Climate averages 1991–2020
Karatsu weather
in December.
A cool, moderately wet month: the 10th warmest and the 3rd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
December is a cool month in Karatsu: daytime highs average 11.4°C and nights cool to about 6.7°C. By daytime temperature it is the 10th warmest of the 12 months.
Expect about 81 mm of rain on roughly 11 days, which makes December a moderately wet month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 9 h 59 min on an average December day.
The nearest other city in this atlas is Itoshima (23 km away). In December its highs average 10.8°C, 0.6°C cooler than Karatsu, with 72 mm of rain.
Among the 303 cities listed in Japan, Karatsu ranks joint 39th of 303 for the warmest December highs and joint 220th of 303 for the driest December (rainfall, lowest first). The mean December high of those 303 cities is 9.5°C; Karatsu is 1.9°C warmer than that mean.
From December to January, average highs fall by 2.4°C to 9.0°C, and monthly rainfall falls from 81 mm to 76 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
Karatsu climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 9.0°C4.5°C | 4.5°C | 76 | 11.9 | 10.210 h |
| February | 10.2°C4.6°C | 4.6°C | 80 | 10.5 | 11.011 h |
| March | 13.6°C7.1°C | 7.1°C | 124 | 11.6 | 12.012 h |
| April | 18.4°C11.0°C | 11.0°C | 134 | 11.0 | 13.013 h |
| May | 22.7°C15.6°C | 15.6°C | 143 | 10.3 | 13.914 h |
| June | 25.6°C19.8°C | 19.8°C | 277 | 14.7 | 14.314 h |
| July | 29.1°C24.1°C | 24.1°C | 260 | 15.3 | 14.114 h |
| August | 30.4°C25.1°C | 25.1°C | 162 | 13.7 | 13.413 h |
| September | 27.0°C21.8°C | 21.8°C | 179 | 12.6 | 12.412 h |
| October | 22.1°C16.7°C | 16.7°C | 103 | 8.1 | 11.411 h |
| November | 16.8°C11.5°C | 11.5°C | 94 | 9.3 | 10.510 h |
| December, selected | 11.4°C6.7°C | 6.7°C | 81 | 11.1 | 10.010 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
- Itoshima in DecemberJapan · 23 kmHigh 10.8°C · Low 6.3°C · 72 mm rain
- Maebaru-chūō in DecemberJapan · 25 kmHigh 11.2°C · Low 7.1°C · 72 mm rain
- Sasebo in DecemberJapan · 38 kmHigh 11.7°C · Low 7.3°C · 69 mm rain
- Saga in DecemberJapan · 39 kmHigh 11.3°C · Low 5.0°C · 71 mm rain
- Fukuoka in DecemberJapan · 45 kmHigh 11.1°C · Low 5.3°C · 69 mm rain
- Kasuga in DecemberJapan · 47 kmHigh 10.9°C · Low 3.9°C · 69 mm rain
- Tosu in DecemberJapan · 51 kmHigh 11.1°C · Low 3.4°C · 70 mm rain
- Kurume in DecemberJapan · 53 kmHigh 11.2°C · Low 3.5°C · 70 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 Karatsu) is explained once on the Karatsu year overview and on the Sources, method and limits page.