Climate averages 1991–2020
Inzai 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 Inzai: daytime highs average 10.6°C and nights cool to about 3.0°C. By daytime temperature it is the 10th warmest of the 12 months.
Expect about 68 mm of rain on roughly 8 days, which makes December a moderately wet month (the driest month of the year). Daylight, from sunrise to sunset, lasts about 9 h 47 min on an average December day.
The nearest other city in this atlas is Ryūgasaki (7 km away). In December its highs average 10.7°C, about as warm as Inzai, with 61 mm of rain.
Among the 303 cities listed in Japan, Inzai ranks joint 112th of 303 for the warmest December highs and joint 145th of 303 for the driest December (rainfall, lowest first). The mean December high of those 303 cities is 9.5°C; Inzai is 1.1°C warmer than that mean.
From December to January, average highs fall by 2.4°C to 8.2°C, and monthly rainfall rises from 68 mm to 74 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
Inzai climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 8.2°C0.2°C | 0.2°C | 74 | 7.5 | 10.010 h |
| February | 9.2°C0.7°C | 0.7°C | 72 | 8.6 | 10.911 h |
| March | 12.6°C4.0°C | 4.0°C | 125 | 12.8 | 11.912 h |
| April | 17.5°C8.9°C | 8.9°C | 113 | 12.5 | 13.113 h |
| May | 22.0°C14.0°C | 14.0°C | 128 | 11.6 | 14.014 h |
| June | 24.8°C17.9°C | 17.9°C | 159 | 13.7 | 14.515 h |
| July | 28.6°C21.9°C | 21.9°C | 150 | 13.8 | 14.314 h |
| August | 30.0°C23.3°C | 23.3°C | 114 | 11.9 | 13.514 h |
| September | 26.2°C20.2°C | 20.2°C | 175 | 14.3 | 12.412 h |
| October | 20.8°C14.6°C | 14.6°C | 207 | 13.0 | 11.311 h |
| November | 15.7°C8.7°C | 8.7°C | 102 | 10.4 | 10.310 h |
| December, selected | 10.6°C3.0°C | 3.0°C | 68 | 8.4 | 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
- Ryūgasaki in DecemberJapan · 7 kmHigh 10.7°C · Low 2.3°C · 61 mm rain
- Toride in DecemberJapan · 10 kmHigh 10.7°C · Low 2.2°C · 56 mm rain
- Yachiyo in DecemberJapan · 12 kmHigh 10.7°C · Low 3.8°C · 63 mm rain
- Sakura in DecemberJapan · 15 kmHigh 10.8°C · Low 4.1°C · 68 mm rain
- Ushiku in DecemberJapan · 15 kmHigh 10.4°C · Low 1.9°C · 61 mm rain
- Narita in DecemberJapan · 15 kmHigh 10.7°C · Low 3.0°C · 68 mm rain
- Kamagaya in DecemberJapan · 16 kmHigh 10.6°C · Low 2.7°C · 63 mm rain
- Kashiwa in DecemberJapan · 17 kmHigh 10.5°C · Low 2.0°C · 63 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 Inzai) is explained once on the Inzai year overview and on the Sources, method and limits page.
Sakura and Narita lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.