Climate averages 1991–2020
Niihama weather
in July.
A hot, very wet month: the 2nd warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
July is a hot month in Niihama: daytime highs average 29.5°C and nights cool to about 23.9°C. By daytime temperature it is the 2nd warmest of the 12 months.
Expect about 228 mm of rain on roughly 16 days, which makes July a very wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 11 min on an average July day.
The nearest other city in this atlas is Saijō (12 km away). In July its highs average 30.5°C, 0.9°C warmer than Niihama, with 228 mm of rain.
Among the 303 cities listed in Japan, Niihama ranks joint 24th of 303 for the warmest July highs and joint 201st of 303 for the driest July (rainfall, lowest first). The mean July high of those 303 cities is 27.9°C; Niihama is 1.6°C warmer than that mean.
From July to August, average highs rise by 1.1°C to 30.6°C, and monthly rainfall falls from 228 mm to 151 mm.
The annual picture
July 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
Niihama climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 9.0°C3.3°C | 3.3°C | 78 | 13.5 | 10.210 h |
| February | 10.1°C3.3°C | 3.3°C | 86 | 12.3 | 10.911 h |
| March | 13.6°C5.8°C | 5.8°C | 122 | 13.4 | 12.012 h |
| April | 18.5°C10.4°C | 10.4°C | 134 | 11.6 | 13.013 h |
| May | 22.8°C15.1°C | 15.1°C | 158 | 11.2 | 13.914 h |
| June | 25.8°C19.5°C | 19.5°C | 249 | 15.1 | 14.414 h |
| July, selected | 29.5°C23.9°C | 23.9°C | 228 | 15.6 | 14.214 h |
| August | 30.6°C24.8°C | 24.8°C | 151 | 13.8 | 13.413 h |
| September | 27.1°C21.4°C | 21.4°C | 216 | 14.1 | 12.412 h |
| October | 21.9°C15.7°C | 15.7°C | 166 | 11.0 | 11.411 h |
| November | 16.6°C10.2°C | 10.2°C | 90 | 9.9 | 10.410 h |
| December | 11.4°C5.5°C | 5.5°C | 90 | 12.8 | 9.910 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
July in nearby cities
- Saijō in JulyJapan · 12 kmHigh 30.5°C · Low 24.4°C · 228 mm rain
- Shikokuchūō in JulyJapan · 23 kmHigh 29.7°C · Low 23.7°C · 265 mm rain
- Imabari in JulyJapan · 31 kmHigh 28.5°C · Low 24.0°C · 225 mm rain
- Shinagawa in JulyJapan · 45 kmHigh 29.1°C · Low 22.7°C · 279 mm rain
- Kochi in JulyJapan · 50 kmHigh 28.9°C · Low 22.9°C · 374 mm rain
- Matsuyama in JulyJapan · 52 kmHigh 29.7°C · Low 24.0°C · 239 mm rain
- Onomichi in JulyJapan · 52 kmHigh 28.8°C · Low 22.8°C · 189 mm rain
- Mihara in JulyJapan · 53 kmHigh 29.3°C · Low 23.1°C · 207 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 Niihama) is explained once on the Niihama year overview and on the Sources, method and limits page.
Saijō lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.