Climate of Gunma Prefecture, Japan
Area-weighted average across Gunma Prefecture. For where people actually live and travel, see the cities below.
Gunma Prefecture, a subdivision of Japan, has a seasonal climate on average. Area-weighted monthly temperatures across the whole territory range from -1.3°C / 29.7°F in January to 22.5°C / 72.5°F in August, with rainfall from 52 mm / 2 in to 212 mm / 8.3 in depending on the season (1478 mm / 58.2 in total across the year). See the city listed below for point-value climate at specific locations — these often differ from the area-weighted average, especially in geographically diverse subdivisions.
| Month | Temperature | Rainfall | Matches |
|---|---|---|---|
| January | -1.3°C29.7°F | 63 mm2.5″ | Snowy |
| February | -1.1°C30°F | 70 mm2.8″ | Snowy |
| March | 1.9°C35.4°F | 79 mm3.1″ | Snowy |
| April | 8.4°C47.1°F | 100 mm3.9″ | — |
| May | 13.4°C56.1°F | 117 mm4.6″ | — |
| June | 17.3°C63.1°F | 180 mm7.1″ | — |
| July | 21.2°C70.2°F | 189 mm7.4″ | — |
| August | 22.5°C72.5°F | 209 mm8.2″ | — |
| September | 18.2°C64.8°F | 212 mm8.3″ | — |
| October | 12.1°C53.8°F | 133 mm5.2″ | — |
| November | 6.7°C44.1°F | 74 mm2.9″ | — |
| December | 1.6°C34.9°F | 52 mm2″ | Snowy |
Frequently asked questions
What is the best time to visit Gunma Prefecture?
Gunma Prefecture, Japan does not have a clear sunny-and-dry window by our cutoffs. The warmest month is August at 22.5°C / 72.5°F, and the driest is December at 52 mm / 2 in — likely your best travel window. For city-level detail, see the cities section below.
What is the climate of Gunma Prefecture?
Gunma Prefecture, Japan has area-weighted monthly average temperatures ranging from -1.3°C / 29.7°F in January to 22.5°C / 72.5°F in August. Annual rainfall averages about 1478 mm / 58.2 in, with the wettest month being September (212 mm / 8.3 in) and the driest December (52 mm / 2 in). Because this is an area average across the whole subdivision, local city values can differ substantially.
What is the hottest month in Gunma Prefecture?
The hottest month in Gunma Prefecture is August, with an area-wide average temperature of 22.5°C / 72.5°F.
What is the coldest month in Gunma Prefecture?
The coldest month in Gunma Prefecture is January, with an area-wide average temperature of -1.3°C / 29.7°F.
When does it rain most in Gunma Prefecture?
The wettest month in Gunma Prefecture is September, averaging about 212 mm / 8.3 in of rainfall. The driest is December with about 52 mm / 2 in.