Festival, Seongho Cultural Festival.
June · good
In its favour: feels like (high) 24.4 °C / 76 °F, average daily high 22.2 °C / 72 °F, share of daylight that is sunny 70%, average daily low 18.5 °C / 65 °F.
Against: relative humidity 83%, precipitation 113 mm / 4.5 in, days with heavy rain 3.1 days, wet days 7.8 days.
Also on: Ansan Yeoremio Festival.
September · good
In its favour: feels like (high) 26.2 °C / 79 °F, average daily high 24.4 °C / 76 °F, share of daylight that is sunny 69%, average daily low 20.2 °C / 68 °F, relative humidity 75%.
Against: precipitation 133 mm / 5.3 in, days with heavy rain 3.8 days, wet days 7.8 days.
Watch out for: Chuseok closures.
October · best
In its favour: feels like (high) 17.7 °C / 64 °F, average daily high 18.8 °C / 66 °F, share of daylight that is sunny 79%, days with heavy rain 2.1 days, average daily low 13.9 °C / 57 °F, relative humidity 70%.
Against: precipitation 69 mm / 2.7 in, wet days 6.2 days.
Watch out for: Chuseok closures.
November · good
In its favour: share of daylight that is sunny 76%, days with heavy rain 1.4 days, relative humidity 69%, average daily low 6.7 °C / 44 °F.
Against: feels like (high) 8.7 °C / 48 °F, wet days 7.9 days, precipitation 58 mm / 2.3 in, average daily high 11.8 °C / 53 °F.
An activity is listed only where it applies: skiing at ski destinations, beach and swimming at beach destinations. The nearest ski area is 곤지암스키장, Konjiam Resort, 40 km away.
Weather averages
Monthly averages over twenty years, 2006–2025. Highs, lows and precipitation are in the chart at the top.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Feels like (high) | -2.8 °C | -1.1 °C | 4.3 °C | 10.7 °C | 17.6 °C | 24.4 °C | 29.9 °C | 32.1 °C | 26.2 °C | 17.7 °C | 8.7 °C | 0 °C |
| Days with heavy rain | 0.3 days | 0.8 days | 1.2 days | 2.9 days | 3.2 days | 3.1 days | 7.4 days | 6 days | 3.8 days | 2.1 days | 1.4 days | 0.7 days |
| Time rain usually falls | 8 pm | 10 am | 2 am | 7 am | 5 am | 12 am | 7 am | 8 am | 3 am | 9 am | 3 am | 2 pm |
| Sunshine per day | 8 h | 8.6 h | 9.5 h | 9.9 h | 10.2 h | 10.2 h | 8.1 h | 9 h | 8.6 h | 8.9 h | 7.8 h | 7.6 h |
| Relative humidity | 66% | 68% | 72% | 74% | 78% | 83% | 88% | 84% | 75% | 70% | 69% | 68% |
Air quality
Averaged over a shorter period (2022–2025) than the twenty-year averages above, and not counted towards good or best months.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Air pollution (PM2.5) 2022–2025 | 32.6 µg/m³ | 28 µg/m³ | 32.2 µg/m³ | 31.7 µg/m³ | 29.7 µg/m³ | 28 µg/m³ | 22.9 µg/m³ | 27.9 µg/m³ | 23.6 µg/m³ | 25.3 µg/m³ | 28.6 µg/m³ | 26.9 µg/m³ |
| Air pollution (PM2.5, daily peak) 2022–2025 | 56.6 µg/m³ | 46.5 µg/m³ | 49.4 µg/m³ | 49.2 µg/m³ | 45.7 µg/m³ | 42.6 µg/m³ | 39.3 µg/m³ | 46.6 µg/m³ | 39.8 µg/m³ | 41.6 µg/m³ | 50.2 µg/m³ | 49.9 µg/m³ |
- Good 15 µg/m³ or less
- Fair 15 to 25 µg/m³
- Moderate 25 to 37.5 µg/m³
- Poor 37.5 to 50 µg/m³
- Very poor 50 to 75 µg/m³
- Extremely poor over 75 µg/m³
Each figure is compared with the World Health Organization's guideline for a day's air, 15 µg/m³ or less, and with its interim targets above that. The words are ours: the WHO does not name its steps. The figures are modelled monthly averages, so single days can be well above them. The daily peak is the average of each day's highest hour, shaded on the same scale.
Events and seasons
What the weather records cannot show. A major event can lift a month to good or best. The warnings are there to help you plan, and never count against a month.
Reasons to go
- Ansan Street Arts Festival
May
- Seongho Cultural Festival
May
- Ansan Yeoremio Festival
June, July and August
- Ansan (M) Valley Rock Festival
July
Worth knowing before you go
- Lunar New Year (Seollal) closures
January and February, dates vary from year to year
- Chuseok closures
September and October, dates vary from year to year
World Heritage sites nearby
UNESCO World Heritage sites within 25 km, nearest first.
- Hwaseong Fortress
17 km away