Ulsan climate
Ulsan (South Korea) has a humid subtropical climate (Köppen Cfa). The average temperature over the year is 15 °C59 °F, and about 1,322 mm52 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Ulsan climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 643 | 032 | 338 | 421.7 | 15 |
| Feb | 847 | 236 | 541 | 532.1 | 9 |
| Mar | 1254 | 541 | 947 | 742.9 | 2 |
| Apr | 1762 | 1049 | 1356 | 1124.4 | 0 |
| May | 2169 | 1457 | 1763 | 1184.6 | 0 |
| Jun | 2475 | 1965 | 2170 | 1505.9 | 0 |
| Jul | 2780 | 2373 | 2576 | 2409.4 | 0 |
| Aug | 2883 | 2476 | 2679 | 1947.7 | 0 |
| Sep | 2576 | 2169 | 2373 | 1686.6 | 0 |
| Oct | 2069 | 1559 | 1864 | 763.0 | 0 |
| Nov | 1558 | 948 | 1253 | 542.1 | 0 |
| Dec | 847 | 236 | 541 | 421.7 | 10 |
| Year | 2883 | 032 | 1559 | 1,32252 | 37 |
“Year” row: highest monthly high, lowest monthly low, annual mean and annual total. Frost days are for the whole grid cell.
| Month | Humid. | Cloud | Solar | Daylight |
|---|---|---|---|---|
| Jan | 76% | 55% | 2.6 | 10:00 |
| Feb | 71% | 60% | 3.2 | 10:51 |
| Mar | 71% | 57% | 4.1 | 11:52 |
| Apr | 73% | 58% | 4.9 | 13:03 |
| May | 77% | 62% | 5.4 | 14:01 |
| Jun | 82% | 73% | 4.9 | 14:33 |
| Jul | 87% | 73% | 4.6 | 14:20 |
| Aug | 84% | 66% | 4.7 | 13:29 |
| Sep | 80% | 67% | 3.8 | 12:21 |
| Oct | 73% | 54% | 3.5 | 11:13 |
| Nov | 72% | 51% | 2.7 | 10:14 |
| Dec | 76% | 52% | 2.4 | 9:46 |
Humid. = average relative humidity at 2 m; cloud = average cloud amount; solar = average daily solar energy reaching the ground in kWh/m² (all-sky); daylight in hours:minutes, calculated for the 15th of each month.
What the climate of Ulsan is like
The warmest month is August, with an average high of 28 °C83 °F and a low of 24 °C76 °F. The coldest is January, when highs average 6 °C43 °F and lows 0 °C32 °F. Seasons are strongly marked: the warmest month is on average 23.1 °C41.6 °F warmer than the coldest.
It is wet, with about 1,322 mm52 in of precipitation per year. The wettest three-month stretch is July–September, which brings 46% of the annual total. The wettest month is July (240 mm9.4 in), the driest is December (42 mm1.7 in).
Relative humidity ranges from 71% in March to 87% in July. The clearest skies (lowest average cloud amount, 51%) are typical of November. Average wind speed near the ground ranges from 12 km/h (8 mph) in June to 20 km/h (12 mph) in January. Daylight lasts from about 9.8 hours in December to 14.5 hours in June.
Best time to visit Ulsan
Based on these averages, the most comfortable months for sightseeing and outdoor activities are October: average highs of 20 °C69 °F to 20 °C69 °F with 76 mm3.0 in to 76 mm3.0 in of precipitation per month.
The most challenging month is January, which is cold, with average highs of 6 °C43 °F.
Comfort score: months are ranked by how close they come to an average high of 21–28 °C (70–82 °F), lows above 5 °C (41 °F), little precipitation and moderate humidity. The best-ranked months of each place are recommended, even where none meets all of these. These are general rules of thumb applied to long-term averages.
What to pack for Ulsan
- Winter (December–February) — highs 643 to 8 °C47 °F, lows 032 to 2 °C36 °F, about 46 mm1.8 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Spring (March–May) — highs 1254 to 21 °C69 °F, lows 541 to 14 °C57 °F, about 101 mm4.0 in of precipitation a month. Pack long sleeves, a sweater and a medium jacket and an umbrella or light rain jacket.
- Summer (June–August) — highs 2475 to 28 °C83 °F, lows 1965 to 24 °C76 °F, about 195 mm7.7 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and an umbrella or light rain jacket.
- Autumn (September–November) — highs 1558 to 25 °C76 °F, lows 948 to 21 °C69 °F, about 99 mm3.9 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an umbrella or light rain jacket.
How Ulsan compares
Compared with Busan, about 55 km to the southwest, Ulsan is on average 0.3 °C0.6 °F warmer and receives 11% less precipitation (1,322 mm52 in vs 1,488 mm59 in). The difference is largest in November (0.7 °C1.2 °F warmer).
Of the 34 places in South Korea covered by World Climates, Ulsan is the 3rd warmest by annual mean temperature and the 12th wettest by annual precipitation. See all of them on the South Korea climate page.
Places in other countries with the most similar temperature and rainfall pattern: Mito (Japan, Cfa), Shunan (Japan, Cfa) and Kumagaya (Japan, Cfa).
Nearby places
- Yangsan 34 km · 13 °C56 °F · 1,342 mm53 in
- Gijang 34 km · 16 °C61 °F · 1,520 mm60 in
- Gyeongju 35 km · 14 °C57 °F · 1,186 mm47 in
- Pohang 55 km · 14 °C58 °F · 1,186 mm47 in
- Busan 55 km · 14 °C58 °F · 1,488 mm59 in
- Changwon 67 km · 14 °C58 °F · 1,488 mm59 in
- Daegu 75 km · 12 °C54 °F · 1,201 mm47 in
- Geoje 98 km · 14 °C58 °F · 1,488 mm59 in
Frequently asked questions
What is the warmest month in Ulsan?
August is the warmest month in Ulsan, with an average high of 28 °C (83 °F) and an average low of 24 °C (76 °F).
What is the coldest month in Ulsan?
January is the coldest month, with an average high of 6 °C (43 °F) and an average low of 0 °C (32 °F).
When does it rain the most in Ulsan?
July is the wettest month with about 240 mm (9.4 in) of precipitation; December is the driest with about 42 mm (1.7 in).
What is the best time to visit Ulsan?
Judging by long-term averages, the most comfortable months are October.
About this data
All figures are 25-year averages (January 2001 – December 2025) from the NASA POWER project. Temperature, humidity, wind and precipitation come from the MERRA-2 reanalysis (precipitation is the bias-corrected MERRA-2 product), cloud and solar values from CERES satellite data. They describe a grid cell of roughly 50–70 km, not a single weather station, so they can differ from airport records — most of all on coasts, in mountains and for rainfall. Average highs and lows are the monthly mean temperature plus/minus half of the average daily temperature range. Counts of rainy days are not part of this dataset.
The grid cell’s average elevation is 67 m, while Ulsan lies at about 10 m. Temperatures on this page were therefore adjusted by +0.4 °C0.7 °F using the standard lapse rate of 6.5 °C per 1,000 m.