nomadseason

Monthly climate in Aso, Japan

Last updated: July 31, 2025

Under the Köppen–Geiger climate classification Aso features a humid subtropical climate (Cfa). Temperatures typically range between 4 °C (39 °F) and 26 °C (79 °F) through the year, but rarely can drop to -8 °C (18 °F) or can rise to as high as 35 °C (96 °F). The average annual precipitation amounts to about 2062 mm (81.2 inches) and receives 143 rainy days on the 1 mm (0.04 inches) threshold annually. Aso enjoys an average of 2984 hours of sunshine throughout the year, and daylight varies from 10 hours 0 minutes to 14 hours 16 minutes per day.

Monthly average temperatures in Aso, Japan

The warmest months in Aso are July, August and September, with daily mean temperatures ranging from 23 to 26 °C (73 - 79 °F) throughout the day. The coldest temperatures usually occur in January, February and December, when daily mean temperatures range from 4 to 5 °C (39 - 41 °F) throughout the day. On average each year, Aso experiences 95 days above 25 °C (77.0 °F) and 56 days below 0 °C (32.0 °F).

Monthly average temperatures with daily means, minimums and maximums for period, average high and low temperatures in Aso. Generated using Copernicus Climate Change Service information. Data for period from January 2017 to June 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Maximum16°C
(62°F)		19°C
(67°F)		23°C
(73°F)		27°C
(81°F)		30°C
(85°F)		31°C
(88°F)		34°C
(94°F)		35°C
(96°F)		33°C
(92°F)		30°C
(87°F)		24°C
(76°F)		21°C
(70°F)
Mean maximum14°C
(58°F)		16°C
(61°F)		21°C
(69°F)		25°C
(78°F)		28°C
(83°F)		29°C
(85°F)		33°C
(91°F)		34°C
(93°F)		31°C
(89°F)		28°C
(82°F)		22°C
(72°F)		17°C
(63°F)
Average high8°C
(47°F)		10°C
(50°F)		15°C
(58°F)		19°C
(66°F)		23°C
(74°F)		26°C
(78°F)		28°C
(83°F)		30°C
(87°F)		27°C
(80°F)		22°C
(72°F)		16°C
(62°F)		10°C
(50°F)
Daily mean4°C
(39°F)		5°C
(41°F)		9°C
(49°F)		14°C
(57°F)		18°C
(65°F)		21°C
(71°F)		25°C
(77°F)		26°C
(79°F)		23°C
(73°F)		17°C
(63°F)		11°C
(51°F)		5°C
(41°F)
Average low-0°C
(32°F)		0°C
(33°F)		4°C
(40°F)		8°C
(47°F)		13°C
(56°F)		17°C
(64°F)		22°C
(72°F)		22°C
(73°F)		19°C
(66°F)		13°C
(55°F)		5°C
(42°F)		0°C
(33°F)
Mean minimum-6°C
(22°F)		-5°C
(24°F)		-2°C
(29°F)		0°C
(33°F)		6°C
(42°F)		13°C
(56°F)		18°C
(65°F)		19°C
(66°F)		13°C
(55°F)		5°C
(42°F)		-2°C
(29°F)		-4°C
(25°F)
Minimum-7°C
(20°F)		-8°C
(18°F)		-3°C
(27°F)		-1°C
(31°F)		2°C
(36°F)		11°C
(52°F)		15°C
(59°F)		16°C
(62°F)		9°C
(49°F)		4°C
(40°F)		-4°C
(25°F)		-5°C
(24°F)

Compare climate in Aso with other places

Compare temperature, precipitation, sunshine, UV index in Aso, Japan with other places around the world.

Monthly average precipitation in Aso, Japan

Aso usually has the most precipitation in June, July and August, with an average of 17 rainy days and 327 mm (12.9 inches) of precipitation per month. The driest months in Aso are January, November and December. On average, 63 mm (2.5 inches) of precipitation falls during these months.

Monthly average precipitation and precipitation days in Aso. Generated using Copernicus Climate Change Service information. Data for period from January 2017 to January 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Average precipitation mm (inches)58 (2.3)98 (3.9)137 (5.4)135 (5.3)209 (8.2)276 (10.9)452 (17.8)253 (10.0)192 (7.6)122 (4.8)60 (2.3)70 (2.8)
Average precipitation days (≥ 1 mm)61012101316211615987

Monthly sunshine hours in Aso, Japan

The sunniest months in Aso are April, May and August, when the sun shines an average of 9 hours 16 minutes a day. Least sunny months in Aso: January, November and December receive an average of 6 hours 49 minutes of sunshine daily.

Mean monthly sunshine duration, average sunshine hours per day and mean daily daylight hours in Aso. Generated using Copernicus Atmosphere Monitoring Service information. Data for period from January 2017 to January 2022.
 JanFebMarAprMayJunJulAugSepOctNovDec
Mean monthly sunshine hours177232259276283253262293248247231218
Mean daily daylight hours10h 13m10h 59m11h 58m12h 59m13h 50m14h 16m14h 3m13h 18m12h 21m11h 20m10h 27m10h 0m

Solar UV radiation in Aso, Japan

Aso experiences the highest level of ultraviolet (UV) radiation in April, July and August, when the maximum UV index can reach values of 11 - 12, which corresponds to the Extreme category of sun exposure. January, February and December are in the Moderate / High exposure category. In these months, the maximum values of the UV index do not exceed 6. For more detailed information, check out our hourly Aso UV Index data.

Average daily maximum UV levels by month for Aso. Generated using Copernicus Atmosphere Monitoring Service information. Data for period from January 2022 to January 2023.
 JanFebMarAprMayJunJulAugSepOctNovDec
UV Index (month maximum)468111111121211864