Jōetsu weather in July
In July, Jōetsu has daytime highs averaging 28 °C, nights around 21 °C, with 20 wet days, and a sea temperature of 23 °C. Figures are 1991–2020 climate normals.
- 27.7°C Average high
- 21.3°C Average low
- 20days Wet days
- 240mm Rainfall
- 23.4°C Sea temperature
- 14h Daylight
Daily temperatures through July
How July develops
Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.
| Days | Avg high | Avg low | Chance of rain |
|---|---|---|---|
| 1–10 July | 26.5 °C | 20.2 °C | 69 % |
| 11–20 July | 27.3 °C | 21.1 °C | 70 % |
| 21–31 July | 29.1 °C | 22.3 °C | 60 % |
- Average highs rise from 26.5 °C early in July to 29.1 °C by the end of it.
- Rain is most likely over days 11–20 of July (70 % of days) and least likely over days 21–31 (60 %).
What to expect
| Measure | Typical July | Share of the month |
|---|---|---|
| Days above 25 °C | 26 of 31 | 82 % |
| Days above 30 °C | 7.0 of 31 | 22 % |
| Days below 0 °C | 0 of 31 | 0 % |
| Days with more than 1 mm rain | 20 of 31 | 66 % |
Conditions in July
| Measure | Average |
|---|---|
| Mean temperature | 24 °C |
| Record high (1991–2020) | 36 °C |
| Record low (1991–2020) | 14 °C |
| Relative humidity | 87 % |
| Wind speed | 9.9 km/h |
| Cloud cover | 77 % |
July compared with the months around it
| Month | Avg high | Rainfall | Cloud |
|---|---|---|---|
| May | 21.0 °C | 126 mm | 66 % |
| June | 24.3 °C | 164 mm | 78 % |
| July | 27.7 °C | 240 mm | 77 % |
| August | 29.2 °C | 196 mm | 67 % |
| September | 25.2 °C | 207 mm | 72 % |
See all twelve months for Jōetsu
- July is the 2nd warmest month here.
- It is the 10th driest month of the year.
- It ranks 11th for least cloud cover.
- Days last about 14 hours from sunrise to sunset.
- It rains on 20 of 31 days — 66 % of the month.
- Nights are about 6.5 °C cooler than the middle of the day.
- The hottest July day on record since 1991 reached 36 °C, 8.0 °C above the usual daytime high.
- Beach score: 73 / 100 — see how this is calculated.
QuestionsJuly in Jōetsu, answered
How warm is Jōetsu in July?
Daily highs average 28 °C and nights fall to about 21 °C, a spread of 6.5 °C between afternoon and dawn. That makes July the 2nd warmest month of the year here.
Does it rain much in Jōetsu in July?
July averages 240 mm of rain, spread over about 20 of the 31 days — 66 % of the month. Cloud cover averages 77 % of the sky.
Is the sea warm enough to swim in July?
The sea averages 23 °C off Jōetsu in July. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.
How long are the days in July?
Jōetsu averages 14 hours between sunrise and sunset in July. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.
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
- Dataset version
- era5-1991-2020-scores1.1
- Last processed
Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. 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.