Ōtsu climate
Ōtsu is warmest in August, with average highs of 31 °C, and coldest in January, when nights average -0.3 °C. July is the wettest month (236 mm) and January the driest (65 mm). Figures are 1991–2020 climate normals.
Across a full year Ōtsu averages 1,641 mm of rain, 104 days above 25 °C and 48 days below freezing.
Japan · population 345,070 · 1991–2020 normals
Temperature below 0 °C to above 30 °C Rain band height is that month’s share of the wettest month
- Warmest month August 31 °C
- Coldest month January -0.3 °C
- Driest month January 65 mm
- Wettest month July 236 mm
- Least cloud December 51 % cloud
- Hottest on record August 38 °C
- Coldest on record January -8.1 °C
What to expectŌtsu through the year
Ōtsu has a clear annual cycle: average daily highs run from 7.0 °C in January to 31 °C in August, a swing of 23 °C in mean temperature across the year.
Counted across a normal year, 104 days a year reach 25 °C, 37 of them reach 30 °C, 48 nights drop below freezing. The warmest reading in the 1991–2020 record is 38 °C, in August.
Rain is strongly seasonal. July averages 236 mm against 65 mm in January — 3.6 times as much. Planning around the dry months matters more here than planning around temperature.
Month by month
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| January | 7.0 °C | 65 mm | 56 % |
| February | 8.0 °C | 74 mm | 59 % |
| March | 11.8 °C | 121 mm | 61 % |
| April | 17.3 °C | 134 mm | 62 % |
| May | 22.1 °C | 155 mm | 67 % |
| June | 25.5 °C | 215 mm | 80 % |
| July | 29.0 °C | 236 mm | 74 % |
| August | 30.6 °C | 139 mm | 62 % |
| September | 26.4 °C | 191 mm | 64 % |
| October | 20.6 °C | 164 mm | 55 % |
| November | 15.1 °C | 82 mm | 52 % |
| December | 9.5 °C | 66 mm | 51 % |
Temperature month by month
| Month | Avg high | Avg low | Mean | Record high | Record low | Days above 25 °C | Days above 30 °C | Days below 0 °C |
|---|---|---|---|---|---|---|---|---|
| January | 7.0 °C | -0.3 °C | 2.9 °C | 15.9 °C | -8.1 °C | 0 | 0 | 18 |
| February | 8.0 °C | 0.1 °C | 3.6 °C | 19.8 °C | -7.6 °C | 0 | 0 | 16 |
| March | 11.8 °C | 3.0 °C | 7.0 °C | 21.6 °C | -4.8 °C | 0 | 0 | 6 |
| April | 17.3 °C | 8.0 °C | 12.3 °C | 27.0 °C | -1.3 °C | 0 | 0 | 0 |
| May | 22.1 °C | 13.1 °C | 17.2 °C | 30.4 °C | 3.9 °C | 6 | 0 | 0 |
| June | 25.5 °C | 17.7 °C | 21.2 °C | 33.4 °C | 10.5 °C | 17 | 1 | 0 |
| July | 29.0 °C | 21.9 °C | 25.1 °C | 35.9 °C | 14.8 °C | 29 | 13 | 0 |
| August | 30.6 °C | 22.8 °C | 26.2 °C | 38.1 °C | 16.5 °C | 30 | 19 | 0 |
| September | 26.4 °C | 19.1 °C | 22.3 °C | 35.0 °C | 9.4 °C | 20 | 3 | 0 |
| October | 20.6 °C | 13.0 °C | 16.4 °C | 29.4 °C | 3.7 °C | 2 | 0 | 0 |
| November | 15.1 °C | 7.2 °C | 10.7 °C | 25.3 °C | -0.8 °C | 0 | 0 | 0 |
| December | 9.5 °C | 1.9 °C | 5.3 °C | 21.8 °C | -7.6 °C | 0 | 0 | 8 |
Rain, sun and wind month by month
| Month | Rainfall | Wet days | Daylight | Cloud cover | Humidity | Wind |
|---|---|---|---|---|---|---|
| January | 65 mm | 8 | 10 h/day | 56 % | 76 % | 16 km/h |
| February | 74 mm | 9 | 11 h/day | 59 % | 75 % | 16 km/h |
| March | 121 mm | 12 | 12 h/day | 61 % | 74 % | 17 km/h |
| April | 134 mm | 12 | 13 h/day | 62 % | 73 % | 16 km/h |
| May | 155 mm | 11 | 14 h/day | 67 % | 76 % | 15 km/h |
| June | 215 mm | 15 | 15 h/day | 80 % | 80 % | 14 km/h |
| July | 236 mm | 17 | 14 h/day | 74 % | 83 % | 13 km/h |
| August | 139 mm | 13 | 13 h/day | 62 % | 79 % | 13 km/h |
| September | 191 mm | 13 | 12 h/day | 64 % | 81 % | 14 km/h |
| October | 164 mm | 10 | 11 h/day | 55 % | 80 % | 14 km/h |
| November | 82 mm | 8 | 10 h/day | 52 % | 79 % | 14 km/h |
| December | 66 mm | 8 | 9.8 h/day | 51 % | 78 % | 15 km/h |
Planning a trip? See the best time to visit Ōtsu.
QuestionsCommon questions about Ōtsu’s climate
When is the best time to visit Ōtsu?
That depends on what you want, so the honest answer is a comparison rather than a single month. May, June, September sit closest to 20 °C on average, August is the warmest month and January the driest. The month-by-month table above has the full picture.
How hot does Ōtsu get?
In August, the warmest month, daily highs average 31 °C. About 37 days a year pass 30 °C. The highest value in the 1991–2020 record is 38 °C.
How cold does it get in winter?
Nights average -0.3 °C in January, the coldest month. A normal year has 48 nights below freezing.
Which month is wettest in Ōtsu?
July, averaging 236 mm over 17 days with rain. The driest month is January with 65 mm. The year as a whole averages 1,641 mm.
Are these figures a forecast?
No. They are 1991–2020 climate normals: the average of thirty years, which describes what a month is usually like in Ōtsu rather than what any particular week will bring. Individual years can differ substantially from the normal.
Data sources and method
- ERA5 / ERA5-Land reanalysis — Copernicus Climate Change Service (C3S), ECMWF. Copernicus Licence
- Open-Meteo — Open-Meteo.com. CC BY 4.0
- NOAA OISST v2.1 — NOAA Physical Sciences Laboratory. Public domain
- GeoNames — GeoNames.org. CC BY 4.0
- Normal period
- 1991–2020
- Data point
- 35.000°, 135.867° (the coordinates the reanalysis values are taken for)
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: monthly rankings, daylight hours, beach and comfort scores. Full formulas are on the methodology page.
Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.