Shunan climate
Shunan (Japan) has a humid subtropical climate (Köppen Cfa). The average temperature over the year is 15 °C58 °F, and about 1,696 mm67 in of precipitation falls in an average year.
Temperature by month
Precipitation by month
Shunan climate table
| Month | High °C°F | Low °C°F | Mean °C°F | Precip. mmin | Frost days |
|---|---|---|---|---|---|
| Jan | 745 | 236 | 540 | 642.5 | 2 |
| Feb | 847 | 236 | 542 | 793.1 | 1 |
| Mar | 1152 | 440 | 846 | 1134.4 | 0 |
| Apr | 1660 | 847 | 1254 | 1335.2 | 0 |
| May | 2068 | 1355 | 1762 | 1546.1 | 0 |
| Jun | 2374 | 1763 | 2069 | 2529.9 | 0 |
| Jul | 2780 | 2271 | 2476 | 29211 | 0 |
| Aug | 2883 | 2373 | 2578 | 1556.1 | 0 |
| Sep | 2577 | 1967 | 2272 | 1857.3 | 0 |
| Oct | 2068 | 1458 | 1763 | 1144.5 | 0 |
| Nov | 1559 | 1049 | 1254 | 783.1 | 0 |
| Dec | 949 | 440 | 744 | 773.0 | 0 |
| Year | 2883 | 236 | 1558 | 1,69667 | 3 |
“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 | 77% | 86% | 1.9 | 10:07 |
| Feb | 76% | 81% | 2.7 | 10:55 |
| Mar | 76% | 75% | 3.8 | 11:53 |
| Apr | 77% | 69% | 4.8 | 12:00 |
| May | 79% | 68% | 5.3 | 13:55 |
| Jun | 84% | 80% | 4.7 | 14:25 |
| Jul | 85% | 76% | 4.7 | 14:13 |
| Aug | 83% | 68% | 5.0 | 13:25 |
| Sep | 82% | 73% | 4.0 | 12:20 |
| Oct | 78% | 68% | 3.4 | 11:16 |
| Nov | 77% | 74% | 2.4 | 10:20 |
| Dec | 77% | 83% | 1.8 | 9:53 |
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 Shunan is like
The warmest month is August, with an average high of 28 °C83 °F and a low of 23 °C73 °F. The coldest is January, when highs average 7 °C45 °F and lows 2 °C36 °F. Seasons are strongly marked: the warmest month is on average 20.9 °C37.5 °F warmer than the coldest.
It is wet, with about 1,696 mm67 in of precipitation per year. The wettest three-month stretch is June–August, which brings 41% of the annual total. The wettest month is July (292 mm11 in), the driest is January (64 mm2.5 in).
Relative humidity ranges from 76% in March to 85% in July. The clearest skies (lowest average cloud amount, 68%) are typical of August. Average wind speed near the ground ranges from 5 km/h (3 mph) in July to 11 km/h (7 mph) in January. Daylight lasts from about 9.9 hours in December to 14.4 hours in June.
Best time to visit Shunan
Based on these averages, the most comfortable months for sightseeing and outdoor activities are October: average highs of 20 °C68 °F to 20 °C68 °F with 114 mm4.5 in to 114 mm4.5 in of precipitation per month.
The most challenging month is July, which is very wet (292 mm11 in) and humid (85% relative humidity).
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 Shunan
- Winter (December–February) — highs 745 to 9 °C49 °F, lows 236 to 4 °C40 °F, about 74 mm2.9 in of precipitation a month. Pack a warm coat, layers and closed shoes.
- Spring (March–May) — highs 1152 to 20 °C68 °F, lows 440 to 13 °C55 °F, about 133 mm5.2 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 2374 to 28 °C83 °F, lows 1763 to 23 °C73 °F, about 233 mm9.2 in of precipitation a month. Pack light summer clothes such as T-shirts, shorts or light dresses and a good rain jacket or umbrella and quick-drying shoes.
- Autumn (September–November) — highs 1559 to 25 °C77 °F, lows 1049 to 19 °C67 °F, about 126 mm4.9 in of precipitation a month. Pack light layers — T-shirts plus a light sweater or jacket and an umbrella or light rain jacket.
How Shunan compares
Compared with Yamaguchi, about 35 km to the west, Shunan is on average 0.7 °C1.3 °F cooler and receives 7% less precipitation (1,696 mm67 in vs 1,821 mm72 in). The difference is largest in July (1.3 °C2.4 °F cooler).
Of the 111 places in Japan covered by World Climates, Shunan is the 68th warmest by annual mean temperature and the 54th wettest by annual precipitation. See all of them on the Japan climate page.
Places in other countries with the most similar temperature and rainfall pattern: Ulsan (South Korea, Cfa), Geoje (South Korea, Cwa) and Busan (South Korea, Cwa).
The same NASA POWER grid cell also contains Hōfu (pop. 116,925) and Tokuyama (pop. 101,133). Their long-term averages in this dataset are essentially the same as for Shunan, so they do not have separate pages.
Nearby places
- Yamaguchi 35 km · 15 °C60 °F · 1,821 mm72 in
- Ube 55 km · 16 °C61 °F · 1,821 mm72 in
- Hiroshima 67 km · 15 °C60 °F · 1,556 mm61 in
- Kure 70 km · 16 °C61 °F · 1,621 mm64 in
- Matsuyama 91 km · 17 °C62 °F · 1,621 mm64 in
- Kitakyushu 93 km · 17 °C62 °F · 1,860 mm73 in
- Beppu 94 km · 17 °C63 °F · 1,939 mm76 in
- Ōita 96 km · 18 °C64 °F · 2,027 mm80 in
Frequently asked questions
What is the warmest month in Shunan?
August is the warmest month in Shunan, with an average high of 28 °C (83 °F) and an average low of 23 °C (73 °F).
What is the coldest month in Shunan?
January is the coldest month, with an average high of 7 °C (45 °F) and an average low of 2 °C (36 °F).
When does it rain the most in Shunan?
July is the wettest month with about 292 mm (11.5 in) of precipitation; January is the driest with about 64 mm (2.5 in).
What is the best time to visit Shunan?
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 128 m, while Shunan lies at about 316 m. Temperatures on this page were therefore adjusted by −1.2 °C2.2 °F using the standard lapse rate of 6.5 °C per 1,000 m.