Climate averages 1991–2020
Ōmihachiman weather
in December.
A cool, moderately wet month: the 10th warmest and the driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cool month in Ōmihachiman: daytime highs average 9.6°C and nights cool to about 2.4°C. By daytime temperature it is the 10th warmest of the 12 months.
Expect about 75 mm of rain on roughly 12 days, which makes December a moderately wet month (the driest month of the year). Daylight, from sunrise to sunset, lasts about 9 h 50 min on an average December day.
The nearest other city in this atlas is Youkaichi (9 km away). In December its highs average 9.6°C, about as warm as Ōmihachiman, with 60 mm of rain.
Among the 303 cities listed in Japan, Ōmihachiman ranks joint 215th of 303 for the warmest December highs and joint 204th of 303 for the driest December (rainfall, lowest first). The mean December high of those 303 cities is 9.5°C; Ōmihachiman is 0.2°C warmer than that mean.
From December to January, average highs fall by 2.5°C to 7.1°C, and monthly rainfall rises from 75 mm to 81 mm.
The annual picture
December in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Ōmihachiman climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 7.1°C0.0°C | 0.0°C | 81 | 13.9 | 10.110 h |
| February | 8.0°C0.0°C | 0.0°C | 78 | 13.0 | 10.911 h |
| March | 11.8°C2.6°C | 2.6°C | 116 | 13.5 | 11.912 h |
| April | 17.2°C7.4°C | 7.4°C | 123 | 11.6 | 13.113 h |
| May | 21.9°C12.6°C | 12.6°C | 148 | 11.6 | 14.014 h |
| June | 25.3°C17.3°C | 17.3°C | 186 | 14.0 | 14.514 h |
| July | 28.9°C21.8°C | 21.8°C | 210 | 15.9 | 14.314 h |
| August | 30.2°C22.8°C | 22.8°C | 122 | 12.3 | 13.513 h |
| September | 26.2°C19.1°C | 19.1°C | 179 | 12.3 | 12.412 h |
| October | 20.5°C13.2°C | 13.2°C | 152 | 10.8 | 11.311 h |
| November | 15.1°C7.5°C | 7.5°C | 81 | 9.0 | 10.410 h |
| December, selected | 9.6°C2.4°C | 2.4°C | 75 | 11.6 | 9.810 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
December in nearby cities
- Youkaichi in DecemberJapan · 9 kmHigh 9.6°C · Low 2.3°C · 60 mm rain
- Moriyama in DecemberJapan · 12 kmHigh 9.7°C · Low 2.4°C · 58 mm rain
- Kusatsu in DecemberJapan · 17 kmHigh 9.7°C · Low 2.1°C · 58 mm rain
- Kōka in DecemberJapan · 17 kmHigh 9.5°C · Low 1.9°C · 60 mm rain
- Hikone in DecemberJapan · 19 kmHigh 9.3°C · Low 3.3°C · 72 mm rain
- Ōtsu in DecemberJapan · 25 kmHigh 9.5°C · Low 1.8°C · 65 mm rain
- Nagahama in DecemberJapan · 32 kmHigh 9.1°C · Low 2.9°C · 111 mm rain
- Kyoto in DecemberJapan · 33 kmHigh 10.0°C · Low 2.3°C · 65 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Ōmihachiman) is explained once on the Ōmihachiman year overview and on the Sources, method and limits page.